This application claims the benefit of priority to U.S. Patent Application Serial
No. 13/725,421 entitled "HOLLOW HYDROGEL CAPSULES AND METHODS OF USING
THE SAME," filed December 21, 2012, the disclosure of which is incorporated herein in its
entirety by reference.
BACKGROUND OF THE INVENTION
[0002] During the drilling, completion, and production phases of wells for petroleum or
water extraction, the use of precise chemical compositions downhole is important for a wide
variety of purposes. Current techniques expose all chemical components of a composition for
use downhole to the borehole and other materials downhole en route to a desired location
without the ability to control or modulate the concentration or reactivity of the chemical
component on its way to a target location.
SUMMARY OF THE INVENTION
[0003] In various embodiments, the present invention provides a hollow hydrogel
capsule for treatment of a subterranean formation. The hollow hydrogel capsule includes a
hydrogel shell. The hydrogel shell includes a polymerized composition that is hydrolyzed and
crosslinked. The pre-polymerized composition includes at least one vinyl amine. The vinyl
amine includes at least one hydrolytically deprotectable masked primary amine. The prepolymerized
composition also includes at least one polyvinyl compound. The hydrogel capsule
also includes a hollow interior. The hollow interior includes at least one component of a
composition for use downhole. The downhole composition is for subterranean petroleum or
water well drilling, stimulation, clean-up, production, completion, abandonment, or a
combination thereof. The crosslinking of the hydrolyzed and crosslinked polymerized
composition includes crosslinking with at least one molecule including a plurality of functional
groups condensable with primary amines.
[0004] In various embodiments, the present invention provides a hydrogel capsule
composition for treatment of a subterranean formation. The hydrogel capsule composition
includes at least one of the hollow hydrogel capsules having at least one component of a
composition for use downhole therein. The hydrogel capsule composition also includes a
downhole composition for subterranean petroleum or water well drilling, stimulation, clean-up,
production, completion, abandonment, or a combination thereof.
[0005] In various embodiments, the present invention provides a method of making the
hollow hydrogel capsule having at least one component of a composition for use downhole
therein. The method includes polymerizing the pre-polymerized composition including the at
least one vinyl amine including the hydrolytically deprotectable masked primary amine, and the
at least one polyvinyl compound. The polymerizing gives a first polymer. The method also
includes hydrolyzing the first polymer, to deprotect at least some of the masked primary amine.
The hydrolyzing gives a second polymer. The method also includes cross-linking the second
polymer with the at least one molecule including the plurality of functional groups condensable
with primary amines. The crosslinking give the hydrogel shell including the hydrolyzed and
crosslinked polymerized composition.
[0006] In various embodiments, the present invention provides a method of using a
hydrogel capsule for treatment of a subterranean formation. The method includes obtaining or
providing one or more of the hollow hydrogel capsules having at least one component of a
composition for use downhole therein. The method also includes contacting the hollow hydrogel
capsules with a subterranean material downhole.
[0007] Various embodiments of the present invention provide certain advantages over
other hydrogel capsules, compositions including the same, methods of making the same, and
methods of using the same, at least some of which are unexpected. Various embodiments can
advantageously allow high degrees of control over the rate, time, and location of delivery of
certain cargo within the hollow interior of the capsule. For example, in certain embodiments, the
hydrogel capsules of the present invention can selectively release a cargo over a broad or narrow
area downhole, advantageously allowing targeting delivery of particular cargo. In various
embodiments, the permeability of the hydrogel capsule can be adjusted above ground or
downhole to allow the delivery of a cargo at a desired location or at a desired rate. In some
examples, conditions downhole, such as the chemical environment, temperature conditions,
pressure conditions, or vibration/agitation conditions, can be used to trigger the release of cargo
from the hydrogel capsules. In some embodiments, the chemical composition of the hydrogel
capsule can be adjusted to yield a desired release profile or a desired triggering mechanism. In
some examples, the hydrogel capsules can release cargo at a precise time or location in a
wellbore, such as due to external environmental stimulus such as conditions downhole, due to
time delay, or due to triggering mechanisms that can be controlled from the surface such as laser
light or agitation.
BRIEF DESCRIPTION OF THE FIGURES
[0008] In the drawings, which are not necessarily drawn to scale, like numerals describe
substantially similar components throughout the several views. Like numerals having different
letter suffixes represent different instances of substantially similar components. The drawings
illustrate generally, by way of example, but not by way of limitation, various embodiments
discussed in the present document.
[0009] FIG. l a illustrates a CLSM image of hollow PVAm hydrogel capsules after in situ
hydrolysis and cross-linking, in accordance with various embodiments.
[0010] FIG. l b illustrates a CLSM image of hollow hydrogel capsules prepared after the
stepwise hydrolysis followed by cross-linking, in accordance with various embodiments.
[0011] FIG l c illustrates a SEM image of the hollow hydrogel capsules shown in panel
FIG la, after lyophilization, in accordance with various embodiments.
[0012] FIG Id illustrates a cryo-SEM image of a freeze-fractured hollow hydrogel
capsule prepared from 0.1 mol GA treatment, in accordance with various embodiments.
[0013] FIG. 2a illustrates Particle size and shell thickness as a function of GA
concentration, in accordance with various embodiments.
[0014] FIG. 2b illustrates changes in both particle size and shell thickness plotted against
cross-linking reaction time, in accordance with various embodiments.
[0015] FIGS. 3a-e illustrate CLSM images of hollow hydrogel capsules prepared with
different concentrations of GA, in accordance with various embodiments: (a) 0.1 mol; (b) 0.05
mol; (c) 0.02 mol; (d) 0.015 mol; (e) 0.01 mol.
[0016] FIGS. 4a-f illustrate CLSM images of hollow hydrogel capsules as a function of
crosslinking reaction time, in accordance with various embodiments: (a) 2 h; (b) 4 h; (c) 8 h; (d)
12 h; (e) 16 h; (f) 20 h.
[0017] FIGS. 5a-b illustrate permeation of FITC-labeled dextran through the shell phases
crosslinked with (a) 0.015 mol GA and (b) 0.1 mol GA, in accordance with various
embodiments.
[0018] FIG. 6 illustrates permeation of FITC-labeled dextran through the hydrogel shell
phases cross-linked with GA followed by the posttreatment with HA, with the numbers in the
images denoting the average molecular weight of FITC-labeled dextran, in accordance with
various embodiments.
[0019] FIG. 7a-c illustrate permeability of a low molecular weight anionic dye through a
hydrogel shell phase treated with HA, in accordance with various embodiments: (a) 0.05 mol GA
without HA treatment 5 min after incubation, (b) 0.015 mol GA followed by the treatment with
250 kDa HA, and (c) 0.015 mol GA followed by the treatment with 1.45 MDa HA 60 min after
incubation.
[0020] FIGS. 8a-d illustrate Au NPs synthesized using different concentrations of GA, in
accordance with various embodiments: (a) 0.015 mol; (b) 0.02 mol; (c) 0.05 mol; (d) 0.1 mol.
[0021] FIGS. 9a-f illustrate incorporation of Au NPs within the hydrogel shell phases,
synthesized using different concentrations of HAuCU solution, in accordance with various
embodiments: (a, b) 2 mM; (c, d) 10 mM; (e, f) 50 mM, wherein (b), (d), and (f) show the high
magnification for those of (a), (c), and (e), respectively.
[0022] FIG. 10 illustrates UV-visible spectra of Au NP/PVAm composite capsules
prepared with different GA concentrations, in accordance with various embodiments.
[0023] FIG. 11 illustrates UV-visible spectra of Au NP/poly(vinylamine) composite
capsules prepared with different HAuCU concentrations, in accordance with various
embodiments.
[0024] FIG. 12a illustrate SEM images of Au NP/PVAm composite capsules before
irradiation, in accordance with various embodiments.
[0025] FIG. 12b illustrate SEM images of Au NP/PVAm composite capsules after strong
radiant exposure of 200 mJ/cm , in accordance with various embodiments.
[0026] FIG. 13a illustrates SEM images of Au NP/PVAm composite capsules after weak
radiant exposure (50 mJ/cm ), in accordance with various embodiments.
[0027] FIG. 13b illustrates SEM images of Au NP/PVAm composite capsules after
moderate radiant exposure (100 mJ/cm ), in accordance with various embodiments.
[0028] FIGS. 14a-d illustrate SEM images of Au NP/PVAm composite capsules prepared
from 0.02 mol GA treated capsules and different concentrations of gold precursors after
irradiation, in accordance with various embodiments: (a) no gold precursor; (b) 2 mM HAuCU;
(c) 10 mM HAuCU; (d) 50 mM HAuCL.
DETAILED DESCRIPTION OF THE INVENTION
[0029] Reference will now be made in detail to certain embodiments of the disclosed
subject matter, examples of which are illustrated in part in the accompanying drawings. While
the disclosed subject matter will be described in conjunction with the enumerated claims, it will
be understood that the exemplified subject matter is not intended to limit the claims to the
disclosed subject matter.
[0030] Values expressed in a range format should be interpreted in a flexible manner to
include not only the numerical values explicitly recited as the limits of the range, but also to
include all the individual numerical values or sub-ranges encompassed within that range as if
each numerical value and sub-range is explicitly recited. For example, a range of "about 0.1% to
about 5%" or "about 0.1% to 5%" should be interpreted to include not just about 0.1% to about
5%, but also the individual values (e.g., 1%, 2%, 3%, and 4%) and the sub-ranges (e.g., 0.1% to
0.5%, 1.1% to 2.2%, 3.3% to 4.4%) within the indicated range. The statement "about X to Y"
has the same meaning as "about X to about Y," unless indicated otherwise. Likewise, the
statement "about X, Y, or about Z" has the same meaning as "about X, about Y, or about Z,"
unless indicated otherwise.
[0031] In this document, the terms "a," "an," or "the" are used to include one or more
than one unless the context clearly dictates otherwise. The term "or" is used to refer to a
nonexclusive "or" unless otherwise indicated. In addition, it is to be understood that the
phraseology or terminology employed herein, and not otherwise defined, is for the purpose of
description only and not of limitation. Any use of section headings is intended to aid reading of
the document and is not to be interpreted as limiting; information that is relevant to a section
heading may occur within or outside of that particular section. Furthermore, all publications,
patents, and patent documents referred to in this document are incorporated by reference herein
in their entirety, as though individually incorporated by reference. In the event of inconsistent
usages between this document and those documents so incorporated by reference, the usage in
the incorporated reference should be considered supplementary to that of this document; for
irreconcilable inconsistencies, the usage in this document controls.
[0032] In the methods of manufacturing described herein, the steps can be carried out in
any order without departing from the principles of the invention, except when a temporal or
operational sequence is explicitly recited.
[0033] Furthermore, specified steps can be carried out concurrently unless explicit claim
language recites that they be carried out separately. For example, a claimed step of doing X and
a claimed step of doing Y can be conducted simultaneously within a single operation, and the
resulting process will fall within the literal scope of the claimed process.
Definitions
[0034] The term "about" as used herein can allow for a degree of variability in a value or
range, for example, within 10%, within 5%, or within 1% of a stated value or of a stated limit of
a range.
