Technical Field
The present invention relates to the process of producing (poly)ol block copolymers with
5 > 70% primary hydroxyl end groups. The process can be a two step process generally
carried out in two separate reactions. The invention also relates to products and
compositions incorporating such copolymers or their residues.
Background
1 o It is generally desirable for polyols that are used in polyurethane applications to have
primary hydroxyl end groups, due to the increased reactivity of these primary hydroxyl
groups with isocyanates (compared to less reactive secondary hydroxyls). Polyether
polyols are generally produced by either basic catalysis using sodium or potassium
hydroxide or by using so-called double metal cyanide (DMC) catalysts. Advantageously,
15 hydroxide catalysts are able to react with both ethylene oxide (EO) and propylene oxide
(PO) and can be used to end-cap PO based polyols with EO, resulting in polyols with all
primary hydroxyl end groups. Unfortunately, the hydroxide catalyst process includes a
lengthy purification including neutralisation, filtration and drying. Furthermore, alkaline
catalysts promote formation of unsaturated, non-hydroxyl end groups at higher molecular
20 weights, resulting in reduced functionality of the polyols and poor quality polyurethanes.
DMC catalysts produce polyols with very low amounts of unsaturated end groups even
at higher molecular weights and do not require any purification. However, DMC catalysts
are less reactive with EO than PO and do not effectively end-cap PO polyols with EO to
generate polyols with 100% primary hydroxyl end groups. Instead, the EO mostly reacts
25 into long polyethylene oxide chains leaving the PO polyol with a high molecular weight
component (which results in poor quality polyurethane products) and mostly less reactive
secondary hydroxyl end groups.
In order to produce polyols above -2000 molecular weight (Mn) with low unsaturation,
the desired functionality and a high proportion of primary hydroxyl end groups it is has
30 been necessary to produce a primarily PO based polyol using a DMC catalyst and then
end-cap this with EO using hydroxide catalysts entailing a complex purification process.
This is both inefficient and expensive.
Various methods, such as those disclosed in W02001 044347 and W020041111 07,
have been suggested to increase the proportion of primary hydroxyl end groups using
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DMC catalysts. This generally involves starting with a predominantly PO feed and
increasing the ratio of EO in the feed as the reaction continues. Primary hydroxyl
contents of around 40-60% have been demonstrated by this method.
It also known that DMC catalysts can be used with epoxides and carbon dioxide to
5 produce so called 'polyether carbonate' polyols. Various methods include those
disclosed in W02008058913, W02008013731 and US6762278. Typically, these
processes require high pressures to enable even moderate C02 content within the
polyols. These polyols have primarily been demonstrated with PO and hence have a very
low (<5%) primary hydroxyl content.
10 US10174151 discloses a method for making a polyether carbonate polyol using a DMC
where a polyol is first made with C02 and PO and then end-capped with increasing ratios
of EO/PO with a DMC in a solvent (cyclic propylene or ethylene carbonate). The
maximum primary hydroxyl content demonstrated by this method is 65%.
W02015059068 and US2015/0259475 from Covestro disclose the use of a DMC
15 catalyst for the production of polyether carbonate polyols from C02 and alkylene oxide
in the presence of a starter compound. Many H-functional starter compounds are listed
including polyether carbonate polyols, polycarbonate polyols and polycarbonates.
A DMC catalyst requires a pre-activation step, usually in the absence of C02, which
initially produces a polyether. C02 is then added and incorporated into the polymer
20 structure. This means that a DMC catalyst alone cannot produce low molecular weight
polyols (e.g. <1 000 Mn) with substantial C02 content and the C02 content of the polyol
is even restricted at higher weights such as 2000 Mn. Polyethercarbonate polyols
produced by a DMC alone generally have a structure which is rich in ether linkages in
the centre of the polymer chain and richer in carbonate groups towards the hydroxyl
25 terminal groups. This is not advantageous as the ether groups are substantially more
stable to heat and basic conditions than the carbonate linkages.
W02010062703 discloses production of block copolymers having a polycarbonate block
and a hydrophilic block (e.g. a polyether). Various structures are described generally with
a polyether block having polycarbonate blocks at either end. Some examples include a
30 polycarbonate block with polyether end blocks. A two pot production is described, using
in some examples a carbonate catalyst in the first reaction to produce an alternating
polycarbonate block, followed by quenching of the reaction, isolation of the polyol from
solvents and unreacted monomers and then a second batch reaction with a DMC catalyst
(in the absence of C02) to incorporate the hydrophilic oligomer, such as poly(alkylene
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oxide). Some examples use ethylene oxide as the ether block, but no determination is
made of the proportion of primary and secondary hydroxyl end groups. The polymers
have use in enhanced oil recovery.
It has been advantageously found that by using polycarbonate starters and a DMC
5 catalyst with epoxides and optionally C02, (poly)ols can be produced with very high
primary hydroxyl content (greater than 70%, even greater than 80% primary hydroxyl
end groups). The use of the carbonate starters (either directly from a first reaction mixture
or using purified starters materials) is advantageous in promoting even end-capping with
a DMC catalyst in absence of C02.
1 o The (poly)ols can be made with varying C02 contents, low degrees of unsaturation, high
primary hydroxyl content and don't require the purification processes used for hydroxide
catalysts. The process is therefore advantageous over metal hydroxide catalysts, DMC
catalysts (alone) and in enabling the use of C02 to make (poly)ols with reduced carbon
footprint.
15 Advantageously, the low molecular weight polycarbonate (poly)ol starters do not have to
be isolated but can be made in one reactor and transferred directly into the second
without removing any catalyst, unreacted monomer or solvents.
Furthermore, the invention can be used to produce polycarbonate block polyether
(poly)ol block copolymers which contain a core of high carbonate content chains with a
20 terminal block of polyether chains. Polyurethanes made from such polyols benefit from
the advantages of high carbonate linkages (e.g. increased strength, increased chemical
resistance, resistance to both hydrolysis and oil etc) whilst still retaining the higher
thermal stability that ether end blocks provide. The (poly)ols can advantageously be
made using the same or similar epoxide reactants in both reactions.
