The present invention relates to a process for the preparation of a composition
of organic peroxides comprising the mixture of at least one peroxydicarbonate and of
5 at least one peroxyester, preferably at least one hydroxyperoxyester; said composition
being prepared before being brought into contact with one or more monomers
comprising ethylenic unsaturations, preferably one or more halogenated vinyl
monomers, and more preferentially vinyl chloride.
The invention also relates to a process for the polymerization of one or more
10 ethylenically unsaturated monomers successively comprising the preparation of the
composition, as defined above, and bringing said composition into contact with one or
more ethylenically unsaturated monomers.
The present invention also relates to a halogenated vinyl polymer obtained by
polymerization of at least one halogenated ethylenically unsaturated monomer in the
15 presence of the composition as defined above.
Organic peroxides, in the liquid or solid form, are commonly used as
polymerization initiators for ethylenically unsaturated monomers for the synthesis of
various types of polymers, for example halogenated vinyl polymers, such as polyvinyl
chloride.
20 However, their use frequently presents a certain number of problems. This is
because organic peroxides generally constitute highly unstable entities as they
decompose relatively easily under the action of a slight contribution of heat, of
mechanical energy (friction or impact) and/or of incompatible contaminants. Thus, in
the event of uncontrolled elevation of their storage temperature, some organic
25 peroxides can undergo an autoaccelerated exothermic decomposition which can result
in fires and/or violent explosions. In addition, under these conditions, some of these
organic peroxides can release combustible vapours capable of reacting with any source
of ignition which can drastically increase, indeed even accelerate, the risks of violent
explosion. The result of this is that it is important to take appropriate precautionary
30 measures in terms of safety during the storage and transportation of organic peroxides.
In order to overcome these various disadvantages, organic peroxides are
sometimes stored at storage temperatures far below 0°C before being used as
polymerization initiators. Thus, organic peroxides are in particular packaged in the
form of aqueous emulsions which can comprise antifreezes. This is because the
35 presence of water makes it possible both to absorb and to dissipate the energy generated
in the event of exothermic decompositions of organic peroxides, while the role of the
antifreeze is to keep the emulsion in the liquid form, at temperatures of less than -10°C,
3
generally of less than -15°C, which makes it possible to limit the risks of an involuntary
exothermic decomposition of organic peroxides.
The aqueous emulsions generally contain, in addition, at least one emulsifier
having the advantage of lowering the interfacial tension between the aqueous phase
5 and the organic peroxide with the aim of facilitating the dispersion of the peroxide in
the form of droplets and of maintaining the size of them over time. This is because,
over time, the peroxide droplets can agglomerate together, bringing about an increase
in their mean size and in their maximum size which can result, in some cases, in a total
or partial phase separation and consequently in an overall destabilization of the
10 emulsion.
Furthermore, mixtures of organic peroxides can also be used as
polymerization initiators. To do this, the organic peroxides can be injected separately
into the reaction medium containing the ethylenically unsaturated monomers during
the polymerization or can be prepared upstream in a separate reactor in order to be
15 added at the start of the polymerization. In other words, in some cases, a mixture of the
organic peroxides, also known as premix, is employed upstream in a suitable reactor
before being added to the polymerization reactor. Such peroxide premixes are
generally packaged in aqueous emulsions.
However, the preparation of these premixes generally takes place at a
20 temperature greater than the storage temperature of the organic peroxides, that is to say
at a temperature at which the organic peroxides risk being decomposed. In the same
way, such premixes can also remain several hours, indeed even several days, before
they are used, in the reactor in which they were prepared at a temperature greater than
the storage temperature of the organic peroxides, which increases the risks of thermal
25 decomposition of the organic peroxides.
Thus, the preparation of premixes of organic peroxides generally results in
unstable compositions in which the organic peroxides are capable of decomposing as
a function of the temperature, which results in a decrease in the amount of free radicals
capable of being produced during the polymerization, which can result in a fall in the
30 quality of the polymer obtained.
One of the objectives of the present invention is thus to prepare mixtures of
organic peroxides not exhibiting the disadvantages described above, which are in
particular stable thermally and over time.
In particular, one of the aims of the present invention is to implement a process
35 making it possible to prepare mixtures of organic peroxides, which are stable, in which
the thermal degradation (or decomposition) of the peroxides is minimized. In other
words, one of the aims of the invention is to develop a process capable of ensuring,
4
indeed even of improving, the activity of the organic peroxides during the
polymerization.