[0035] The term "substantially" as used herein refers to a majority of, or mostly, as in at
least about 50%, 60%, 70%, 80%, 90%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.9%, 99.99%, or
at least about 99.999% or more.
[0036] The term "organic group" as used herein refers to but is not limited to any carboncontaining
functional group.
[0037] The term "substituted" as used herein refers to an organic group as defined herein
or molecule in which one or more hydrogen atoms contained therein are replaced by one or more
non-hydrogen atoms. The term "functional group" or "substituent" as used herein refers to a
group that can be or is substituted onto a molecule, or onto an organic group. Examples of
substituents or functional groups include, but are not limited to, a halogen (e.g., F, CI, Br, and I);
an oxygen atom in groups such as hydroxyl groups, alkoxy groups, aryloxy groups, aralkyloxy
groups, oxo(carbonyl) groups, carboxyl groups including carboxylic acids, carboxylates, and
carboxylate esters; a sulfur atom in groups such as thiol groups, alkyl and aryl sulfide groups,
sulfoxide groups, sulfone groups, sulfonyl groups, and sulfonamide groups; a nitrogen atom in
groups such as amines, hydroxylamines, nitriles, nitro groups, N-oxides, hydrazides, azides, and
enamines; and other heteroatoms in various other groups. Non-limiting examples of substituents
J that can be bonded to a substituted carbon (or other) atom include F, CI, Br, I, OR',
OC(0)N(R') 2, CN, NO, N0 2, ON0 2, azido, CF3, OCF3, R', O (oxo), S (thiono), C(O), S(O),
methylenedioxy, ethylenedioxy, N(R')2, SR', SOR', S0 2R', S0 2N(R')2, S0 3R', C(0)R',
C(0)C(0)R', C(0)CH 2C(0)R', C(S)R', C(0)OR', OC(0)R', C(0)N(R') 2, OC(0)N(R') 2,
C(S)N(R')2, (CH2)o-2N(R')C(0)R', (CH2)0-2N(R')N(R')2, N(R')N(R')C(0)R', N(R')N(R')C(0)OR',
N(R')N(R')CON(R')2, N(R')S0 2R', N(R')S0 2N(R')2, N(R')C(0)OR', N(R')C(0)R, N(R')C(S)R,
N(R')C(0)N(R') 2, N(R')C(S)N(R') 2, N(COR')COR', N(OR')R, C(=NH)N(R') 2, C(0)N(OR')R', or
C(=NOR')R' wherein R' can be hydrogen or a carbon-based moiety, and wherein the carbonbased
moiety can itself be further substituted; for example, wherein R' can be hydrogen, alkyl,
acyl, cycloalkyl, aryl, aralkyl, heterocyclyl, heteroaryl, or heteroarylalkyl, wherein any alkyl,
acyl, cycloalkyl, aryl, aralkyl, heterocyclyl, heteroaryl, or heteroarylalkyl or R' can be
independently mono- or multi- substituted with J ; or wherein two R' groups bonded to a nitrogen
atom or to adjacent nitrogen atoms can together with the nitrogen atom or atoms form a
heterocyclyl, which can be mono- or independently multi- substituted with J .
[0038] The term "alkyl" as used herein refers to straight chain and branched alkyl groups
and cycloalkyl groups having from 1 to 40 carbon atoms, 1 to about 20 carbon atoms, 1 to 12
carbons or, in some embodiments, from 1 to 8 carbon atoms. Examples of straight chain alkyl
groups include those with from 1 to 8 carbon atoms such as methyl, ethyl, n-propyl, n-butyl, npentyl,
n-hexyl, n-heptyl, and n-octyl groups. Examples of branched alkyl groups include, but
are not limited to, isopropyl, iso-butyl, sec-butyl, t-butyl, neopentyl, isopentyl, and 2,2-
dimethylpropyl groups. As used herein, the term "alkyl" encompasses n-alkyl, isoalkyl, and
anteisoalkyl groups as well as other branched chain forms of alkyl. Representative substituted
alkyl groups can be substituted one or more times with any of the groups listed herein, for
example, amino, hydroxy, cyano, carboxy, nitro, thio, alkoxy, and halogen groups.
[0039] The term "alkenyl" as used herein refers to straight and branched chain and cyclic
alkyl groups as defined herein, except that at least one double bond exists between two carbon
atoms. Thus, alkenyl groups have from 2 to 40 carbon atoms, or 2 to about 20 carbon atoms, or
2 to 12 carbons or, in some embodiments, from 2 to 8 carbon atoms. Examples include, but are
not limited to
vinyl, -CH=CH(CH3), -CH=C(CH3)2, -C(CH3)=CH2, -C(CH3)=CH(CH3), -C(CH2CH3)=CH2,
cyclohexenyl, cyclopentenyl, cyclohexadienyl, butadienyl, pentadienyl, and hexadienyl among
others.
[0040] The term "alkynyl" as used herein refers to straight and branched chain alkyl
groups, except that at least one triple bond exists between two carbon atoms. Thus, alkynyl
groups have from 2 to 40 carbon atoms, 2 to about 20 carbon atoms, or from 2 to 12 carbons or,
in some embodiments, from 2 to 8 carbon atoms. Examples include, but are not limited to -
CºCH, -CºC(CH3), -CºC(CH2CH3), -CH2CºCH, -CH2CºC(CH3), and -CH2CºC(CH2CH3)
among others.
[0041] The term "acyl" as used herein refers to a group containing a carbonyl moiety
wherein the group is bonded via the carbonyl carbon atom. The carbonyl carbon atom is also
bonded to another carbon atom, which can be part of an alkyl, aryl, aralkyl cycloalkyl,
cycloalkylalkyl, heterocyclyl, heterocyclylalkyl, heteroaryl, heteroarylalkyl group or the like. In
the special case wherein the carbonyl carbon atom is bonded to a hydrogen, the group is a
"formyl" group, an acyl group as the term is defined herein. An acyl group can include 0 to
about 12-20 or 12-40 additional carbon atoms bonded to the carbonyl group. An acyl group can
include double or triple bonds within the meaning herein. An acryloyl group is an example of an
acyl group. An acyl group can also include heteroatoms within the meaning here. A nicotinoyl
group (pyridyl-3-carbonyl) group is an example of an acyl group within the meaning herein.
Other examples include acetyl, benzoyl, phenylacetyl, pyridylacetyl, cinnamoyl, and acryloyl
groups and the like. When the group containing the carbon atom that is bonded to the carbonyl
carbon atom contains a halogen, the group is termed a "haloacyl" group. An example is a
trifluoro acetyl group.
[0042] The term "cycloalkyl" as used herein refers to cyclic alkyl groups such as, but not
limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl groups.
In some embodiments, the cycloalkyl group can have 3 to about 8-12 ring members, whereas in
other embodiments the number of ring carbon atoms range from 3 to 4, 5, 6, or 7. Cycloalkyl
groups further include polycyclic cycloalkyl groups such as, but not limited to, norbornyl,
adamantyl, bornyl, camphenyl, isocamphenyl, and carenyl groups, and fused rings such as, but
not limited to, decalinyl, and the like. Cycloalkyl groups also include rings that are substituted
with straight or branched chain alkyl groups as defined herein. Representative substituted
cycloalkyl groups can be mono-substituted or substituted more than once, such as, but not
limited to, 2,2-, 2,3-, 2,4- 2,5- or 2,6-disubstituted cyclohexyl groups or mono-, di- or trisubstituted
norbornyl or cycloheptyl groups, which can be substituted with, for example, amino,
hydroxy, cyano, carboxy, nitro, thio, alkoxy, and halogen groups. The term "cycloalkenyl" alone
or in combination denotes a cyclic alkenyl group.
[0043] The term "aryl" as used herein refers to cyclic aromatic hydrocarbons that do not
contain heteroatoms in the ring. Thus aryl groups include, but are not limited to, phenyl,
azulenyl, heptalenyl, biphenyl, indacenyl, fluorenyl, phenanthrenyl, triphenylenyl, pyrenyl,
naphthacenyl, chrysenyl, biphenylenyl, anthracenyl, and naphthyl groups. In some
embodiments, aryl groups contain about 6 to about 14 carbons in the ring portions of the groups.
Aryl groups can be unsubstituted or substituted, as defined herein. Representative substituted
aryl groups can be mono-substituted or substituted more than once, such as, but not limited to, 2-
, 3-, 4-, 5-, or 6-substituted phenyl or 2-8 substituted naphthyl groups, which can be substituted
with carbon or non-carbon groups such as those listed herein.
[0044] The term "aralkyl" as used herein refers to alkyl groups as defined herein in
which a hydrogen or carbon bond of an alkyl group is replaced with a bond to an aryl group as
defined herein. Representative aralkyl groups include benzyl and phenylethyl groups and fused
(cycloalkylaryl)alkyl groups such as 4-ethyl-indanyl. Aralkenyl group are alkenyl groups as
defined herein in which a hydrogen or carbon bond of an alkyl group is replaced with a bond to
an aryl group as defined herein.
[0045] The term "heterocyclyl" as used herein refers to aromatic and non-aromatic ring
compounds containing 3 or more ring members, of which, one or more is a heteroatom such as,
but not limited to, N, O, and S. Thus a heterocyclyl can be a cycloheteroalkyl, or a heteroaryl, or
if polycyclic, any combination thereof. In some embodiments, heterocyclyl groups include 3 to
about 20 ring members, whereas other such groups have 3 to about 15 ring members. A
heterocyclyl group designated as a C2-heterocyclyl can be a 5-ring with two carbon atoms and
three heteroatoms, a 6-ring with two carbon atoms and four heteroatoms and so forth. Likewise
a C 4-heterocyclyl can be a 5-ring with one heteroatom, a 6-ring with two heteroatoms, and so
forth. The number of carbon atoms plus the number of heteroatoms sums up to equal the total
number of ring atoms. A heterocyclyl ring can also include one or more double bonds. A
heteroaryl ring is an embodiment of a heterocyclyl group. The phrase "heterocyclyl group"
includes fused ring species including those that include fused aromatic and non-aromatic groups.
[0046] The term "heterocyclylalkyl" as used herein refers to alkyl groups as defined
herein in which a hydrogen or carbon bond of an alkyl group as defined herein is replaced with a
bond to a heterocyclyl group as defined herein. Representative heterocyclyl alkyl groups
include, but are not limited to, furan-2-yl methyl, furan-3-yl methyl, pyridine-3-yl methyl,
tetrahydrofuran-2-yl ethyl, and indol-2-yl propyl.
[0047] The term "heteroarylalkyl" as used herein refers to alkyl groups as defined herein
in which a hydrogen or carbon bond of an alkyl group is replaced with a bond to a heteroaryl
group as defined herein.
[0048] The term "alkoxy" as used herein refers to an oxygen atom connected to an alkyl
group, including a cycloalkyl group, as are defined herein. Examples of linear alkoxy groups
include but are not limited to methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, and the
like. Examples of branched alkoxy include but are not limited to isopropoxy, sec-butoxy, tertbutoxy,
isopentyloxy, isohexyloxy, and the like. Examples of cyclic alkoxy include but are not
limited to cyclopropyloxy, cyclobutyloxy, cyclopentyloxy, cyclohexyloxy, and the like. An
alkoxy group can include one to about 12-20 or about 12-40 carbon atoms bonded to the oxygen
atom, and can further include double or triple bonds, and can also include heteroatoms. For
example, an allyloxy group is an alkoxy group within the meaning herein. A methoxyethoxy
group is also an alkoxy group within the meaning herein, as is a methylenedioxy group in a
context where two adjacent atoms of a structures are substituted therewith.