25
Summary of the Invention
According to the first aspect of the invention, there is provided a process for producing a
(poly)ol block copolymer comprising the reaction of a DMC catalyst with a polycarbonate
or polyester (poly)ol (co)polymer and ethylene oxide and optionally one or more other
30 alkylene oxides to produce a (poly)ol block copolymer wherein > 70% of the copolymer
chain ends are terminated by primary hydroxyl groups.
According to the second aspect of the present invention, there is also provided a process
for producing a (poly)ol block copolymer comprising a first reaction in a first reactor and
a second reaction in a second reactor; wherein the first reaction is the reaction of a
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carbonate catalyst with C02 and alkylene oxide, in the presence of a starter and
optionally a solvent to produce a polycarbonate copolymer and the second reaction is
the reaction of a DMC catalyst with the polycarbonate copolymer of the first reaction,
ethylene oxide and optionally one or more other alkylene oxides to produce a (poly)ol
5 block copolymer, wherein > 70% of the copolymer chain ends are terminated by primary
hydroxyl groups.
Typically, the polycarbonate or polyester (poly)ol (co)polymer is added to pre-activated
DMC catalyst.
The polycarbonate or polyester (poly)ol (co)polymer may be added to the DMC catalyst
1 o continuously or semi-continuously. Preferably, the polycarbonate or polyester (poly)ol
(co)polymer is added continuously. By semi-continuously is meant that the
polycarbonate or polyester (poly)ol is added in at least two portions, wherein at least one
portion is added after the start of the reaction. Preferably, the polycarbonate or polyester
(poly)ol is added in several portions.
15 Typically, at least a portion of the polycarbonate or polyester (poly)ol (co)polymer is
added after the start of the reaction.
Typically, the DMC catalyst is pre-activated with a starter compound, or the
polycarbonate or polyester (poly)ol (co)polymer, or with the (poly)ol block copolymer
product.
20 Preferably, > 75%, more preferably, >80% of the copolymer chain ends are terminated
by primary hydroxyl groups.
Preferably, the polymer chains are evenly end-capped. By evenly end-capped is meant
that on average more than 75% of the polymer chains are end capped with an EO
residue, more typically, more than 85% of the polymer chains are end capped with an
25 EO residue, most typically, at least 90% of the polymer chains are end capped with an
EO residue.
When referring to "first reaction" herein is meant the first reaction according to the second
aspect of the present invention.
It is also possible to add the components in separate reactions and reactors.
30 Advantageously, by this it means it is possible to increase activity of the catalysts and
this can lead to a more efficient process, compared with a process in which all of the
materials are provided at the start of one reaction. Large amounts of some of the
components present throughout the reaction may reduce efficiency of the catalysts.
Reacting this material in separate reactors can be used to prevent this reduced efficiency
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of the catalysts and/or can be used to optimise catalyst activity. The reaction conditions
of each reactor can be tailored to optimise the reactions for each catalyst.
Additionally, not loading the total amount of each component at the start of the reaction
and having the catalyst for the first reaction in a separate reactor to the catalyst for the
5 second reaction, can provide more even catalysis, and more uniform polymer products.
In addition, polymers having a narrower molecular weight distribution, desired ratio and
distribution along the chain of ether to carbonate linkages, and/or improved (poly)ol
stability are possible.
Typically, the polycarbonate or polyester (poly)ol (co)polymer may be fed into the
1 o reaction with the DMC catalyst continuously or semi-continuously as a crude reaction
mixture, wherein said reactor or second reactor contains a pre-activated DMC catalyst.
This is advantageous as the polycarbonate (poly)ol can decompose if exposed to the
high temperatures used during DMC activation. Adding the (poly)ol after DMC activation
enables efficient formation of the block copolymer (poly)ol without significant degradation
15 to cyclic carbonate by-products.
Optionally, the crude reaction mixture fed into the reactor or second reactor may include
an amount of unreacted ethylene oxide and/or other alkylene oxide and/or starter, and
preferably no C02 .
The crude reaction mixture may be added at any suitable rate for the scale of the second
20 reaction, the reactivity of the catalyst in the second reaction and/or to control the
dispersity of the final product.
The polycarbonate or polyester (poly)ol (co)polymer is added in a continuous or semicontinuous
manner. Preferably, the polycarbonate or polyester (poly)ol (co)polymer is
25 added to the reaction with the DMC catalyst continuously. This allows controlled addition
of polycarbonate/polyester starter so that the optimum number of ethylene oxide
residues can be polymerised on to both ends of the growing polymer chain to an
advantageous length. Accordingly, this provides a (poly)ol block copolymer which is
evenly end capped.
30 The alkylene oxides may be selected from cyclohexene oxide, styrene oxide, ethylene
oxide, propylene oxide, butylene oxide, substituted cyclohexene oxides (such as
limonene oxide, C10H160 or 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, C11 H220),
alkylene oxides (such as ethylene oxide and substituted ethylene oxides), unsubstituted
or substituted oxiranes (such as oxirane, epichlorohydrin, 2-(2-methoxyethoxy)methyl
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oxirane (MEMO), 2-(2-(2-methoxyethoxy)ethoxy)methyl oxirane (ME2MO), 2-(2-(2-(2-
methoxyethoxy)ethoxy)ethoxy)methyl oxirane (ME3MO), 1 ,2-epoxybutane, glycidyl
ethers, glycidyl ester, glycidyl carbonates, vinyl-cyclohexene oxide, 3-phenyl-1 ,2-
epoxypropane, 2,3-epoxybutane, isobutylene oxide, cyclopentene oxide, 2,3-epoxy-
5 1 ,2,3,4-tetrahydronaphthalene, indene oxide, and functionalized 3,5-dioxaepoxides,
preferably propylene oxide.
When one or more other alkylene oxides are added to the reaction according to the first
aspect or the second reaction of the second aspect in addition to ethylene oxide, the
ethylene oxide addition may be increased mol/mol relative to the other alkylene oxide(s)
1 o at the end part of the reaction. Advantageously, this provides primary hydroxyl end
capping of the (poly)ol.
The reaction according to the first aspect of the present invention is carried out
substantially in the absence of C02.