A subject-matter of the present invention is thus a process for the preparation
of a composition of organic peroxides comprising the mixing of at least one
5 peroxydicarbonate and of at least one peroxyester before bringing said composition
into contact with one or more ethylenically unsaturated monomers.
In particular, the process according to the invention comprises a stage of
mixing at least one peroxydicarbonate and at least one peroxyester before bringing the
composition thus obtained into contact with one or more ethylenically unsaturated
10 monomers intended to polymerize together.
The process according to the invention thus exhibits the advantage of resulting
in a stable composition in which the thermal degradation of the organic peroxides is
minimized as a function of the time.
The process according to the invention makes it possible to prepare, upstream
15 of their introduction into a polymerization reactor, mixtures of organic peroxides which
can be stored and transported, at a temperature greater than that of the storage
temperature of the organic peroxides, in a stable way to the site of production of the
final polymer in order to be able to be used as is as polymerization initiators.
In particular, the process according to the invention makes it possible to
20 prepare a stable composition of organic peroxides in a suitable reactor occurring on the
site of production of the final polymer, at a temperature greater than that of the storage
temperature of the organic peroxides, and to leave it to stand within such a reactor in
complete safety for a greater or shorter period of time before being used effectively as
polymerization initiators.
25 In other words, the process makes it possible to minimize the formation of
free radicals in the premix of organic peroxides, which makes it possible to ensure the
quality of the polymer obtained and also a better yield.
The composition obtained by the process according to the invention can thus
be transported in complete safety within the factory for production of polymers, in
30 particular from one point to the other of the factory, and can result in polymeric
materials of good quality.
More particularly, the addition of the peroxyester makes it possible to
effectively stabilize the peroxydicarbonate.
Furthermore, the process according to the invention results in a composition
35 capable of bringing about a more homogeneous distribution of the organic peroxides
in the polymerization reactor, which improves the reaction time and promotes a
polymer of better quality being obtained. Such a homogeneity has in particular been
5
observed with respect to the addition of the peroxyester to a polymerization reactor
comprising the peroxydicarbonate.
Furthermore, the process according to the invention can advantageously be
carried out within the factory for production of polymers, which constitutes a saving
5 in time from an industrial viewpoint.
The composition of organic peroxides, which is obtained with the process
according to the invention, can advantageously be maintained at a higher temperature
than the storage temperature for several hours, indeed even several days, which offers
greater flexibility to the operator for the production of polymers.
10 In particular, the possibility of preserving such a composition at a temperature
greater than the storage temperature of the peroxides for a long period of time makes
it possible to economize on the amounts of organic peroxides necessary for the
production of the polymer.
The process according to the invention also exhibits the industrial advantage
15 of being able to prepare a stable composition which makes it possible to initiate the
polymerization of ethylenically unsaturated monomers at similar rates under
conditions reproducible from one polymerization reactor to another and to obtain
polymers having a similar quality and/or uniform mechanical and chemical properties.
Furthermore, the composition obtained by the process according to the
20 invention can be used several times over several hours, indeed even several days, after
its preparation, while retaining good stability.
Another subject-matter of the invention is a process for the polymerization of
one or more ethylenically unsaturated monomers successively comprising:
(i) the preparation of a composition as defined above,
25 (ii) bringing said composition into contact with one or more ethylenically
unsaturated monomers.
The polymerization process makes it possible to prepare a polymer of good
quality under reproducible conditions This is because the polymerization reaction time
is improved.
30 Another subject-matter of the invention is the use of the composition as
defined above for the polymerization or the copolymerization of one or more
ethylenically unsaturated monomers, in particular vinyl monomers, preferably
halogenated vinyl monomers, and more preferentially vinyl chloride.
The composition comprising the mixture of organic peroxides can thus be
35 used as polymerization initiators for the synthesis of polymers or of copolymers
obtained from one or more ethylenically unsaturated monomers.
6
In addition, the invention also relates to a halogenated vinyl polymer obtained
by polymerization of at least one halogenated ethylenically unsaturated monomer in
the presence of the composition as described above.
Other characteristics and advantages of the invention will become more
5 clearly apparent on reading the description and the examples which follow.
In what will follow and unless otherwise indicated, the limits of a range of
values are included in this range.
The expression “at least one” is equivalent to the expression “one or more”.
Within the meaning of the present invention, the expression “Rn
and Rm
represent a Cx-Cx4 alkyl group” means that Rn
and Rm
10 can represent Cx, Cx1, Cx2, Cx3
and Cx4, that is to say that the limits Cx and Cx4 are included.