[0049] The term "amine" as used herein refers to primary, secondary, and tertiary amines
having, e.g., the formula N(group)3 wherein each group can independently be H or non-H, such
as alkyl, aryl, and the like. Amines include but are not limited to R-NH2, for example,
alkylamines, arylamines, alkylarylamines; R2NH wherein each R is independently selected, such
as dialkylamines, diarylamines, aralkylamines, heterocyclylamines and the like; and R3N
wherein each R is independently selected, such as trialkylamines, dialkylarylamines,
alkyldiarylamines, triarylamines, and the like. The term "amine" also includes ammonium ions
as used herein.
[0050] The term "amino group" as used herein refers to a substituent of the form -NH2, -
NHR, -NR2, -NR3
+, wherein each R is independently selected, and protonated forms of each,
except for -NR3
+, which cannot be protonated. Accordingly, any compound substituted with an
amino group can be viewed as an amine. An "amino group" within the meaning herein can be a
primary, secondary, tertiary or quaternary amino group. An "alkylamino" group includes a
monoalkylamino, dialkylamino, and trialkylamino group.
[0051] The terms "halo" or "halogen" or "halide", as used herein, by themselves or as
part of another substituent mean, unless otherwise stated, a fluorine, chlorine, bromine, or iodine
atom, preferably, fluorine, chlorine, or bromine.
[0052] The term "haloalkyl" group, as used herein, includes mono-halo alkyl groups,
poly-halo alkyl groups wherein all halo atoms can be the same or different, and per-halo alkyl
groups, wherein all hydrogen atoms are replaced by halogen atoms, such as fluoro. Examples of
haloalkyl include trifluoromethyl, 1,1-dichloroethyl, 1,2-dichloroethyl, l,3-dibromo-3,3-
difluoropropyl, perfluorobutyl, and the like.
[0053] The term "hydrocarbon" as used herein refers to a functional group or molecule
that includes carbon and hydrogen atoms. The term can also refer to a functional group or
molecule that normally includes both carbon and hydrogen atoms but wherein all the hydrogen
atoms are substituted with other functional groups.
[0054] The term "solvent" as used herein refers to a liquid that can dissolve a solid,
liquid, or gas. Nonlimiting examples of solvents are silicones, organic compounds, water,
alcohols, ionic liquids, and supercritical fluids.
[0055] The term "room temperature" as used herein refers to a temperature of about 15
°C to 28 °C.
[0056] As used herein, "degree of polymerization" is the number of repeating units in a
polymer.
[0057] As used herein, the term "polymer" refers to a molecule having at least one
repeating unit.
[0058] The term "copolymer" as used herein refers to a polymer that includes at least two
different monomers. A copolymer can include any suitable number of monomers.
[0059] The term "downhole" as used herein refers to under the surface of the earth, such
as a location within or fluidly connected to a wellbore.
[0060] As used herein, the term "drilling fluid" refers to fluids, slurries, or muds used in
drilling operations downhole, such as the formation of the wellbore.
[0061] As used herein, the term "stimulation fluid" refers to fluids or slurries used
downhole during stimulation activities of the well that can increase the production of a well,
including perforation activities. In some examples, a stimulation fluid can include a fracking
fluid, or an acidizing fluid.
[0062] As used herein, the term "clean-up fluid" refers to fluids or slurries used
downhole during clean-up activities of the well, such as any treatment to remove material
obstructing the flow of desired material from the subterranean formation. In one example, a
clean-up fluid can be an acidification treatment to remove material formed by one or more
perforation treatments. In another example, a clean-up fluid can be used to remove a filter cake.
[0063] As used herein, the term "fracking fluid" refers to fluids or slurries used downhole
during fracking operations.
[0064] As used herein, the term "spotting fluid" refers to fluids or slurries used downhole
during spotting operations, and can be any fluid designed for localized treatment of a downhole
region. In one example, a spotting fluid can include a lost circulation material for treatment of a
specific section of the wellbore, such as to seal off fractures in the wellbore and prevent sag. In
another example, a spotting fluid can include a water control material. In some examples, a
spotting fluid can be designed to free a stuck piece of drilling or extraction equipment, can
reduce torque and drag with drilling lubricants, prevent differential sticking, promote wellbore
stability, and can help to control mud weight.
[0065] As used herein, the term "production fluid" refers to fluids or slurries used
downhole during the production phase of a well. Production fluids can include downhole
treatments designed to maintain or increase the production rate of a well, such as perforation
treatments, clean-up treatments, or remedial treatments.
[0066] As used herein, the term "completion fluid" refers to fluids or slurries used
downhole during the completion phase of a well, including cementing compositions.
[0067] As used herein, the term "remedial treatment fluid" refers to fluids or slurries used
downhole for remedial treatment of a well. Remedial treatments can include treatments designed
to increase or maintain the production rate of a well, such as stimulation or clean-up treatments.
[0068] As used herein, the term "abandonment fluid" refers to fluids or slurries used
downhole during or preceding the abandonment phase of a well.
[0069] As used herein, the term "acidizing fluid" refers to fluids or slurries used
downhole during acidizing treatments downhole. In one example, an acidizing fluid is used in a
clean-up operation to remove material obstructing the flow of desired material, such as material
formed during a perforation operation. In some examples, an acidizing fluid can be used for
damage removal.
[0070] As used herein, the term "cementing fluid" refers to fluids or slurries used during
cementing operations of a well. For example, a cementing fluid can include an aqueous mixture
including at least one of cement and cement kiln dust. In another example, a cementing fluid can
include a curable resinous material such as a polymer that is in an at least partially uncured state.
[0071] As used herein, the term "water control material" refers to a solid or liquid
material that interacts with aqueous material downhole, such that hydrophobic material can more
easily travel to the surface and such that hydrophilic material (including water) can less easily
travel to the surface. A water control material can be used to treat a well to cause the proportion
of water produced to decrease and to cause the proportion of hydrocarbons produced to increase,
such as by selectively binding together material between water-producing subterranean
formations and the wellbore while still allowing hydrocarbon-producing formations to maintain
output.
[0072] As used herein, the term "subterranean material" or "subterranean formation"
refers to any material under the surface of the earth, including under the surface of the bottom of
the ocean. For example, a subterranean material can be any section of a wellbore, including any
materials placed into the wellbore such as cement, drill shafts, liners, or screens. In some
examples, a subterranean material can be any section of underground that can produce liquid or
gaseous petroleum materials or water.
[0073] As used herein, the term "hydrocarbyl" refers to a functional group derived from a
straight chain, branched, or cyclic hydrocarbon, such as an alkyl, alkenyl, alkynyl, aryl,
cycloalkyl, acyl, or a combination thereof.
[0074] As used herein, the term "radiation" refers to energetic particles travelling through
a medium or space. Examples of radiation include visible light, infrared light, microwaves, radio
waves, very low frequency waves, extremely low frequency waves, thermal radiation (heat), and
black-body radiation.
[0075] As used herein, the term "condensation" with respect to a chemical reaction refers
to a chemical reaction wherein two molecules combine with the loss of a small molecule such as
water, hydrogen chloride, methanol, acetic acid, or any suitable product of the combination.
Method of using the hollow hydrogel capsule for treatment of a subterranean formation.
[0076] In various embodiments, the present invention provides a method of using a
hydrogel capsule. The method includes obtaining or providing one or more hollow hydrogel
capsules. The hollow hydrogel capsule includes a hydrogel shell. The hydrogel shell includes a
polymerized composition that is hydrolyzed and crosslinked. The pre-polymerized composition
includes at least one vinyl amine. The vinyl amine includes at least one hydrolytically
deprotectable masked primary amine. The pre-polymerized composition also includes at least
one polyvinyl compound. The hydrogel capsule also includes a hollow interior. The hollow
interior includes at least one component of a composition for use downhole. The downhole
composition is for subterranean petroleum or water well drilling, stimulation, clean-up,
production, completion, abandonment, or a combination thereof. The crosslinking of the
hydrolyzed and crosslinked polymerized composition includes crosslinking with at least one
molecule including a plurality of functional groups condensable with primary amines. The
method also includes contacting the hollow hydrogel capsules with a subterranean material
downhole. The method can include releasing downhole at least some or substantially all of the at
least one component of the downhole composition in the hollow interior of the capsule. The
releasing can be localized to one or more specific regions downhole.
[0077] In some embodiments, the method includes providing the hollow hydrogel
capsules in a composition that includes that hollow hydrogel capsules. Likewise, the contacting
of the hollow hydrogel capsules with the subterranean material downhole can be contacting the
composition that includes the capsules with the subterranean material downhole. The
composition that includes the hydrogel capsules can be any suitable composition that includes
that hydrogel capsules. For example, the composition that includes the hydrogel capsules can be
a downhole composition for subterranean petroleum or water well drilling, stimulation, clean-up,
production, completion, abandonment, or a combination thereof. The downhole composition for
subterranean petroleum or water well drilling, stimulation, clean-up, production, completion,
abandonment, or a combination thereof can include at least one of a drilling fluid, stimulation
fluid, fracking fluid, spotting fluid, clean-up fluid, production fluid, completion fluid, remedial
treatment fluid, abandonment fluid, pill, acidizing fluid, and a cementing fluid.
[0078] The method can include triggering the release of at least some of the at least one
component of the downhole composition in the hollow interior of at least some of the hollow
hydrogel capsules. The triggering can occur downhole, or above ground. The triggering can
include at least one of acid-triggered, caustic material-triggered, heat-triggered, light-triggered,
radiation-triggered, chemically-triggered, natural decay of materials within the capsule or of the
capsule themselves, and vibration, acoustic, or agitation-triggered. The triggering can include
triggering a gradual release of at least some of the at least one component of the downhole
composition in the hollow interior of at least some of the hollow hydrogel capsules. The
triggering can include triggering a fast release of substantially all of the at least one component
of the downhole composition in the hollow interior of at least some of the hollow hydrogel
capsules. The triggering can include an acid of caustic material reacting with the hydrogel
capsule walls thereby increasing the permeability thereof, wherein the acid or caustic material is
at least one of within and outside of the hollow hydrogel capsule.
[0079] The triggering can include heating the hydrogel capsule. The heating of the
hydrogel capsule can occur within the capsule, at least one of in and on the hydrogel shell of the
capsule, outside the hydrogel shell of the capsule, or a combination thereof. In some
embodiments, the heating occurs within the capsule due at least in part to a chemical reaction of
materials therein. In some embodiments, the heating is at least in part caused by heating of metal
nanoparticles, wherein the metal nanoparticles are at least one of in or on the hydrogel shell of
the capsule.
[0080] The triggering can include applying radiation to the hydrogel capsule. The
radiation can be light, such as any suitable light. The light can be laser light. The radiation can
cause heating of metal nanoparticles, wherein the metal nanoparticles are at least one of on and
in the hydrogel shell of the capsule.