With regard to the second aspect of the present invention, although typically any residual
15 C02 from the first reaction may be removed from the crude reaction product of the first
reaction prior to commencement of the second reaction such that the second reaction is
carried out without C02, it will be appreciated that a small amount of C02 may be present
in the second reaction mixture as an unused reagent of the first reaction. Alternatively,
the pressure of unused C02 from the first reaction may be used to transfer the first
20 reaction mixture into the second reactor for the second reaction, resulting in some initial
pressure from C02 in reactor 2, however no further C02 is added to reaction 2.
Typically the first reaction mixture contains less than 5% C02 by weight of the reaction
mixture prior to addition to the second reaction, preferably less than 2.5%, such as less
than 1.0%, less than 0.5% or less than 0.1 %. Typically, the second reaction is carried
25 out without the independent addition of C02. The polyether block produced in the second
reaction may have less than 1% carbonate linkages, preferably less than 0.5% carbonate
linkages, more preferably less than 0.1% carbonate linkages. Preferably the polyether
block produced in the second reaction is substantially free from carbonate
linkages.Typically, therefore the second reaction is carried out substantially in the
30 absence of C02.
Accordingly, by substantially in the absence of C02 is meant that the reaction is carried
out in the presence of less than 4 wt.% C02 by weight, preferably less than 2 wt. %, such
as less than 1.0 wt. %, less than 0.5 wt.% or less than 0.1 wt.% by weight of total
reactants, catalyst and products in the second reaction.
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Typically, ethylene oxide forms 5-100% mol/mol of the alkylene oxides added to the
reaction of the first aspect or second reaction of the second aspect of the invention, more
typically, 10-100%, most typically 10-50% mol/mol of the alkylene oxides added, and/or,
at least 5%, 10%, 15%, 20%, 25% or 30% mol/mol of the alkylene oxides added.
5 The alkylene oxide residues in the polycarbonate (poly)ol may be ethylene oxide and/or
propylene oxide residues and optionally, in addition, other epoxide residues.
Typically, at least 50% of the alkylene residues of the polycarbonate (poly)ol are ethylene
oxide or propylene oxide residues, more typically, at least 70% of the alkylene oxide
residues are ethylene oxide or propylene oxide residues, most typically, at least 90% of
1 o the alkylene oxide residues are ethylene oxide or propylene oxide residues, especially,
ethylene oxide at these levels.
The other alkylene oxide residues may be selected from cyclohexene oxide, styrene
oxide, ethylene oxide, propylene oxide, butylene oxide, substituted cyclohexene oxides
(such as limonene oxide, C10H160 or 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane,
15 C11 H220), alkylene oxides (such as ethylene oxide and substituted ethylene oxides),
unsubstituted or substituted oxiranes (such as oxirane, epichlorohydrin, 2-(2-
methoxyethoxy)methyl oxirane (MEMO), 2-(2-(2-methoxyethoxy)ethoxy)methyl oxirane
(ME2MO), 2-(2-(2-(2-methoxyethoxy)ethoxy)ethoxy)methyl oxirane (ME3MO), 1,2-
epoxybutane, glycidyl ethers, glycidyl esters, glycidyl carbonates, vinyl-cyclohexene
20 oxide, 3-phenyl-1 ,2-epoxypropane, 2,3-epoxybutane, isobutylene oxide, cyclopentene
oxide, 2,3-epoxy-1 ,2,3,4-tetrahydronaphthalene, indene oxide, and functionalized 3,5-
dioxaepoxides.
The ethylene oxide and/or optionally alkylene oxide and/or DMC may be added
continuously or semi-continuously to the reaction of the first aspect or the second reactor
25 according to the second aspect of the invention.
It will be appreciated that the second aspect of the present invention relates to a reaction
in which predominantly ether linkages are added to a growing polymer chain. Having
separate reactions allows the first reaction to proceed before a second stage in the
reaction. Mixing alkylene oxide, carbonate catalyst, starter compound and carbon
30 dioxide, may permit growth of a polymer having a high number of carbonate linkages.
Thereafter, adding the products to the DMC catalyst in the absence of C02 permits the
reaction to proceed by adding ether linkages to the growing polymer chain. Ether
linkages are more thermally stable than carbonate linkages and less prone to
degradation by bases such as the amine catalysts used in PU formation. Therefore,
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applications get the benefits of high carbonate linkages (such as increased strength,
chemical resistance, both oil and hydrolysis resistance etc) that are introduced from the
first reaction whilst retaining the stability of the (poly)ol through the ether linkages from
the product of the second reaction at the ends of the polymer chains.
5 Adding the components in the separate reactions and reactors may be useful to increase
activity of the catalysts and may lead to a more efficient process, compared with a
process in which all of the materials are provided at the start of one reaction. Large
amounts of some of the components present throughout the reaction may reduce
efficiency of the catalysts. Reacting this material in separate reactors may prevent this
1 o reduced efficiency of the catalysts and/or may optimise catalyst activity. The reaction
conditions of each reactor can be tailored to optimise the reactions for each catalyst.
Additionally, not loading the total amount of each component at the start of the reaction
and having the catalyst for the first reaction in a separate reactor to the catalyst for the
second reaction, may lead to even catalysis, and more uniform polymer products. This
15 in turn may lead to polymers having a narrower molecular weight distribution, desired
ratio and distribution along the chain of ether to carbonate linkages, and/or improved
(poly)ol stability.
The reaction temperature of the reaction according to the first aspect or the second
reaction of the second aspect may be in the range from about 50 to about 160°C,
20 preferably in the range from about 70 to about 140°C, more preferably from about 80 to
about 130°C.
The (poly)ol block copolymers of the present invention may be prepared from a suitable
alkylene oxide and carbon dioxide in the presence of a starter compound and a
carbonate catalyst for the first reaction; and then ethylene oxide, and optionally one or
25 more suitable alkylene oxides, in the presence of a double metal cyanide (DMC) catalyst
in the second reaction.
DMC catalysts are complicated compounds which comprise at least two metal centres
and cyanide ligands. The DMC catalyst may additionally comprise at least one of: one
or more complexing agents, water, a metal salt and/or an acid (e.g. in non-stoichiometric
30 amounts).