Process for the preparation of the composition
15
As indicated above, the process according to the invention comprises the
mixing of at least one peroxydicarbonate and of at least one peroxyester before
bringing said composition into contact with one or more ethylenically unsaturated
monomers.
20 Preferably, the peroxydicarbonate corresponds to the following formula (I):
in which formula (I) R1
and R2
, which are identical or different, represent a
25 linear, branched or cyclic C1-C20 alkyl group which can comprise one or more
heteroatoms, preferably one or more oxygen atoms.
Preferably, R1
and R2
, which are identical or different, represent a linear,
branched or cyclic C1-C16, more preferentially C3-C12, in particular C3-C10, alkyl group
which can comprise, preferably interrupted by, one or more heteroatoms, preferably
30 one or more oxygen atoms.
Preferably, R1
and R2
, which are identical or different, represent a linear C1-
C16, more preferentially C3-C12, in particular C3-C10, alkyl group which can comprise
one or more heteroatoms, preferably one or more oxygen atoms.
7
Preferably, R1
and R2
, which are identical or different, represent a branched
C1-C16, more preferentially C3-C12, in particular C3-C10, alkyl group which can comprise
one or more heteroatoms, preferably one or more oxygen atoms.
Preferably, R1
and R2
, which are identical or different, represent a cyclic C3-
5 C12, in particular C3-C10, alkyl group which can comprise one or more heteroatoms,
preferably one or more oxygen atoms.
Preferably, R1
and R2
, which are identical or different, represent an alkyl
group, as defined above, which can be interrupted by one or more heteroatoms,
preferably one or more oxygen atoms.
10 Within the meaning of the present invention, the term “cyclic alkyl group” is
understood to mean a linear or branched alkyl group comprising a ring, preferably an
aromatic ring, preferably comprising 5 or 6 ring members.
Preferably, the heteroatom is an oxygen atom.
Preferably, R1
and R2
are identical and represent a linear or branched,
15 preferably branched, C2-C16, in particular C3-C12, more preferentially still C3-C10, alkyl
group.
Preferentially, R1
and R2
are identical and represent a linear or branched,
preferably branched, C2-C8 alkyl group.
The peroxydicarbonate is preferably chosen from the group consisting of di(2-
20 ethylhexyl) peroxydicarbonate, di(sec-butyl) peroxydicarbonate, bis(1-methylheptyl)
peroxydicarbonate, di(n-propyl) peroxydicarbonate, di(3-methoxybutyl)
peroxydicarbonate, diethyl peroxydicarbonate and their mixtures, preferably di(2-
ethylhexyl) peroxydicarbonate and di(sec-butyl) peroxydicarbonate.
Advantageously, the peroxydicarbonate is chosen from the group consisting
25 of di(2-ethylhexyl) peroxydicarbonate, sold under the trade name Luperox® 223, and
di(sec-butyl) peroxydicarbonate, sold under the trade name Luperox® 225.
Preferably, the peroxyester corresponds to the following formula (II):
30
in which formula (II) R3
and R4
, which are identical or different, represent a
linear, branched or cyclic C1-C20 alkyl group which can comprise one or more
8
heteroatoms, preferably one or more oxygen atoms, and/or optionally substituted by
one or more hydroxyl groups.
Preferably, R3
and R4
, which are identical or different, represent a linear or
branched C4-C20, preferably C7-C20, preferably C7-C16, in particular C7-C10, alkyl
5 group which can comprise one or more heteroatoms, preferably one or more oxygen
atoms, and/or optionally substituted by one or more hydroxyl groups.
Preferably, R3
and R4
, which are identical or different, represent a linear C4-
C20, preferably C7-C20, preferably C7-C16, in particular C7-C10, alkyl group which can
comprise one or more heteroatoms, preferably one or more oxygen atoms, and/or
10 optionally substituted by one or more hydroxyl groups.
Preferably, R3
and R4
, which are identical or different, represent a branched
C4-C20, preferably C7-C20, preferably C7-C16, in particular C7-C10, alkyl group which
can comprise one or more heteroatoms, preferably one or more oxygen atoms, and/or
optionally substituted by one or more hydroxyl groups.
Preferably, R3
and R4
15 , which are identical or different, represent a cyclic C4-
C20, preferably C7-C20, preferably C7-C16, in particular C7-C10, alkyl group which can
comprise one or more heteroatoms, preferably one or more oxygen atoms, and/or
optionally substituted by one or more hydroxyl groups.