[0081] The triggering can be a chemical reaction that increases the permeability of the
hydrogel shell, wherein the chemical reaction occurs at least one of within the capsule and
outside of the capsule. The chemical reaction can produce at least one of heat and a material that
reacts with the hydrogel shell thereby increasing the permeability of the hydrogel shell. The
triggering can be vibrating or agitating the hydrogel capsules thereby increasing the permeability
thereof. The vibrating or agitating can puncture or tear the hydrogel shells.
[0082] In some embodiments, the method of using the hydrogel capsules is a method of
at least one of reducing viscosity downhole of a composition and increasing dispersion downhole
of one medium in another medium. In such a method, the hydrogel capsules can include a cargo
that is a component of a composition including at least one of a drilling fluid, stimulation fluid,
fracking fluid, spotting fluid, clean-up fluid, production fluid, completion fluid, remedial
treatment fluid, abandonment fluid, pill, acidizing fluid, and a cementing fluid. In addition, the
at least one component of the downhole composition in the hollow interior of the one or more
hollow hydrogel capsules can be at least one of a breaker, a surfactant, a dispersant, and a
diluent.
[0083] In some embodiments, the method of using the hydrogel capsules is a method of
increasing viscosity downhole of a drilling fluid, stimulation fluid, fracking fluid, spotting fluid,
clean-up fluid, production fluid, completion fluid, remedial treatment fluid, abandonment fluid,
pill, acidizing fluid, cementing fluid, or a combination thereof. In such a method, the hydrogel
capsules can be a component of a composition including at least one of a drilling fluid,
stimulation fluid, fracking fluid, spotting fluid, clean-up fluid, production fluid, completion fluid,
remedial treatment fluid, abandonment fluid, pill, acidizing fluid, and a cementing fluid. In
addition, the at least one component of the downhole composition in the hollow interior of the
one or more hollow hydrogel capsules can be a crosslinker.
[0084] In some embodiments, the method of using the hydrogel capsules is a method of
forming a cement downhole having increased porosity or of modifying the density downhole of a
drilling fluid, stimulation fluid, fracking fluid, spotting fluid, clean-up fluid, production fluid,
completion fluid, remedial treatment fluid, abandonment fluid, pill, acidizing fluid, cementing
fluid, or a combination thereof. In such a method, the hydrogel capsules can be a component of
a composition including at least one of a drilling fluid, stimulation fluid, fracking fluid, spotting
fluid, clean-up fluid, production fluid, completion fluid, remedial treatment fluid, abandonment
fluid, pill, acidizing fluid, cementing fluid, and a combination thereof. In addition, the at least
one component of the downhole composition in the hollow interior of the one or more hollow
hydrogel capsules can be a gas.
[0085] In some embodiments, the method of using the hydrogel capsules is a method of
modifying viscosity downhole of a drilling fluid, stimulation fluid, fracking fluid, spotting fluid,
clean-up fluid, production fluid, completion fluid, remedial treatment fluid, abandonment fluid,
pill, acidizing fluid, cementing fluid, or a combination thereof. In such a method, the hydrogel
capsules can be a component of a composition including at least one of a drilling fluid,
stimulation fluid, fracking fluid, spotting fluid, clean-up fluid, production fluid, completion fluid,
remedial treatment fluid, abandonment fluid, pill, acidizing fluid, and cementing fluid. In
addition, the at least one component of the downhole composition in the hollow interior of the
one or more hollow hydrogel capsules can include be viscosity modifier.
[0086] In some embodiments, the method of using the hydrogel capsules is a method of
modifying density downhole of a drilling fluid, stimulation fluid, fracking fluid, spotting fluid,
clean-up fluid, production fluid, completion fluid, remedial treatment fluid, abandonment fluid,
pill, acidizing fluid, cementing fluid, or a combination thereof. In such a method, the hydrogel
capsules can be a component of a composition including at least one of a drilling fluid,
stimulation fluid, fracking fluid, spotting fluid, clean-up fluid, production fluid, completion fluid,
remedial treatment fluid, abandonment fluid, pill, acidizing fluid, and a cementing fluid. In
addition, the at least one component of the downhole composition in the hollow interior of the
one or more hollow hydrogel capsules can be a density control agent.
[0087] In some embodiments, the method of using the hydrogel capsules is a method of
adding pigment, dye, or marker downhole to a drilling fluid, stimulation fluid, fracking fluid,
spotting fluid, clean-up fluid, production fluid, completion fluid, remedial treatment fluid,
abandonment fluid, pill, acidizing fluid, cementing fluid, or a combination thereof. In such a
method, the hydrogel capsules can be a component of a composition including at least one of a
drilling fluid, stimulation fluid, fracking fluid, spotting fluid, clean-up fluid, production fluid,
completion fluid, remedial treatment fluid, abandonment fluid, pill, acidizing fluid, and a
cementing fluid. In addition, the at least one component of the downhole composition in the
hollow interior of the one or more hollow hydrogel capsules can be at least one of a pigment,
dye, marker.
[0088] In some embodiments, the method of using the hydrogel capsules is a method of
accelerating curing downhole of cement or resin, such as an aqueous mixture including at least
one of cement and cement kiln dust, or a resin. In such a method, the hydrogel capsules can be a
component of a composition including a cementing fluid, such as an aqueous mixture including
at least one of cement and cement kiln dust, or a resin. In addition, the at least one component of
the downhole composition in the hollow interior of the one or more hollow hydrogel capsules
can be a curing accelerator, such as a cement-curing accelerator or a resin-curing accelerator.
[0089] In some embodiments, the method of using the hydrogel capsules if a method of
retarding curing downhole of a cement or resin, such as an aqueous mixture including at least
one of cement and cement kiln dust, or a resin. In such a method, the hydrogel capsules can be a
component of a composition including a cementing fluid, such as an aqueous mixture including
at least one of cement and cement kiln dust, or a resin. In addition, the at least one component of
the downhole composition in the hollow interior of the one or more hollow hydrogel capsules
can be a curing retarder, such as a cement-curing retarder or a resin-curing retarder.
Hollow hydrogel capsule composition for treatment of a subterranean formation.
[0090] In various embodiments, the present invention provides a hydrogel capsule
composition. The hydrogel capsule composition includes at least one hollow hydrogel capsule.
The hollow hydrogel capsule includes a hydrogel shell. The hydrogel shell includes a
polymerized composition that is hydrolyzed and crosslinked. The pre-polymerized composition
includes at least one vinyl amine. The vinyl amine includes at least one hydrolytically
deprotectable masked primary amine. The pre-polymerized composition also includes at least
one polyvinyl compound. The hydrogel capsule also includes a hollow interior. The hollow
interior includes at least one component of a composition for use downhole. The downhole
composition is for subterranean petroleum or water well drilling, stimulation, clean-up,
production, completion, abandonment, or a combination thereof. The crosslinking of the
hydrolyzed and crosslinked polymerized composition includes crosslinking with at least one
molecule including a plurality of functional groups condensable with primary amines. In
examples, the hollow hydrogel capsule composition can include any suitable component in
addition to the at least one hollow hydrogel capsule. The hydrogel capsule can be present in any
suitable wt% in the composition. For example, the hydrogel capsule can be present in about
0.000,001 wt% or less, or about 0.000,01%, 0.000,1%, 0.001%, 0.01, 0.1, 1, 2, 3, 4, 5, 10, 15, 20,
30, 40, 50, 60, 70, 80, 85, 90, 95, 96, 97, 98, 99, 99.9, 99.99, 99.999, 99.999,9, or about
99.999,99 wt% or more of the composition. Upon the release of the cargo, the properties of the
composition can be modified, including any suitable property consistent with the cargo described
herein, for example density, viscosity, cure rate, pH, or chemical composition. In some
examples, upon release of the cargo, the cargo chemically reacts with at least one component of
the composition, causing the desired modification of the property of the composition.
[0091] In various embodiments, the hydrogel capsule composition also includes a
downhole composition for subterranean petroleum or water well drilling, stimulation, clean-up,
production, completion, abandonment, or a combination thereof. The downhole composition for
subterranean petroleum or water well drilling, stimulation, clean-up, production, completion,
abandonment, or a combination thereof can include a drilling fluid, stimulation fluid, fracking
fluid, spotting fluid, clean-up fluid, production fluid, completion fluid, remedial treatment fluid,
abandonment fluid, pill, acidizing fluid, cementing fluid, or a combination thereof.
[0092] A drilling fluid, also known as a drilling mud or simply "mud," is a specially
designed fluid that is circulated through a wellbore as the wellbore is being drilled to facilitate
the drilling operation. The drilling fluid can carry cuttings up from beneath and around the bit,
transport them up the annulus, and allow their separation. Also, a drilling fluid can cool and
lubricate the drill head as well as reducing friction between the drill string and the sides of the
hole. The drilling fluid aids in support of the drill pipe and drill head, and provides a hydrostatic
head to maintain the integrity of the wellbore walls and prevent well blowouts. Specific drilling
fluid systems can be selected to optimize a drilling operation in accordance with the
characteristics of a particular geological formation. The drilling fluid can be formulated to
prevent unwanted influxes of formation fluids from permeable rocks penetrated and also to form
a thin, low permeability filter cake which temporarily seals pores, other openings, and formations
penetrated by the bit. In water-based drilling fluids, solid particles are suspended in a water or
brine solution containing other components. Oils or other non-aqueous liquids can be emulsified
in the water or brine or at least partially solubilized (for less hydrophobic non-aqueous liquids),
but water is the continuous phase. In oil-based drilling fluids, solid particles are suspended in a
continuous oil-based phase, and can optionally include an emulsified aqueous phase.
[0093] One or more hydrogel capsules can form a useful combination with drilling fluid.
For example, the cargo of the capsule can be used to modify the viscosity of the drilling fluid at a
desired time or in a desired place, such as before or after placing the drilling fluid downhole, or
before, during, or after contacting a subterranean material with the drilling fluid. In some
embodiments, the composition advantageously allows adjustment of the viscosity or other
properties of the drilling fluid as needed while the drilling fluid is being used. In some
examples, the composition allows the viscosity or other properties of the drilling fluid to be
adjusted such that in one or more locations of the borehole the drilling fluid has one particular set
of properties associated with contacting with the cargo of the hollow capsules, while in one or
more other locations of the borehole the drilling fluid has different properties due to not being
contacted with the cargo of the capsules. For example, during a drilling process, pressure can
build up in the borehole due for example to penetration of the drill bit into a particular formation.
The hollow hydrogel capsules can be triggered to release a particular cargo in the desired
location such as near or above the pressure release, for example increasing the viscosity or
density of the drilling fluid, thus timely preventing the increased pressure from causing a
blowout or other undesirable consequences. In another example, during the drilling of porous
material such as shale it can be desirable to prevent the influx of drilling fluid into the pores of
the material to retain the stability of the material and thus of the stability of the borehole through
the material. In some embodiments of the present invention, the viscosity of the drilling fluid
proximate to the porous material can be increased to help prevent the influx of drilling fluid into
the porous material, and thus preserve the integrity of the borehole.