The first two of the at least two metal centres may be represented by M' and M".
M' may be selected from Zn(ll), Ru(ll), Ru(lll), Fe(ll), Ni(ll), Mn(ll), Co(ll), Sn(ll), Pb(ll),
Fe(lll), Mo(IV), Mo(VI), Al(lll), V(V), V(VI), Sr(ll), W(IV), W(VI), Cu(ll), and Cr(lll), M' is
optionally selected from Zn(ll), Fe(ll), Co(ll) and Ni(ll), optionally M' is Zn(ll).
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M" is selected from Fe(ll), Fe(lll), Co(ll), Co(lll), Cr(ll), Cr(lll), Mn(ll), Mn(lll), lr(lll), Ni(ll),
Rh(lll), Ru(ll), V(IV), and V(V), optionally M" is selected from Co(ll), Co(lll), Fe(ll), Fe(lll),
Cr(lll), lr(lll) and Ni(ll), optionally M" is selected from Co(ll) and Co(lll).
It will be appreciated that the above optional definitions for M' and M" may be combined.
5 For example, optionally M' may be selected from Zn(ll), Fe(ll), Co(ll) and Ni(ll), and M"
may optionally be selected from Co(ll), Co(lll), Fe(ll), Fe(lll), Cr(lll), lr(lll) and Ni(ll). For
example, M' may optionally be Zn(ll) and M" may optionally be selected from Co(ll) and
Co(lll).
If a further metal centre(s) is present, the further metal centre may be further selected
1 o from the definition of M' or M".
Examples of DMC catalysts which can be used in the process of the invention include
those described in US 3,427,256, US 5,536,883, US 6,291 ,388, US 6,486,361, US
6,608,231, us 7,008,900, us 5,482,908, us 5,780,584, us 5,783,513, us 5,158,922,
us 5,693,584, us 7,811 ,958, us 6,835,687, us 6,699,961, us 6,716,788, us
15 6,977,236, us 7,968,754, us 7,034,103, us 4,826,953, us 4,500 704, us 7,977,501,
US 9,315,622, EP-A-1568414, EP-A-1529566, and WO 2015/022290, the entire
contents of which, especially, insofar as they relate to DMC catalysts for the production
of the block copolymer as defined herein or reactions as defined herein, are incorporated
herein by reference.
20 It will be appreciated that the DMC catalyst may comprise:
M'd[M"e(CN)t]g
wherein M' and M" are as defined above, d, e, f and g are integers, and are chosen such
that the DMC catalyst has electroneutrality. Optionally, d is 3. Optionally, e is 1.
Optionally f is 6. Optionally g is 2. Optionally, M' is selected from Zn(ll), Fe(ll), Co(ll) and
25 Ni(ll), optionally M' is Zn(ll). Optionally M" is selected from Co(ll), Co(lll), Fe(ll), Fe(lll),
Cr(lll), lr(lll) and Ni(ll), optionally M" is Co(ll) or Co(lll).
It will be appreciated that any of these optional features may be combined, for example,
dis 3, e is 1, f is 6 and g is 2, M' is Zn(ll) and M" is Co(lll).
Suitable DMC catalysts of the above formula may include zinc hexacyanocobaltate(lll),
30 zinc hexacyanoferrate(lll), nickel hexacyanoferrate(ll), and cobalt
hexacyanocobaltate(lll).
There has been a lot of development in the field of DMC catalysts, and the skilled person
will appreciate that the DMC catalyst may comprise, in addition to the formula above,
further additives to enhance the activity of the catalyst. Thus, while the above formula
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may form the "core" of the DMC catalyst, the DMC catalyst may additionally comprise
stoichiometric or non-stoichiometric amounts of one or more additional components,
such as at least one complexing agent, an acid, a metal salt, and/or water.
For example, the DMC catalyst may have the following formula:
5 M'd[M"e(CN)t]g · hM"'X"i · jRc · kH20 · IHrX"'
wherein M', M", X"', d, e, f and g are as defined above. M"' can be M' and/or M". X" is
an anion selected from halide, oxide, hydroxide, sulphate, carbonate, cyanide, oxalate,
thiocyanate, isocyanate, isothiocyanate, carboxylate and nitrate, optionally X" is halide.
i is an integer of 1 or more, and the charge on the anion X" multiplied by i satisfies the
1 o valency of M"'. r is an integer that corresponds to the charge on the counterion X"'. For
example, when X"' is Cl-, r will be 1. I is 0, or a number between 0.1 and 5. Optionally, I
is between 0.15 and 1.5.
Rc is a complexing agent or a combination of one or more complexing agents. For
example, Rc may be a (poly)ether, a polyether carbonate, a polycarbonate, a
15 poly(tetramethylene ether diol), a ketone, an ester, an amide, an alcohol (e.g. a C1-s
alcohol), a urea and the like, such as propylene glycol, polypropylene glycol, (m)ethoxy
ethylene glycol, dimethoxyethane, tert-butyl alcohol, ethylene glycol monomethyl ether,
diglyme, triglyme, methanol, ethanol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol,
sec-butyl alcohol, 3-buten-1-ol, 2-methyl-3-buten-2-ol, 2-methyl-3-butyn-2-ol, 3-methyl-
20 1-pentyn-3-ol or a combination thereof, for example, Rc may be tert-butyl alcohol,
dimethoxyethane, or polypropylene glycol.
As indicated above, more than one complexing agent may be present in the DMC
catalysts used in the present invention. Optionally one of the complexing agents of Rc
may be a polymeric complexing agent. Optionally, Rc may be a combination of a
25 polymeric complexing agent and a non-polymeric complexing agent.. Optionally, a
combination of the complexing agents tert-butyl alcohol and polypropylene glycol may
be present.
It will be appreciated that if the water, complexing agent, acid and/or metal salt are not
present in the DMC catalyst, h, j, k and/or I will be zero respectively. If the water,
30 complexing agent, acid and/or metal salt are present, then h, j, k and/or I are a positive
number and may, for example, be between 0 and 20. For example, h may be between
0.1 and 4. j may be between 0.1 and 6. k may be between 0 and 20, e.g. between 0.1
and 10, such as between 0.1 and 5. I may be between 0.1 and 5, such as between 0.15
and 1.5.