Within the meaning of the present invention, the term “cyclic alkyl group” is
20 understood to mean a linear or branched alkyl group additionally comprising a ring,
preferably an aromatic ring, preferably comprising 5 or 6 ring members.
In other words, it is understood within the meaning of the present invention,
a cyclic alkyl group comprises a linear or branched, preferably C2-C4, alkyl group and
a ring, preferably an aromatic ring, preferably comprising 5 or 6 ring members.
25 Preferably, the cyclic alkyl group comprises a branched, preferentially C2-C4,
alkyl group and an aromatic ring preferably comprising 5 or 6 ring members.
Preferably, R3
and R4
, which are identical or different, represent an alkyl
group, as defined above, which can be interrupted by one or more heteroatoms,
preferably one or more oxygen atoms, and/or optionally substituted by one or more
30 hydroxyl groups.
Preferably, R3
and R4
, which are identical or different, represent a linear,
branched or cyclic C1-C20 alkyl group which can be optionally substituted by one or
more hydroxyl groups.
Preferably, R3
represents a linear or branched C4-C20, preferably C7-C20,
35 preferably C7-C16, in particular C7-C10, alkyl group which can comprise, preferably
interrupted by, one or more heteroatoms, preferably one or more oxygen atoms, and R4
represents a linear or branched C1-C7, preferably C2-C6, alkyl group optionally
9
substituted by one or more hydroxyl groups, or a cyclic C7-C16, in particular C7-C10,
alkyl group.
Preferably, R3
represents a branched C7-C20, preferably C4-C20, preferably C7-
C16, in particular C7-C10, alkyl group which can comprise, preferably interrupted by,
one or more heteroatoms, preferably one or more oxygen atoms, and R4
5 represents a
branched C1-C7, preferably C2-C6, alkyl group optionally substituted by one or more
hydroxyl groups.
Preferably, the heteroatom is an oxygen atom.
Preferably, in the formula (II):
- R
3
10 represents a linear, branched or cyclic, preferably branched, C4-C20,
preferably C7-C20, preferably C7-C16, in particular C7-C10, alkyl group
which can comprise, preferably interrupted by, one or more oxygen atoms,
preferably one oxygen atom;
- R
4
represents:
15 i) a linear or branched, preferably branched, C7-C20, preferably C7-C16,
in particular C7-C9, alkyl group which can comprise, preferably
interrupted by, one or more oxygen atoms, preferably one oxygen atom;
ii) a linear or branched, preferably branched, C1-C7, preferably C2-C6,
alkyl group optionally substituted by one or more hydroxyl groups,
20 iii) a cyclic C7-C10, in particular cyclic C9, alkyl group.
Preferentially, in the formula (II), R3
represents a linear or branched,
preferably branched, C4-C20, preferably C7-C20, preferably C7-C16, in particular C7-C10,
alkyl group.
Preferentially, in the formula (II), R4
represents:
25 - a linear or branched, preferably branched, C1-C7, preferably C2-C6, in
particular C4 or C6, alkyl group optionally substituted by one or more hydroxyl groups,
- a cyclic C7-C10, in particular C9, alkyl group.
Preferentially, in the formula (II), when R4
represents a cyclic C7-C10 alkyl
group, R4
then comprises a linear or branched, preferably branched, C2-C4, in particular
30 C3, alkyl group, and a ring, preferably an aromatic ring, preferably comprising 5 or 6
ring members.
More preferably still, R4
represents a linear or branched, preferably branched,
C1-C7, preferably C2-C6, in particular C6, alkyl group substituted by one or more
hydroxyl groups, in particular one hydroxyl group.
35 Advantageously, in the formula (II):
- R
3
represents a linear or branched, preferably branched, C4-C20, preferably
C7-C20, preferably C7-C16, in particular C7-C10, alkyl group,
10
- R
4
represents a linear or branched, preferably branched, C1-C7, preferably
C2-C6, alkyl group optionally substituted by one or more hydroxyl groups.