[0094] A water-based drilling fluid in embodiments of the composition of the present
invention can be any suitable water-based drilling fluid. In various embodiments, the drilling
fluid can include at least one of water (fresh or brine), a salt (e.g., calcium chloride, sodium
chloride, potassium chloride, magnesium chloride, calcium bromide, sodium bromide, potassium
bromide, calcium nitrate, sodium formate, potassium formate, cesium formate), aqueous base
(e.g., sodium hydroxide or potassium hydroxide), alcohol or polyol, cellulose, starches, alkalinity
control agents, density control agents such as a density modifier (e.g. barium sulfate), surfactants
(e.g. betaines, alkali metal alkylene acetates, sultaines, ether carboxylates), emulsifiers,
dispersants, polymeric stabilizers, crosslinking agents, polyacrylamides, polymers or
combinations of polymers, antioxidants, heat stabilizers, foam control agents, solvents, diluents,
plasticizers, filler or inorganic particles (e.g. silica), pigments, dyes, precipitating agents (e.g.,
silicates or aluminum complexes), and rheology modifiers such as thickeners or viscosifiers (e.g.
xanthan gum). Any ingredient listed in this paragraph can be either present or not present in the
composition. A drilling fluid can be present in the composition in any suitable amount, such as
about 1 wt or less, about 2 wt , 3, 4, 5, 10, 15, 20, 30, 40, 50, 60, 70, 80, 85, 90, 95, 96, 97,
98, 99, 99.9, 99.99, 99.999, or about 99.9999 wt or more of the composition.
[0095] An oil-based drilling fluid or mud in embodiments of the composition of the
present invention can be any suitable oil-based drilling fluid. In various embodiments the
drilling fluid can include at least one of a based oil (or synthetic fluid), saline, aqueous solution,
emulsifiers, other agents of additives for suspension control, weight or density control, oilwetting
agents, fluid loss or filtration control agents, and rheology control agents. For example,
see H. C. H. Darley and George R. Gray, Composition and Properties of Drilling and Completion
Fluids 66-67, 561-562 (5th ed. 1988). An oil-based or invert emulsion-based drilling fluid can
include between about 50:50 to about 95:5 by volume of oil phase to water phase. A
substantially all oil mud includes about 100% liquid phase oil by volume; e.g., substantially no
internal aqueous phase.
[0096] The composition can include an aqueous mixture of at least one of cement and
cement kiln dust. The hydrogel capsule can form a useful combination with cement or cement
kiln dust, for example by modifying the viscosity or other properties of the cement at a desired
time or in a desired place, or by creating a porous cement using hydrogel capsules having a
gaseous cargo. For example, during the cementing phase of forming a well for petroleum
extraction, some or parts of a particular borehole may require a thicker cement composition to
allow the cement composition to properly set or to behave in another desired manner, while other
parts of the borehole may not require as thick of a cement. A thicker cement can be more
difficult to pump downhole. Various embodiments of the present invention allow for thickening
of the cement or variation of other properties of the cement near or at the location where the
thickened or otherwise modified material is desired. In another example, embodiments allow
variation of the viscosity or other properties of the cement pumped downhole, such that a thicker
or otherwise modified portion of cement can be placed downhole before, after, or between
segments of cements having lower viscosity or other different properties. In another example,
other properties of the cement near or at a desired location can be advantageously varied
downhole.
[0097] The cement kiln dust can be any suitable cement kiln dust. Cement kiln dust can
be formed during the manufacture of cement and can be partially calcined kiln feed which is
removed from the gas stream and collected in a dust collector during manufacturing process.
Cement kiln dust can be advantageously utilized in a cost-effective manner since kiln dust is
often regarded as a low value waste product of the cement industry. Some embodiments of the
composition can include cement kiln dust but no cement, cement kiln dust and cement, or cement
but no cement kiln dust. The cement can be any suitable cement. The cement can be a hydraulic
cement. A variety of cements can be utilized in accordance with the present invention, for
example, those including calcium, aluminum, silicon, oxygen, iron, or sulfur, which can set and
harden by reaction with water. Suitable cements can include Portland cements, pozzolana
cements, gypsum cements, high alumina content cements, slag cements, silica cements, and
combinations thereof. In some embodiments, the Portland cements that are suitable for use in
the present invention are classified as Classes A, C, H, and G cements according to the American
Petroleum Institute, API Specification for Materials and Testingfor Well Cements, API
Specification 10, Fifth Ed., Jul. 1, 1990. A cement can be generally included in the composition
in an amount sufficient to provide the desired compressive strength, density, or cost. In some
embodiments, the hydraulic cement can be present in the composition in an amount in the range
of from 0 wt to about 100 wt , 0-95 wt , 20-95 wt , or about 50-90 wt . A cement kiln
dust can be present in an amount of at least about 0.01 wt , or about 5 wt - 80 wt , or about
10 wt to about 50 wt .
[0098] Optionally, other additives can be added to a cement or kiln dust-containing
composition of the present invention as deemed appropriate by one skilled in the art, with the
benefit of this disclosure. Any optional ingredient listed in this paragraph can be either present
or not present in the composition. For example, the composition can include fly ash, metakaolin,
shale, zeolite, set retarding additive, surfactant, a gas, accelerators, weight reducing additives,
heavy-weight additives, lost circulation materials, filtration control additives, dispersants, and
combinations thereof. In some examples, additives can include crystalline silica compounds,
amorphous silica, salts, fibers, hydratable clays, microspheres, pozzolan lime, thixotropic
additives, combinations thereof, and the like.
[0099] A pill is a relatively small quantity (e.g. less than about 500 bbl, or less than about
200 bbl) of drilling fluid used to accomplish a specific task that the regular drilling fluid cannot
perform. For example, a pill can be a high-viscosity pill to, for example, help lift cuttings out of
a vertical wellbore. In another example, a pill can be a freshwater pill to, for example, dissolve a
salt formation. Another example is a pipe-freeing pill to, for example, destroy filter cake and
relieve differential sticking forces. In another example, a pill is a lost circulation material pill to,
for example, plug a thief zone. A pill can include any component described herein as a
component of a drilling fluid.
Hollow hydrogel capsule.
[00100] In various embodiments, the present invention provides a hollow hydrogel
capsule. The hollow hydrogel capsule includes a hydrogel shell. The hydrogel shell includes a
polymerized composition that is hydrolyzed and crosslinked. The pre-polymerized composition
includes at least one vinyl amine. The vinyl amine includes at least one hydrolytically
deprotectable masked primary amine. The pre-polymerized composition also includes at least
one polyvinyl compound. The hydrogel capsule also includes a hollow interior. The hollow
interior includes at least one component of a composition for use downhole. The downhole
composition is for subterranean petroleum or water well drilling, stimulation, clean-up,
production, completion, abandonment, or a combination thereof. The crosslinking of the
hydrolyzed and crosslinked polymerized composition includes crosslinking with at least one
molecule including a plurality of functional groups condensable with primary amines.
[00101] The hollow interior of the capsule includes a cargo, wherein the cargo is at least
one component of a composition for use downhole for subterranean petroleum or water well
drilling, stimulation, clean-up, production, completion, abandonment, or a combination thereof.
The composition for subterranean petroleum or water well drilling, stimulation, clean-up,
production, completion, abandonment, or a combination thereof can be any suitable drilling
fluid, stimulation fluid, fracking fluid, spotting fluid, clean-up fluid, production fluid, completion
fluid, remedial treatment fluid, abandonment fluid, pill, acidizing fluid, cementing fluid, or a
combination thereof. The component of the composition for use downhole can be any suitable
component, particularly a component that is advantageously delivered in a targeted fashion with
respect to at least one of time, location, and rate of release. In some examples, the component of
the composition for use downhole can be water, saline, salt, aqueous base, oil, organic solvent,
synthetic fluid oil phase, aqueous solution, alcohol or polyol, cellulose, starch, alkalinity control
agent, density control agent, density modifier, surfactant, emulsifier, dispersant, polymeric
stabilizer, crosslinking agent, polyacrylamide, polymer or combination of polymers, antioxidant,
heat stabilizer, foam control agent, solvent, diluent, plasticizer, filler or inorganic particle,
pigment, dye, precipitating agent, rheology modifier, oil-wetting agent, set retarding additive,
surfactant, gas, accelerator, weight reducing additive, heavy-weight additive, lost circulation
material, filtration control additive, dispersant, salts, fiber, thixotropic additive, breaker,
crosslinker, gas, rheology modifier, density control agent, curing accelerator (e.g., cement-curing
accelerator or resin-curing accelerator), curing retarder (e.g., cement-curing retarder or resincuring
retarder), pH modifier, chelating agent, scale inhibitor, enzyme, resin, water control
material, polymer, oxidizer, and a marker (e.g., a radioactive marker, fluorescent marker, or
other marker). The hollow interior can include a solvent, such as a solution including a solvent.
The solvent can be any suitable solvent, such as water; the solution can be an aqueous solution.
[00102] The pre-polymerized composition includes at least one vinyl amine. The vinyl
amine includes at least one hydro lytically deprotectable masked primary amine. The
hydro lytically deprotectable masked primary amine can be any functional group that can be
exposed to hydrolytic conditions (e.g., acidic or

CLAIMS
What is claimed is:
1. A method of treating a subterranean formation, the method comprising:
obtaining or providing one or more hollow hydrogel capsules comprising
a hydrogel shell comprising a hydrolyzed and crosslinked polymerized
composition, the pre-polymerized composition comprising
at least one vinyl amine comprising at least one hydrolytically
deprotectable masked primary amine, and
at least one polyvinyl compound; and
a hollow interior comprising at least one component of a downhole composition
for subterranean petroleum or water well drilling, stimulation, clean-up, production, completion,
abandonment, or a combination thereof,
wherein the crosslinking comprises crosslinking with at least one molecule
comprising a plurality of functional groups condensable with primary amines; and
contacting the hollow hydrogel capsules with a subterranean material downhole.
2. The method of claim 1, further comprising releasing downhole at least some or
substantially all of the at least one component of the downhole composition in the hollow interior
of the capsule.
3. The method of claim 2, wherein the releasing is localized to one or more specific regions
downhole.
4. The method of claim 1, further comprising triggering the release of at least some of the at
least one component of the downhole composition in the hollow interior of at least some of the
hollow hydrogel capsules.
5. The method of claim 4, wherein the triggering occurs downhole.
6. The method of claim 4, wherein the triggering comprises acid-triggered, caustic materialtriggered,
heat-triggered, light-triggered, radiation-triggered, chemically-triggered, natural
decay-triggered, vibration-triggered, acoustic-triggered, agitation-triggered, or a combination
thereof.
7. The method of claim 4, wherein the triggering comprises triggering a gradual release of
at least some of the at least one component of the downhole composition in the hollow interior of
at least some of the hollow hydrogel capsules.
8. The method of claim 4, wherein the triggering comprises triggering a fast release of
substantially all of the at least one component of the downhole composition in the hollow interior
of at least some of the hollow hydrogel capsules.
9. The method of claim 4, wherein the triggering comprises an acid or caustic material
reacting with the hydrogel capsule walls thereby increasing the permeability thereof, wherein the
acid or caustic material is at least one of within and outside of the hollow hydrogel capsule.