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The polymeric complexing agent is optionally selected from a polyether, a polycarbonate
ether, and a polycarbonate. The polymeric complexing agent may be present in an
amount of from about 5% to about 80% by weight of the DMC catalyst, optionally in an
amount of from about 10% to about 70% by weight of the DMC catalyst, optionally in an
5 amount of from about 20% to about 50% by weight of the DMC catalyst.
The DMC catalyst, in addition to at least two metal centres and cyanide ligands, may
also comprise at least one of: one or more complexing agents, water, a metal salt and/or
an acid, optionally in non-stoichiometric amounts.
An exemplary DMC catalyst is of the formula Zn3[Co(CN)6]2 · hZnCI2 · kH20 ·
1 o j[(CH3)3COH], wherein h, k and j are as defined above. For example, h may be from 0 to
4 (e.g. from 0.1 to 4), k may be from 0 to 20 (e.g. from 0.1 to 1 0), and j may be from 0 to
6 (e.g. from 0.1 to 6).As set out above, DMC catalysts are complicated structures, and
thus, the above formulae including the additional components is not intended to be
limiting. Instead, the skilled person will appreciate that this definition is not exhaustive of
15 the DMC catalysts which are capable of being used in the invention.
The DMC catalyst may be pre-activated. Such pre-activation may be achieved by mixing
one or both catalysts with alkylene oxide (and optionally other components). Preactivation
of the DMC catalyst is useful as it enables safe control of the reaction
(preventing uncontrolled increase of unreacted monomer content) and removes
20 unpredictable activation periods. Optionally, the DMC catalyst may be pre-activated in
reactor 2 or separately. Optionally, the DMC catalyst may be pre-activated with a starter
compound or with the reaction product of the first or second reaction. When the DMC
catalyst is pre-activated with the reaction product of the first reaction, it may be preactivated
with some or all of the reaction product of the first reaction. The DMC catalyst
25 may be pre-activated with the (poly)ol block copolymer product which may be added into
the reactor, or may be the remaining product from a previous reaction, the so-called
'reaction heel'.
The starter compound which may be used in the processes for forming polycarbonate
ether (poly)ols may have the formula (Ill):
30 Z-t Rz)a (Ill)
Z can be any group which can have 1 or more -Rz groups attached to it, preferably 2 or
more -Rz groups attached to it. Thus, Z may be selected from optionally substituted
alkylene, alkenylene, alkynylene, heteroalkylene, heteroalkenylene, heteroalkynylene,
cycloalkylene, cycloalkenylene, hererocycloalkylene, heterocycloalkenylene, arylene,
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heteroarylene, or Z may be a combination of any of these groups, such as an
alkylarylene, heteroalkylarylene, heteroalkylheteroarylene or alkylheteroarylene group,
optionally Z is alkylene, heteroalkylene, arylene, or heteroarylene;
a is an integer which is at least 1, typically at least 2, optionally a is in the range of
5 between 1 or 2 and 8, optionally a is in the range of between 2 and 6; and
each Rz is independently selected from -OH, -NHR', -SH, -C(O)OH, PR'(O)(OH)2, -
P(O)(OR')(OH) or -PR'(O)OH, preferably Rz may be -OH, -C(O)OH or -NHR', more
preferably each Rz may be -OH, -C(O)OH or a combination thereof (e.g. each Rz
is -OH).
10 R' may be H, or optionally substituted alkyl, heteroalkyl, aryl, heteroaryl, cycloalkyl or
heterocycloalkyl, optionally R' is H or optionally substituted alkyl.
By using a starter compound in which a is an integer which is at least 2, a polycarbonate
polyol may be produced in the first step without any further processing of the reaction
product. In any case, the present invention allows the crude reaction product of the first
15 reaction to be added to the second reaction without further processing or isolation,
improving efficiency and allowing the reactions to be run as continuous reactions
improving both safety and controllability of the reaction conditions.
The starter compound which may be used in the processes for forming polycarbonate
(poly)ols of the present invention comprises at least one group, preferably at least two
20 groups, selected from a hydroxyl group (-OH), a thiol (-SH), an amine having at least one
N-H bond (-NHR'), a group having at least one P-OH bond (e.g.
-PR'(O)OH, PR'(O)(OH)2 or -P(O)(OR')(OH)), or a carboxylic acid group (-C(O)OH).
Where the starter is a polyfunctional starter compound, the starter compound comprises
at least two groups selected from a hydroxyl group (-OH), a thiol (-SH), an amine having
25 at least one N-H bond (-NHR'), a group having at least one P-OH bond (e.g. -PR'(O)OH,
PR'(O)(OH)2 or -P(O)(OR')(OH)), or a carboxylic acid group (-C(O)OH).
Z' corresponds to Rz, except that a bond replaces the labile hydrogen atom. Therefore,
the identity of each Z' depends on the definition of Rz in the starter compound. Thus, it
will be appreciated that each Z' may be -0-, -NR'-, -S-, -C(O)O-, -P(O)(OR')O-, -
30 PR'(0)(0-)2 or -PR'(O)O- (wherein R' may be H, or optionally substituted alkyl,
heteroalkyl, aryl, heteroaryl, cycloalkyl or heterocycloalkyl, preferably R' isH or optionally
substituted alkyl), preferably Z' may be -C(O)O-, -NR'- or -0-, more preferably each Z'
may be -0-, -C(O)O- or a combination thereof, more preferably each Z' may be -0-.
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More than one starter compound may be present in each reaction. The starter
compounds for the first and second reaction may be the same or different. Where there
are two different starter compounds, there may be two starter compounds in the second
reaction, wherein the starter compound in the first reaction is a first starter compound,
5 and wherein the second reaction comprises adding the first crude reaction mixture to the
second reactor comprising a second starter compound and double metal cyanide (OM C)
catalyst and, optionally, solvent and/or alkylene oxide. The second reaction of the
present invention may be conducted at least about 1 minutes after the first reaction,
optionally at least about 5 minutes, optionally at least about 15 minutes, optionally at
1 o least about 30 minutes, optionally at least about 1 hour, optionally at least about 2 hours,
optionally at least about 5 hours. It will be appreciated that in a continuous reaction these
periods are the average period from addition of monomer in the first reactor to transfer
of monomer residue into the second reactor.