10. The method of claim 4, wherein the triggering comprises heating the hydrogel capsule.
11. The method of claim 10, wherein the heating occurs within the capsule, the heating
occurs at least one of in and on the hydrogel shell of the capsule, the heating occurs outside the
hydrogel shell of the capsule, or a combination thereof.
12. The method of claim 11, wherein the heating occurs within the capsule due at least in part
to a chemical reaction of materials therein.
13. The method of claim 11, wherein the heating is at least in part caused by heating of metal
nanoparticles, wherein the metal nanoparticles are in the hydrogel shell of the capsule, on the
hydrogel shell of the capsule, or a combination thereof.
14. The method of claim 4, wherein the triggering comprises applying radiation to the
hydrogel capsule.
15. The method of claim 14, wherein the radiation comprises light.claim 16. The method of
claim 15, wherein the radiation comprises laser light.
17. The method of claim 14, wherein the radiation causes heating of metal nanoparticles,
wherein the metal nanoparticles are in the hydrogel shell of the capsule, on the hydrogel shell of
the capsule, or a combination thereof.
18. The method of claim 4, wherein the triggering comprises a chemical reaction that
increases the permeability of the hydrogel shell, wherein the chemical reaction occurs within the
capsule, outside of the capsule, or a combination thereof.
19. The method of claim 18, wherein the chemical reaction produces at least one of heat and
a material that reacts with the hydrogel shell thereby increasing the permeability thereof.
20. The method of claim 4, wherein the triggering comprises vibrating or agitating the
hydrogel capsules thereby increasing the permeability thereof.
2 1. The method of claim 20, wherein the permeability is increased at least due to rupturing
the hydrogel shell, tearing the hydrogel shell, puncturing the hydrogel shell, or a combination
thereof.
22. The method of claim 1, wherein obtaining or providing the hollow hydrogel capsules
comprises obtaining or providing a composition comprising the hollow hydrogel capsules, and
wherein contacting the hollow hydrogel capsules with the subterranean material downhole
comprises contacting the composition comprising the hydrogel capsules with the subterranean
material downhole.
23. The method of claim 22, wherein the composition comprising the hollow hydrogel
capsules comprises a downhole composition for subterranean petroleum or water well drilling,
stimulation, clean-up, production, completion, abandonment, or a combination thereof.
24. The method of claim 23, wherein the downhole composition for subterranean petroleum
or water well drilling, stimulation, clean-up, production, completion, abandonment, or a
combination thereof comprises at least one of a drilling fluid, stimulation fluid, fracking fluid,
spotting fluid, clean-up fluid, production fluid, completion fluid, remedial treatment fluid,
abandonment fluid, pill, acidizing fluid, cementing fluid, or a combination thereof.
25. The method of claim 24, wherein the method is a method of reducing viscosity downhole
of the drilling fluid, stimulation fluid, fracking fluid, spotting fluid, clean-up fluid, production
fluid, completion fluid, remedial treatment fluid, abandonment fluid, pill, acidizing fluid,
cementing fluid, or a combination thereof, of increasing dispersion downhole of one medium in
another medium, or a combination thereof; and wherein the at least one component of the
downhole composition in the hollow interior of the one or more hollow hydrogel capsules
comprises a breaker, a surfactant, a dispersant, a diluent, or a combination thereof.
26. The method of claim 24, wherein the method is a method of increasing viscosity
downhole of the drilling fluid, stimulation fluid, fracking fluid, spotting fluid, clean-up fluid,
production fluid, completion fluid, remedial treatment fluid, abandonment fluid, pill, acidizing
fluid, cementing fluid, or a combination thereof; and wherein the at least one component of the
downhole composition in the hollow interior of the one or more hollow hydrogel capsules
comprises a crosslinker.
27. The method of claim 24, wherein the method is a method of forming a cement downhole
having increased porosity or modifying the density downhole of the drilling fluid, stimulation
fluid, fracking fluid, spotting fluid, clean-up fluid, production fluid, completion fluid, remedial
treatment fluid, abandonment fluid, pill, acidizing fluid, cementing fluid, or a combination
thereof; and wherein the at least one component of the downhole composition in the hollow
interior of the one or more hollow hydrogel capsules comprises a gas.
28. The method of claim 24, wherein the method is a method of modifying viscosity
downhole of the drilling fluid, stimulation fluid, fracking fluid, spotting fluid, clean-up fluid,
production fluid, completion fluid, remedial treatment fluid, abandonment fluid, pill, acidizing
fluid, cementing fluid, or a combination thereof; and wherein the at least one component of the
downhole composition in the hollow interior of the one or more hollow hydrogel capsules
comprises a viscosity modifier.
29. The method of claim 24, wherein the method is a method of modifying density downhole
of the drilling fluid, stimulation fluid, fracking fluid, spotting fluid, clean-up fluid, production
fluid, completion fluid, remedial treatment fluid, abandonment fluid, pill, acidizing fluid,
cementing fluid, or a combination thereof; and wherein the at least one component of the
downhole composition in the hollow interior of the one or more hollow hydrogel capsules
comprises a density control agent.
30. The method of claim 24, wherein the method is a method of adding pigment, dye, or
marker downhole to the drilling fluid, stimulation fluid, fracking fluid, spotting fluid, clean-up
fluid, production fluid, completion fluid, remedial treatment fluid, abandonment fluid, pill,
acidizing fluid, cementing fluid, the subterranean material, or a combination thereof; and
wherein the at least one component of the downhole composition in the hollow interior of the
one or more hollow hydrogel capsules comprises at least one of a pigment, dye, marker.
31. The method of claim 24, wherein the method is a method of accelerating curing
downhole of cement or resin; wherein the composition comprising the hollow hydrogel capsules
comprises a resin or an aqueous mixture comprising cement, cement kiln dust, or a combination
thereof; and wherein the at least one component of the downhole composition in the hollow
interior of the one or more hollow hydrogel capsules comprises a curing accelerator.
32. The method of claim 24, wherein the method is a method for retarding curing downhole
of cement or resin; wherein the composition comprising the hollow hydrogel capsules comprises
a resin or an aqueous mixture comprising cement, cement kiln dust, or a combination thereof;
and wherein the at least one component of the downhole composition in the hollow interior of
the one or more hollow hydrogel capsules comprises a curing retarder.
33. The method of claim 25, wherein the at least one component of the downhole
composition in the hollow interior of the one of more hollow hydrogel capsules is at least
partially released downhole.
34. A hollow hydrogel capsule for treatment of a subterranean formation comprising:
a hydrogel shell comprising a hydrolyzed and crosslinked polymerized composition, the
pre-polymerized composition comprising
at least one vinyl amine comprising at least one hydrolytically deprotectable
masked primary amine, and
at least one polyvinyl compound; and
a hollow interior comprising at least one component of a downhole composition for
subterranean petroleum or water well drilling, stimulation, clean-up, production, completion,
abandonment, or a combination thereof;
wherein the crosslinking comprises crosslinking with at least one molecule comprising a
plurality of functional groups condensable with primary amines.
35. The hollow hydrogel capsule of claim 34, wherein the composition for subterranean
petroleum or water well drilling, stimulation, clean-up, production, completion, abandonment, or
a combination thereof comprises a drilling fluid, stimulation fluid, fracking fluid, spotting fluid,
clean-up fluid, production fluid, completion fluid, remedial treatment fluid, abandonment fluid,
pill, acidizing fluid, cementing fluid, or a combination thereof.
36. The hollow hydrogel capsule of claim 34, wherein the interior of the capsule comprises
water, saline, salt, aqueous base, oil, organic solvent, synthetic fluid oil phase, aqueous solution,
alcohol or polyol, cellulose, starch, alkalinity control agent, density control agent, density
modifier, surfactant, emulsifier, dispersant, polymeric stabilizer, crosslinking agent,
polyacrylamide, polymer or combination of polymers, antioxidant, heat stabilizer, foam control
agent, solvent, diluent, plasticizer, filler or inorganic particle, pigment, dye, precipitating agent,
rheology modifier, oil-wetting agent, set retarding additive, surfactant, gas, accelerator, weight
reducing additive, heavy-weight additive, lost circulation material, filtration control additive,
dispersant, salts, fiber, thixotropic additive, breaker, crosslinker, gas, rheology modifier, density
control agent, curing accelerator, curing retarder, pH modifier, chelating agent, scale inhibitor,
enzyme, resin, water control material, polymer, oxidizer, a marker, or a combination thereof.
37. The hollow hydrogel capsule of claim 34, wherein the interior of the capsule comprises a
release modifier.
38. The hollow hydrogel capsule of claim 37, wherein the release modifier comprises an
organic acid, mineral acid, caustic material, heat-activated material, oxidizer, enzyme, a
nanoparticle, or a combination thereof.
39. The hollow hydrogel capsule of claim 34, wherein the hollow interior comprises a
solvent.
40. The hollow hydrogel capsule of claim 34, wherein the hollow interior comprises water.
41. The hollow hydrogel capsule of claim 34, wherein the hollow interior comprises an
aqueous solution.
42. The hollow hydrogel capsule of claim 34, wherein the hydrolytically deprotectable
masked primary amine is selected from the group consisting of an acylamine group, a
formylamine group, an acetylamine group, a haloacetylamine group, a cyano group, a
thioacylamine group, a carbamate group, and a benzoyl group.
The hollow hydrogel capsule of claim 34, wherein the hydrolytically deprotectable
wherein R1 is independently at each occurrence selected from the group selected from H and (Ci-
Cio)alkyl.
44. The hollow hydrogel capsule of claim 34, wherein the vinyl amine comprising the
masked primary amine has one vinyl group and one masked primary amine.
45. The hollow hydrogel capsule of claim 44, wherein the vinyl amine is linked to the
masked primary amine via a linking group.
46. The hollow hydrogel capsule of claim 34, wherein the vinyl amine comprising the
masked primary amine has the following structure
wherein each of R2, R3, and R4 independently at each occurrence is selected from the
group consisting of hydrogen, F, CI, Br, I, CN, CF3, OCF3, (Ci-Cio)alkoxy, and (Ci-Cio)alkyl;
wherein L1 is selected from the group consisting of a bond, O, S, C(O), S(O),
methylenedioxy, ethylenedioxy, NR, SR2, S0 2R, S0 2NR, S0 3, C(0)C(0), C(0)CH 2C(0), C(S),
C(0)0, OC(O), OC(0)0, C(0)NR, OC(0)NR, C(S)NR, (CH2)0-2NHC(O), N(R)N(R)C(0),
N(R)N(R)C(0)0, N(R)N(R)C(0)NR, N(R)S0 2, N(R)S0 2NR, N(R)C(0)0, N(R)C(0),
N(R)C(S), N(R)C(0)NR, N(R)C(S)NR, N(C(0)R)C(0), N(OR), C(=NH)NR, C(0)N(OR),
C(=NOR), (Ci-C30)alkylene, (C2-C30)alkenylene, (C2-C30)alkynylene, (Ci-C30)haloalkylene, ( -
C3o)alkoxylene, (Ci-C3o)haloalkoxylene, (C4 -C3o)cycloalkyl(Co-C3o)alkylene, (CiC3o)
heterocyclyl(Co-C3o)alkylene, (C6-C3o )aryl(Co-C3o)alkylene, and (Ci-C3o)heteroaryl(Co-
C3o)alkylene, wherein each alkylene, alkenylene, alkynylene, haloalkylene, alkoxylene,
haloalkoxylene, cycloalkylene, arylene, heterocyclylene, and heteroarylene is independently
unsubstituted or further substituted with at least one J ;
wherein J independently at each occurrence is selected from the group consisting of F, CI,
Br, I, OR, CN, CF3, OCF3, R, O, S, C(O), S(O), methylenedioxy, ethylenedioxy, N(R)2, SR,
S(0)R, S0 2R, S0 2N(R)2, S0 3R, C(0)R, C(0)C(0)R, C(0)CH 2C(0)R, C(S)R, C(0)OR,
OC(0)R, OC(0)OR, C(0)N(R) 2, OC(0)N(R) 2, C(S)N(R)2, (CH2)0-2NHC(O)R,
N(R)N(R)C(0)R, N(R)N(R)C(0)OR, N(R)N(R)C(0)N(R) 2, N(R)S0 2R, N(R)S0 2N(R)2,
N(R)C(0)OR, N(R)C(0)R, N(R)C(S)R, N(R)C(0)N(R) 2, N(R)C(S)N(R) 2, N(C(0)R)C(0)R,
N(OR)R, C(=NH)N(R)2, C(0)N(OR)R, and C(=NOR)R, wherein each alkyl, cycloalkyl,
cycloalkylalkyl, aryl, aralkyl, heterocyclyl, heterocyclylalkyl, heteroaryl, and heteroarylalkyl is
independently unsubstituted or substituted with 1-3 J ;
wherein R independently at each occurrence is selected from the group consisting of
hydrogen, (Ci-Cio)alkyl, (C4-Ci0)cycloalkyl, (C4-Ci0)cycloalkyl(Ci-Ci 0)alkyl, (C6-Ci0)aryl, ( -
Cio)aralkyl, (Ci-Cio)heterocyclyl, (Ci-Cio)heterocyclyl(Ci-Cio)alkyl, (Ci-Cio)heteroaryl, and
(Ci-Cio)heteroaryl(Ci-Cio)alkyl; and wherein A is the hydrolytically deprotectable masked
primary amine.
47. The hollow hydrogel capsule of claim 46, wherein R and R4 are H.
48. The hollow hydrogel capsule of claim 46, wherein R2, R3, and R4 are H.
49. The hollow hydrogel capsule of claim 46, wherein L1 is selected from the group
consisting of O, C(O), NH, C(0)0, OC(O), OC(0)0, C(0)NH, OC(0)NH, NHC(O),
NHC(0)NH, (Ci-C3o)alkylene, and (Ci-C3o)haloalkylene, wherein each alkylene and
haloalkylene is independently unsubstituted or further substituted with at least one J .
50. The hollow hydrogel capsule of claim 46, where L1 is a covalent bond between the vinyl
group and the masked primary amine.
51. The hollow hydrogel capsule of claim 34, wherein the vinyl amine comprising the
masked primary amine is N-vinyl formamide,
52. The hollow hydrogel capsule of claim 34, wherein the polyvinyl compound includes
hydrolyzable bonds that are at least partially hydrolyzed in the hydrogel shell.
53. The hollow hydrogel capsule of claim 34, wherein the polyvinyl compond has two vinyl
groups.
54. The hollow hydrogel capsule of claim 34, wherein the polyvinyl compound has the
following structure
wherein each of R5, R6, and R7 are independently at each occurrence selected from the
group consisting of hydrogen, F, CI, Br, I, CN, CF3, OCF3, (Ci-Cio)alkoxy, and (Ci-Cio)alkyl;
wherein L is independently at each occurrence selected from the group consisting of a
bond, O, S, C(O), S(O), methylenedioxy, ethylenedioxy, NR', SR' 2, S0 2R', S0 2NR', S0 3,
C(0)C(0), C(0)CH 2C(0), C(S), C(0)0, OC(O), OC(0)0, C(0)NR', OC(0)NR', C(S)NR',
(CH2)o-2NHC(0), N(R')N(R')C(0), N(R')N(R')C(0)0, N(R')N(R')C(0)NR', N(R')S0 2,
N(R')S0 2NR', N(R')C(0)0, N(R')C(0), N(R')C(S), N(R')C(0)NR', N(R')C(S)NR',
N(C(0)R')C(0), N(OR'), C(=NH)NR', C(0)N(OR'), and C(=NOR'); wherein L3 is
independently at each occurrence selected from the group consisting of (Ci-C3o)alkylene, (Ci-
C30)haloalkylene, (Co-C3o)alkyl(C4-C3o)cycloalkyl(Co-C3o)alkylene, (C0-C30)alkyl(CiC
3o)heterocyclyl(Co-C3o)alkylene, (Co-C3o)alkyl(C6-C3o)aryl(C0-C3o)alkylene, and (C0-
C3o)alkyl(Ci-C3o)heteroaryl(Co-C3o)alkylene, wherein each alkylene, haloalkylene,
cycloalkylene, arylene, heterocyclylene, and heteroarylene is independently unsubstituted or
further substituted with at least one J';
wherein the variable J' independently at each occurrence is selected from the group
consisting of F, CI, Br, I, OR', CN, CF3, OCF3, R', O, S, C(O), S(O), methylenedioxy,
ethylenedioxy, N(R') 2, SR', S(0)R', S0 2R', S0 2N(R') 2, S0 3R', C(0)R', C(0)C(0)R',
C(0)CH 2C(0)R', C(S)R', C(0)OR', OC(0)R', OC(0)OR', C(0)N(R') 2, OC(0)N(R') 2,
C(S)N(R') 2, (CH2)o-2NHC(0)R', N(R')N(R')C(0)R', N(R')N(R')C(0)OR',
N(R')N(R')C(0)N(R') 2, N(R')S0 2R', N(R')S0 2N(R') 2, N(R')C(0)OR', N(R')C(0)R',
N(R')C(S)R', N(R')C(0)N(R') 2, N(R')C(S)N(R') 2, N(C(0)R')C(0)R', N(OR')R',
C(=NH)N(R') 2, C(0)N(OR')R', and C(=NOR')R'; and
wherein R' is independently at each occurrence is selected from the group consisting of
hydrogen, (Ci-Cio)alkyl, (C4-Ci0)cycloalkyl, (C4-Ci0)cycloalkyl(Ci-Ci 0)alkyl, (C6-Ci0)aryl, ( -
Cio)aralkyl, (Ci-Cio)heterocyclyl, (Ci-Cio)heterocyclyl(Ci-Cio)alkyl, (Ci-Cio)heteroaryl, and
(Ci-Cio)heteroaryl(Ci-Cio)alkyl, wherein each alkyl, cycloalkyl, cycloalkylalkyl, aryl, aralkyl,
heterocyclyl, heterocyclylalkyl, heteroaryl, and heteroarylalkyl is independently unsubstituted or
substituted with 1-3 J'.
55. The hollow hydrogel capsule of claim 54, wherein each of R6 and R7 are hydrogen.
56. The hollow hydrogel capsule of claim 54, wherein each of R5, R6, and R7 are hydrogen.
57. The hollow hydrogel capsule of claim 54, wherein L is independently at each occurrence
selected from the group consisting of a bond, O, S, C(O), S(O), methylenedioxy, ethylenedioxy,
NH, SH2, S0 2H, S0 2NH, S0 3, C(0)C(0), C(0)CH 2C(0), C(S), C(0)0, OC(O), OC(0)0,
C(0)NH, OC(0)NH, C(S)NH, (CH2)0-2NHC(O), NHNHC(O), NHNHC(0)0, NHNHC(0)NH,
N(R')S0 2, NHS0 2NH, NHC(0)0, NHC(O), NHC(S), NHC(0)NH, NHC(S)NH,
N(C(0)H)C(0), N(OH), C(=NH)NH, C(0)N(OH), and C(=NOH).
58. The hollow hydrogel capsule of claim 54, wherein L is independently at each occurrence
selected from the group consisting of O, C(O), NH, C(0)0, OC(O), OC(0)0, C(0)NH,
OC(0)NH, NHC(0)0, NHC(O), and NHC(0)NH.
59. The hollow hydrogel capsule of claim 54, wherein L is -C(0)NH-, wherein the C(O)
group is bound directly to the vinyl group.
60. The hollow hydrogel capsule of claim 54, wherein L is independently at each occurrence
selected from the group consisting of (Ci-Cio)alkylene, (Ci-Cio)haloalkylene, (Co-Cio)alkyl(C4-
Cio)cycloalkyl(C0-Cio)alkyl, (Co-Cio)alkyl(Ci-C3o)heterocyclyl(Co-Cio)alkyl, (C0-Cio)alkyl(C6-
C3o)aryl(Co-Cio)alkyl, and (Ci-C3o)heteroaryl(Co-C3o)alkyl, wherein each alkyl, haloalkyl,
cycloalkyl, aryl, heterocyclyl, and heteroaryl is independently unsubstituted or further substituted
with at least one J'.
61. The hollow hydrogel capsule of claim 54, wherein L is independently at each occurrence
selected from the group consisting of (Ci-Cio)alkylene and (Ci-Cio)haloalkylene.
62. The hollow hydrogel capsule of claim 54, wherein L is -CH2-
63. The hollow hydrogel capsule of claim 34, wherein the polyvinyl molecule is N,N'
methylenebis(acrylamide)
64. The hollow hydrogel capsule of claim 34, wherein the at least one molecule comprising a
plurality of functional groups condensable with primary amines has two functional groups
condensable with primary amines.