The starter compound if polymeric may have a molecular weight (Mn) of at least about
15 200 Da or of at most about 1 000 Da.
For example, having a molecular weight of about 200 to 1000 Da, optionally about 300
to 700 Da, optionally about 400 Da.
The or each starter compound typically has one or more Rz groups, optionally two or
more, optionally three or more, optionally four or more, optionally five or more, optionally
20 six or more, optionally seven or more, optionally eight or more Rz groups, particularly
wherein Rz is hydroxyl.
It will be appreciated that any of the above features may be combined. For example, a
may be between 1 or 2 and 8, each Rz may be -OH, -C(O)OH or a combination thereof,
and Z may be selected from alkylene, heteroalkylene, arylene, or heteroarylene.
25 Exemplary starter compounds for either reaction include monofunctional starter
substances such as alcohols, phenols, amines, thiols and carboxylic acids; for example,
alcohols such as methanol, ethanol, 1- and 2-propanol, 1- and 2-butanol, linear or
branched C3-C2o-monoalcohol such as tert-butanol, 3-buten-1-ol, 3-butyn-1-ol, 2-methyl-
3-buten-2-ol, 2-methyl-3-butyn-2-ol, propargyl alcohol, 2-methyl-2-propanol, 1-tert-
30 butoxy-2-propanol, 1-pentanol, 2-pentanol, 3-pentanol, 1-hexanol, 2-hexanol, 3-hexanol,
1-heptanol, 2-heptanol, 3-heptanol, 1-octanol, 2-octanol, 3-octanol, 4-octanol, 1-
decanol, 1-dodecanol, phenol, 2-hydroxybiphenyl, 3-hydroxybiphenyl, 4-
hydroxybiphenyl, 2-hydroxypyridine, 3-hydroxypyridine, and 4-hydroxypyridine, monoethers
or esters of ethylene, propylene, polyethylene; polypropylene glycols such as
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ethylene glycol mono-methyl ether and propylene glycol mono-methyl ether, phenols
such as linear or branched C3-C2o alkyl substituted phenols, for example nonyl-phenols
or cetyl phenols monofunctional carboxylic acids such as formic acid, acetic acid,
propionic acid and butyric acid, fatty acids, such as stearic acid, palmitic acid, oleic acid,
5 linoleic acid, linolenic acid, benzoic acid and acrylic acid, and monofunctional thiols such
as ethanethiol, propane-1-thiol, propane-2-thiol, butane-1-thiol, 3-methylbutane-1-thiol,
2-butene-1-thiol, and thiophenol, or amines such as butylamine, tert-butylamine,
pentylamine, hexylamine, aniline, aziridine, pyrrolidine, piperidine, and morpholine;
and/or selected from diols such as 1 ,2-ethanediol (ethylene glycol), 1-2-propanediol, 1,3-
1 o propanediol (propylene glycol), 1 ,2-butanediol, 1-3-butanediol, 1 ,4-butanediol, 1,5-
pentanediol, 1 ,6-hexanediol, 1 ,8-octanediol, 1,1 0-decanediol, 1, 12-dodecanediol, 1,4-
cyclohexanediol, 1 ,2-diphenol, 1 ,3-diphenol, 1 ,4-diphenol, neopentyl glycol, catechol,
cyclohexenediol, 1 ,4-cyclohexanedimethanol, dipropylene glycol, diethylene glycol,
tripropylene glycol, triethylene glycol, tetraethylene glycol, polypropylene glycols (PPGs)
15 or polyethylene glycols (PEGs) having an Mn of up to about 1500g/mol, such as PPG
425, PPG 725, PPG 1000 and the like, triols such as glycerol, benzenetriol, 1 ,2,4-
butanetriol, 1 ,2,6-hexanetriol, tris(methylalcohol)propane, tris(methylalcohol)ethane,
tris(methylalcohol)nitropropane, trimethylol propane, polyethylene oxide triols,
polypropylene oxide triols and polyester triols, tetraols such as calix[4]arene, 2,2-
20 bis(methylalcohol)-1 ,3-propanediol, erythritol, pentaerythritol or polyalkylene glycols
(PEGs or PPGs) having 4-0H groups, polyols, such as sorbitol or polyalkylene glycols
(PEGs or PPGs) having 5 or more -OH groups, or compounds having mixed functional
groups including ethanolamine, diethanolamine, methyldiethanolamine, and
phenyldiethanolamine.
25 For example, the starter compound may be a monofunctional alcohol such as ethanol,
1-propanol, 2-propanol, 1-butanol, 2-butanol, 1-hexanol, 1-octanol, 1-decanol, 1-
dodecanol, a phenol such as nonyl-phenol or cetyl phenol or a mono-functional
carboxylic acid such as formic acid, acetic acid, propionic acid, butyric acid, fatty acids,
such as stearic acid, palmitic acid, oleic acid, linoleic acid, linolenic acid, benzoic acid,
30 acrylic acid.