65. The hollow hydrogel capsule of claim 34, wherein the at least one molecule comprising a
plurality of functional groups condensable with primary amines has the following structure
D L4 D
wherein L4 is independently at each occurrence selected from the group consisting of (Ci-
C3o)alkylene, (Ci-C3o)haloalkylene, (Co-C3o)alkyl(C4-C3o)cycloalkyl(Co-C3o)alkylene, (C0-
C3o)alkyl(Ci-C3o)heterocyclyl(Co-C3o)alkylene, (Co-C3o)alkyl(C6-C3o)aryl(Co-C3o)alkylene, and
(Co-C3o)alkyl(Ci-C3o)heteroaryl(Co-C3o)alkylene, wherein each alkylene, haloalkylene,
cycloalkylene, arylene, heterocyclylene, and heteroarylene is independently unsubstituted or
further substituted with at least one J";
wherein D is independently at each occurrence selected from the group consisting of CN,
O, S, C(O), S(O), SR", S(0)R", S0 2R", S0 2N(R") 2, S0 3R", C(0)R", C(0)C(0)R",
C(0)CH 2C(0)R", C(S)R", C(0)OR", OC(0)R", OC(0)OR", C(0)N(R") 2, OC(0)N(R") 2,
C(S)N(R") 2, N(R")C(0)OR", N(R")C(S)R", N(R")C(0)N(R") 2, N(R")C(S)N(R") 2,
C(=NH)N(R") 2, C(0)N(OR")R", and C(=NOR");
wherein J" is independently at each occurrence selected from the group consisting of F,
CI, Br, I, OR", CN, CF3, OCF3, R", O, S, C(O), S(O), methylenedioxy, ethylenedioxy, N(R") 2,
SR", S(0)R", S0 2R", S0 2N(R") 2, S0 3R", C(0)R", C(0)C(0)R", C(0)CH 2C(0)R",
C(S)R", C(0)OR", OC(0)R", OC(0)OR", C(0)N(R") 2, OC(0)N(R") 2, C(S)N(R") 2, (CH2)o-
2NHC(0)R", N(R")N(R")C(0)R", N(R")N(R")C(0)OR", N(R")N(R")C(0)N(R") 2,
N(R")S0 2R", N(R")S0 2N(R") 2, N(R")C(0)OR", N(R")C(0)R", N(R")C(S)R",
N(R")C(0)N(R") 2, N(R")C(S)N(R") 2, N(C(0)R")C(0)R", N(OR")R", C(=NH)N(R") 2,
C(0)N(OR")R", and C(=NOR")R"; and
wherein R" is independently at each occurrence selected from the group consisting of
hydrogen, (Ci-Cio)alkyl, (C4-Ci0)cycloalkyl, (C4-Ci0)cycloalkyl(Ci-Ci 0)alkyl, (C6-Ci0)aryl, ( -
Cio)aralkyl, (Ci-Cio)heterocyclyl, (Ci-Cio)heterocyclyl(Ci-Cio)alkyl, (Ci-Cio)heteroaryl, and
(Ci-Cio)heteroaryl(Ci-Cio)alkyl, wherein each alkyl, cycloalkyl, cycloalkylalkyl, aryl, aralkyl,
heterocyclyl, heterocyclylalkyl, heteroaryl, and heteroarylalkyl is independently unsubstituted or
substituted with 1-3 J".
66. The hollow hydrogel capsule of claim 65, wherein D is independently at each occurrence
selected from the group consisting of O, C(O), S(0)H, S0 2H, S0 3H, C(0)H, C(0)C(0)H,
C(0)CH 2C(0)H, C(S)H, C(0)OH, OC(0)H, OC(0)OH, N(R")C(0)OH, N(R")C(S)H, and
C(=NOH)H.
67. The hollow hydrogel capsule of claim 65, wherein D is -C(0)H.
68. The hollow hydrogel capsule of claim 65, wherein L4 is (Ci-Cio)alkylene independently
unsubstituted or further substituted with at least one J".
69. The hollow hydrogel capsule of claim 65, wherein L4 is propylene, -CH2-CH2-CH2- .
70. The hollow hydrogel capsule of claim 34, wherein the at least one molecule comprising a
plurality of functional groups c glutaraldehyde,
71. The hollow hydrogel capsule of claim 34, wherein the polymerized composition is a
dispersion polymerized composition.
72. The hollow hydrogel capsule of claim 34, wherein the polymerized composition is a freeradical
polymerized composition.
73. The hollow hydrogel capsule of claim 34, wherein the shell comprises a plurality of
primary amine groups.
74. The hollow hydrogel capsule of claim 34, wherein the diameter of the capsule is about
0.01 mhi - 100 mhi.
75. The hollow hydrogel capsule of claim 34, wherein the diameter of the capsule is about
0.1 mih - 20 mih.
76. The hollow hydrogel capsule of claim 34, wherein the capsule is substantially spherical.
77. The hollow hydrogel capsule of claim 34, wherein the shell has a thickness of about
0.001 mh - 20 mhi.
78. The hollow hydrogel capsule of claim 34, wherein the shell has a thickness of about 0.01
mih - 10 mih.
79. The hollow hydrogel capsule of claim 34, wherein the shell is porous.
80. The hollow hydrogel capsule of claim 79, wherein the shell has a pore size of about
0.0001 nm - 100 nm.
81. The hollow hydrogel capsule of claim 79, wherein the shell has a pore size of about 1 nm
- 40 nm.
82. The hollow hydrogel capsule of claim 34, wherein the hydrogel shell comprises metal
nanoparticles.
83. The hollow hydrogel capsule of claim 82, wherein the metal nanoparticles comprise gold.
84. The hollow hydrogel capsule of claim 82, wherein the metal nanoparticles are a) within
the hydrogel shell, b) on the outer surface of the hydrogel shell, or c) a combination thereof.
85. The hollow hydrogel capsule of claim 82, wherein the hydrogel shell comprises about 1-
100,000 nanoparticles.
86. The hollow hydrogel capsule of claim 82, wherein the hydrogel shell comprises about 10-
10,000 nanoparticles.
87. The hollow hydrogel capsule of claim 82, wherein the average diameter of the
nanoparticles is about 0.01 nm- 100 nm.
88. The hollow hydrogel capsule of claim 82, wherein the diameter of the nanoparticles is
about 0.1 nm - 50 nm.
89. The hollow hydrogel capsule of claim 34, further comprising at least one molecule that
has at least one of reacted with or formed an electrostatic bond with a primary amine group on
the shell, such that the molecule limits the permeability of the hollow hydrogel capsule.
90. The hollow hydrogel capsule of claim 89,
wherein the at least one molecule that has reacted with or formed an electrostatic bond
with the primary amine group on the shell is an organic compound that comprises at least one
functional group selected from the group consisting of CN, O, S, C(O), S(O), SR"\ S(0)R"',
S0 2R'", S0 2N(R"') 2, SO3R'", C(0)R"', C(0)C(0)R"', C(0)CH 2C(0)R"', C(S)R"',
C(0)OR"', OC(0)R"', OC(0)OR"', C(0)N(R"') 2, OC(0)N(R"') 2, C(S)N(R"') 2,
N(R"')C(0)OR"', N(R"')C(S)R"', N(R"')C(0)N(R"') 2, N(R"')C(S)N(R"') 2,
C(=NH)N(R"') 2, C(0)N(OR"')R"', and C(=NOR"');
wherein R"' is independently at each occurrence selected from the group consisting of
hydrogen, (Ci-Cio)alkyl, (C4-Ci0)cycloalkyl, (C4-Ci0)cycloalkyl(Ci-Ci 0)alkyl, (C6-Ci0)aryl, ( -
Cio)aralkyl, (Ci-Cio)heterocyclyl, (Ci-Cio)heterocyclyl(Ci-Cio)alkyl, (Ci-Cio)heteroaryl, and
(Ci-Cio)heteroaryl(Ci-Cio)alkyl, wherein each alkyl, cycloalkyl, cycloalkylalkyl, aryl, aralkyl,
heterocyclyl, heterocyclylalkyl, heteroaryl, and heteroarylalkyl is independently unsubstituted or
substituted with 1-3 J"'; and
wherein J"' is independently at each occurrence selected from the group consisting of F,
CI, Br, I, OR'", CN, CF3, OCF3, R" O, S, C(O), S(O), methylenedioxy, ethylenedioxy,
N(R"') 2, SR"\ S(0)R"', S0 2R"', S0 2N(R"') 2, S0 3R"', C(0)R"', C(0)C(0)R"',
C(0)CH 2C(0)R'", C(S)R"', C(0)OR"', OC(0)R"', OC(0)OR"', C(0)N(R"') 2,
OC(0)N(R"') 2, C(S)N(R"') 2, (CH2)o-2NHC(0)R"', N(R"')N(R"')C(0)R"',
N(R"')N(R"')C(0)OR"', N(R"')N(R"')C(0)N(R"') 2, N(R"')S0 2R"', N(R"')S0 2N(R"') 2,
N(R"')C(0)OR"', N(R"')C(0)R"', N(R"')C(S)R"', N(R"')C(0)N(R"') 2,
N(R"')C(S)N(R"') 2, N(C(0)R"')C(0)R"', N(OR"')R"', C(=NH)N(R"') 2,
C(0)N(OR"')R"', and C(=NOR"')R"'.
91. The hollow hydrogel capsule of claim 90, wherein the at least one molecule that has
reacted with or formed an electrostatic bond with the primary amine group on the shell is an
organic compound that comprises at least one functional group selected from the group
consisting of O, C(O), S(0)H, S0 2H, S0 3H, C(0)H, C(0)C(0)H, C(0)CH 2C(0)H, C(S)H,
C(0)OH, OC(0)H, OC(0)OH, N(R")C(0)OH, N(R")C(S)H, and C(=NOH)H.
92. The hollow hydrogel capsule of claim 90, wherein the at least one molecule that has
reacted with or formed an electrostatic bond with the primary amine group on the shell is a
polymeric carboxylic-acid-containing molecule, wherein the reaction with the primary amine
group comprises a condensation between a carboxylic acid group on the polymeric carboxylicacid-
containing molecule and the primary amine group.
93. The hollow hydrogel capsule of claim 90, wherein the organic compound is a (C2-
C6oo,ooo)hydrocarbyl group.
94. The hollow hydrogel capsule of claim 89, wherein the at least one molecule that has
reacted with the primary amine group on the shell is hyaluronic acid.
95. The hollow hydrogel capsule of claim 34, wherein prior to hydrolysis and crosslinking
the polymerized composition comprises particles.
96. A hydrogel capsule composition for treatment of a subterranean formation comprising:
at least one hollow hydrogel capsule of claim 34 and
a downhole composition for subterranean petroleum or water well drilling, stimulation,
clean-up, production, completion, abandonment, or a combination thereof.
97. The hydrogel capsule composition of claim 96, wherein the downhole composition for
subterranean petroleum or water well drilling, stimulation, clean-up, production, completion,
abandonment, or a combination thereof comprises a drilling fluid, stimulation fluid, fracking
fluid, spotting fluid, clean-up fluid, production fluid, completion fluid, remedial treatment fluid,
abandonment fluid, pill, acidizing fluid, cementing fluid, or a combination thereof.
98. A method of making the hollow hydrogel capsule of claim 34, comprising:
polymerizing the pre-polymerized composition comprising the at least one vinyl amine
comprising the hydro lytically deprotectable masked primary amine, and the at least one
polyvinyl compound, to give a first polymer;
hydro lyzing the first polymer, to deprotect at least some of the masked primary amines,
giving a second polymer;
cross-linking the second polymer with the at least one molecule comprising the plurality
of functional groups condensable with primary amines, to give the hydrogel shell comprising the
hydrolyzed and crosslinked polymerized composition.
99. The method of claim 98, wherein the method is a template-free method.
100. The method of claim 98, wherein the hydrolyzing of the first polymer and the crosslinking
of the second polymer are carried out in- situ, sequentially, simultaneously, or a
combination thereof.
101. The method of claim 98, further comprising reacting the hydrogel capsule with a
permeability modifier, to give a hydrogel capsule with modified permeability of the hydrogel
shell.
102. The method of claim 101, wherein the permeability of the hydrogel shell is modified after
loading at least one cargo into the hollow interior of the hydrogel capsule.
103. The method of claim 98, further comprising forming metal nanoparticles at least one of
one and in the hydrogel shell.
104. The method of claim 98, further comprising loading at least one cargo into the hollow
interior of the hydrogel capsule.
105. The method of claim 98, further comprising diffusing at least one cargo into the hollow
interior of the hydrogel capsule.