For example, the starter compound may be a diol such as 1 ,2-ethanediol (ethylene
glycol), 1-2-propanediol, 1 ,3-propanediol (propylene glycol), 1 ,2-butanediol, 1-3-
butanediol, 1 ,4-butanediol, 1 ,5-pentanediol, 1 ,6-hexanediol, 1 ,8-octanediol, 1,10-
decanediol, 1, 12-dodecanediol, 1 ,4-cyclohexanediol, 1 ,2-diphenol, 1 ,3-diphenol, 1,4-
35 diphenol, neopentyl glycol, catechol, cyclohexenediol, 1 ,4-cyclohexanedimethanol,
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poly(caprolactone) diol, dipropylene glycol, diethylene glycol, tripropylene glycol,
triethylene glycol, tetraethylene glycol, polypropylene glycols (PPGs) or polyethylene
glycols (PEGs) having an Mn of up to about 1500g/mol, such as PPG 425, PPG 725,
PPG 1000 and the like. It will be appreciated that the starter compound may be 1,6-
5 hexanediol, 1 ,4-cyclohexanedi methanol, 1 , 12-dodecanediol, poly( caprolactone) diol,
PPG 425, PPG 725, or PPG 1000. Preferably the the starter compound may be a diol
such as 1 ,2-ethanediol (ethylene glycol), 1 ,3-propanediol (propylene glycol), 1,2-
butanediol, 1-3-butanediol, 1 ,4-butanediol, 1 ,5-pentanediol, 1 ,6-hexanediol, 1,8-
octanediol, 1,1 0-decanediol, 1, 12-dodecanediol, 1 ,4-cyclohexanediol, 1 ,2-diphenol, 1,3-
1 o diphenol, 1 ,4-diphenol, neopentyl glycol, catechol, cyclohexenediol, 1,4-
cyclohexanedimethanol, poly(caprolactone) diol, dipropylene glycol, diethylene glycol,
tripropylene glycol, triethylene glycol, tetraethylene glycol, polypropylene glycols (PPGs)
or polyethylene glycols (PEGs) having an Mn of up to about 1500g/mol, such as PPG
425, PPG 725, PPG 1000 and the like. It will be appreciated that the starter compound
15 may be 1 ,6-hexanediol, 1 ,4-cyclohexanedimethanol,
poly(caprolactone) diol, PPG 425, PPG 725, or PPG 1000.
1, 12-dodecanediol,
Further exemplary starter compounds may include diacids such as oxalic acid, malonic
acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid,
sebacic acid, undecanedioic acid, dodecanedioic acid or other compounds having mixed
20 functional groups such as lactic acid, glycolic acid, 3-hydroxypropanoic acid, 4-
hydroxybutanoic acid, 5-hydroxypentanoic acid.
The ratio of the starter compound, if present, to the carbonate catalyst may be in amounts
of from about 1000:1 to about 1:1, for example, from about 750:1 to about 5:1, such as
from about 500: 1 to about 1 0: 1, e.g. from about 250: 1 to about 20: 1, or from about 125: 1
25 to about 30:1, or from about 50:1 to about 20:1. These ratios are molar ratios. These
ratios are the ratios of the total amount of starter to the total amount of the carbonate
catalyst used in the processes. These ratios may be maintained during the course of
addition of materials.
By a crude reaction mixture is meant that the product of the reaction is typically not
30 isolated prior to addition of the reaction mixture ot the second reaction. Preferably, the
reaction mixture undergoes no further processing steps prior to its addition to the second
reaction.
The product of the first reaction may be a low molecular weight polycarbonate (poly)ol.
The preferred molecular weight (Mn) of the polycarbonate (poly)ol depends on the
35 preferred overall molecular weight of the (poly)ol block copolymer. The molecular weight
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(Mn) of the polycarbonate (poly)ol may be in the range from about 200 to about 4000
Da, from about 200 to about 2000 Da, from about 200 to about 1000 Da, or from about
400 to about 800 Da, as measured by Gel Permeation Chromatography.
The first reaction may produce a generally alternating polycarbonate (poly)ol product.
5 The product of the first reaction may be fed into the separate reactor containing a preactivated
DMC catalyst. The first product may be fed into the separate reactor as a crude
reaction mixture.

CLAIMS
1. A process for producing a (poly)ol block copolymer comprising the reaction of a
DMC catalyst with a polycarbonate or polyester (poly)ol (co)polymer and ethylene oxide
and optionally one or more other alkylene oxides to produce a (poly)5 ol block copolymer
wherein > 70% of the copolymer chain ends are terminated by primary hydroxyl groups.
2. A process for producing a (poly)ol block copolymer comprising a first reaction in
a first reactor and a second reaction in a second reactor; wherein the first reaction is the
reaction of a carbonate catalyst with CO2 and alkylene oxide, in the presence of a starter
10 and optionally a solvent to produce a polycarbonate (poly)ol copolymer and the second
reaction is the reaction of a DMC catalyst with the polycarbonate (poly)ol copolymer of
the first reaction, ethylene oxide and optionally one or more other alkylene oxides to
produce a (poly)ol block copolymer, wherein > 70% of the copolymer chain ends are
terminated by primary hydroxyl groups.
15 3. A process according to any preceding claim, wherein the polycarbonate or
polyester (poly)ol (co)polymer is fed into the reaction with the DMC catalyst continuously
or semi-continuously, as a crude reaction mixture, wherein said reaction contains a preactivated
DMC catalyst.
4. A process according to claim 3, wherein the crude reaction mixture fed into the
20 reaction with the DMC catalyst includes an amount of unreacted ethylene oxide and/or
other alkylene oxide and/or starter.
5. A process according to any preceding claim, wherein the alkylene oxides are
selected from cyclohexene oxide, styrene oxide, ethylene oxide, propylene oxide,
butylene oxide, substituted cyclohexene oxides (such as limonene oxide, C10H16O or 2-
25 (3,4-epoxycyclohexyl)ethyltrimethoxysilane, C11H22O), alkylene oxides (such as ethylene
oxide and substituted ethylene oxides), unsubstituted or substituted oxiranes (such as
oxirane, epichlorohydrin, 2-(2-methoxyethoxy)methyl oxirane (MEMO), 2-(2-(2-
methoxyethoxy)ethoxy)methyl oxirane (ME2MO), 2-(2-(2-(2-
methoxyethoxy)ethoxy)ethoxy)methyl oxirane (ME3MO), 1,2-epoxybutane, glycidyl
30 ethers, glycidyl esters, glycidyl carbonates, vinyl-cyclohexene oxide, 3-phenyl-1,2-
epoxypropane, 2,3-epoxybutane, isobutylene oxide, cyclopentene oxide, 2,3-epoxy-
1,2,3,4-tetrahydronaphthalene, indene oxide, and functionalized 3,5-dioxaepoxides,
preferably propylene oxide.
49
6. A process according to any preceding claim, wherein when one or more other
alkylene oxides are added to the reaction with the DMC catalyst in addition to ethylene
oxide, the ethylene oxide addition is increased mol/mol relative to the other alkylene
oxide(s) at the end part of the reaction.
7. A process according to any preceding claim, wherein the reaction 5 with the DMC
catalyst is carried out substantially in the absence of CO2.
8. A process according to any preceding claim, wherein the alkylene oxide residues
in the polycarbonate or polyester (poly)ol are ethylene oxide and/or propylene oxide
residues and optionally, in addition, other alkylene oxide residues.
10 9. A process according to claim 8, wherein the other alkylene oxide residues are
selected from cyclohexene oxide, styrene oxide, ethylene oxide, propylene oxide,
butylene oxide, substituted cyclohexene oxides (such as limonene oxide, C10H16O or
2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, C11H22O), alkylene oxides (such as
ethylene oxide and substituted ethylene oxides), unsubstituted or substituted oxiranes
15 (such as oxirane, epichlorohydrin, 2-(2-methoxyethoxy)methyl oxirane (MEMO), 2-(2-(2-
methoxyethoxy)ethoxy)methyl oxirane (ME2MO), 2-(2-(2-(2-
methoxyethoxy)ethoxy)ethoxy)methyl oxirane (ME3MO), 1,2-epoxybutane, glycidyl
ethers, glycidyl esters, glycidyl carbonates, vinyl-cyclohexene oxide, 3-phenyl-1,2-
epoxypropane, 2,3-epoxybutane, isobutylene oxide, cyclopentene oxide, 2,3-epoxy-
20 1,2,3,4-tetrahydronaphthalene, indene oxide, and functionalized 3,5-dioxaepoxides.
10. A process according to any preceding claim, wherein the reaction temperature of
the reaction with the DMC catalyst is in the range from about 50 to about 160°C,
preferably in the range from about 70 to about 140°C, more preferably from about 80 to
about 130°C.
25 11. A process according to any preceding claim, wherein the polycarbonate or
polyester (poly)ol (co)polymer further comprises ether linkages.
12. A process according to any preceding claim, wherein the DMC catalyst is based
upon Zn3[Co(CN)6]2 (zinc hexacyanocobaltate).
13. A process according to any preceding claim, wherein the polycarbonate (poly)ol
30 copolymer is a low molecular weight polycarbonate (poly)ol product having a molecular
weight (Mn) in the range 200 to 4000 Daltons as measured by Gel Permeation
Chromatography (GPC).
50
14. A process for producing a (poly)ol block copolymer according to claims 2-13,
wherein the starter compound has the formula (III):
Z ( RZ)a (III)
wherein Z can be any group which can have 1 or more, typically, 2 or more –RZ groups
attached to it and may be selected from optionally substituted alkylene, 5 alkenylene,
alkynylene, heteroalkylene, heteroalkenylene, heteroalkynylene, cycloalkylene,
cycloalkenylene, hererocycloalkylene, heterocycloalkenylene, arylene, heteroarylene, or
Z may be a combination of any of these groups, for example Z may be an alkylarylene,
heteroalkylarylene, heteroalkylheteroarylene or alkylheteroarylene group;
10 a is an integer which is at least 1, typically, at .least 2,optionally a is in the range of
between 1 or 2 and 8, optionally a is in the range of between 2 and 6;
wherein each RZ may be –OH, -NHR’, –SH, -C(O)OH, -P(O)(OR’)(OH), –PR’(O)(OH)2 or
–PR’(O)OH, optionally RZ is selected from –OH, -NHR’ or -C(O)OH, optionally each Rz
is –OH, -C(O)OH or a combination thereof (e.g. each Rz is –OH);
15 wherein R’ may be H, or optionally substituted alkyl, heteroalkyl, aryl, heteroaryl,
cycloalkyl or heterocycloalkyl, optionally R’ is H or optionally substituted alkyl; and
wherein Z’ corresponds to Rz, except that a bond replaces the labile hydrogen atom.
15. A process according to any of claims 2-14, wherein the first reaction is carried
out under CO2 pressure of less than 20 bar, more preferably, less than 10 bar, most
20 preferably, less than 8 bar.
16. A process according to any of claims 2-15, wherein the first reaction is a batch,
semi-batch, or continuous process.
17. A process according to any of claims 2-16, wherein the reactors are located in
series.
25 18. A process according to any of claims 2-17, wherein the first and second reactors
are effective to provide different reaction conditions, such as temperature and/or
pressure, to each other simultaneously.
19. A process according to any of claims 4-18, wherein the carbonate catalyst is
present in the crude reaction mixture.
51
20. A process according to any of claims 4-18, wherein the carbonate catalyst has
been removed from the crude reaction mixture prior to the addition to the reactor or
second reactor.
21. A process according to any of claims 2-20, wherein the temperature of reaction
in the first reactor is in the range about 0°C to 250 °C, preferably from 5 about 40 °C to
about 160 °C, more preferably from about 50 °C to 120 °C.
22. A process according to any of claims 2-21 wherein the carbonate catalyst is a
catalyst capable of producing polycarbonate chains with greater than 76% carbonate
linkages.
10 23. A process according to any of claims 2-22, wherein the carbonate catalyst is a
metal catalyst comprising phenol or phenolate ligands.
24. A process according to any of claims 2-23, wherein the product of the first
reaction is used to pre-activate the DMC catalyst in the second reaction, prior to addition
of ethylene oxide and optionally, alkylene oxide.
15 25. A process according to any of claim 2-24, wherein the same or different alkylene
oxides are used in the first or second reactions.
26. A process according to any preceding claim, further comprising a reaction
comprising the reaction of the (poly)ol block copolymer with a monomer or further
polymer to produce a higher polymer.
20 27. A (poly)ol block copolymer obtainable by the process according to claims 1-26,
comprising a general structure B-A-(B)n wherein block A is a polycarbonate or polyester
block, wherein n=t-1 and t = the number of reactive end residues on block A, wherein
block B is a polyether block and wherein > 70% of the copolymer chain ends are
terminated by primary hydroxyl groups.
25 28. A polyurethane comprising a block copolymer residue according to claim 27.
29. An isocyanate terminated polyurethane prepolymer comprising a block
copolymer residue according to claim 27.
30. A lubricant composition comprising a (poly)ol block copolymer of claim 27.
31. A surfactant composition comprising a (poly)ol block copolymer of claim 27.