The peroxyester is preferably chosen from the group consisting of α-cumyl
peroxyneodecanoate, α-cumyl peroxyneoheptanoate, 2,4,4-trimethylpent-2-yl
5 peroxyneodecanoate, tert-butyl peroxy(n-heptanoate), tert-butyl peroxyneodecanoate,
α-cumyl peroxy(n-heptanoate), tert-amyl peroxy(n-heptanoate), tert-butyl
peroxyneoheptanoate, 2,5-dimethyl-2,5-di(2-ethylhexanoylperoxy)hexane, tert-amyl
peroxy(2-ethylhexanoate), tert-butyl peroxy(2-ethylhexanoate), 1,1,3,3-
tetramethylbutyl peroxy(2-ethylhexanoate), hydroxyperoxyesters, tert-amyl
10 peroxyneodecanoate, 1,1,3,3-tetramethylbutyl peroxyneodecanoate, 1,1,3,3-
tetramethylbutyl peroxypivalate, tert-hexyl peroxyneodecanoate, tert-hexyl
peroxypivalate and their mixtures.
Preferably, the peroxyesters are chosen from the group consisting of
hydroxyperoxyesters.
15 The hydroxyperoxyesters are advantageously chosen from the group
consisting of 4-hydroxy-2-methylpentyl peroxyneodecanoate, 4-hydroxy-2-
methylpentyl peroxyneoheptanoate, 4-hydroxy-2-methylpentyl peroxy(2-
ethylhexanoate), 4-hydroxy-2-methylpentyl peroxy(2-phenylbutyrate), 4-hydroxy-2-
methylpentyl peroxy(2-phenoxypropionate), 4-hydroxy-2-methylpentyl peroxy(2-
20 butyloctanoate), 4-hydroxy-2-methylpentyl peroxyneohexanoate, 4-hydroxy-2-
methylpentyl peroxyneotridecanoate, 4-hydroxy-2-methylhexyl peroxyneohexanoate,
4-hydroxy-2-methylhexyl peroxyneodecanoate, 5-hydroxy-1,3,3-trimethylcyclohexyl
peroxyneodecanoate, 4-hydroxy-2,6-dimethyl-2,6-di(neohexanoylperoxy)heptane, 4-
hydroxy-2,6-dimethyl-2,6-di(neodecanoylperoxy)heptane, 3-hydroxy-1,1-
25 dimethylbutyl peroxy(2-ethylhexanoate), 3-hydroxy-1,1-dimethylbutyl
peroxyneodecanoate, 3-hydroxy-1,1-dimethylbutyl peroxyneoheptanoate and their
mixtures, preferably 3-hydroxy-1,1-dimethylbutyl peroxyneodecanoate.
Preferably, the peroxyester is chosen from the group consisting of tert-butyl
peroxyneodecanoate, tert-amyl peroxyneodecanoate, α-cumyl peroxyneoheptanoate,
30 hydroxyperoxyesters and their mixtures.
Preferably, the peroxyester is chosen from the group consisting of 3-hydroxy1,1-dimethylbutyl peroxyneodecanoate, sold under the trade name Luperox® 610 by
Arkema, α-cumyl peroxyneoheptanoate, sold under the trade name Luperox® 188,
tert-amyl peroxyneodecanoate, sold under the trade name Luperox® 546, and tert35 butyl peroxyneodecanoate, sold under the trade name Luperox® 10 by Arkema, and
their mixtures.
Preferably, the peroxyester is chosen from the group consisting of 3-hydroxy1,1-dimethylbutyl peroxyneodecanoate, sold under the trade name Luperox® 610 by
11
Arkema, and tert-butyl peroxyneodecanoate, sold under the trade name Luperox® 10
by Arkema, and their mixtures.
Advantageously, the peroxyester is 3-hydroxy-1,1-dimethylbutyl
peroxyneodecanoate, sold under the trade name Luperox® 610 by Arkema.
5 Preferably, the peroxydicarbonate/peroxyester ratio by weight varies from
1/99 to 99/1, preferentially from 2/98 to 98/2.
According to another embodiment, the peroxydicarbonate/peroxyester ratio
by weight varies from 10/90, in particular from 20/80, to 50/50.
According to another embodiment, the peroxydicarbonate/peroxyester ratio
10 by weight varies from 99/1, in particular from 97/3, in particular 90/10 and
preferentially 80/20, to 50/50.
The peroxydicarbonate and the peroxyester advantageously have a one hour
half-life temperature of less than or equal to 90°C, preferably of less than 90°C.
Furthermore, the peroxydicarbonate and the peroxyester advantageously have
15 a storage temperature of less than 0°C.
Preferably, the process according to the invention comprises the mixing:
(i) of at least one organic peroxide of formula (I):
in which formula (I) R1
and R2
, which are identical or different, represent
20 a linear, branched or cyclic C1-C20 alkyl group which can comprise one
or more heteroatoms, preferably one or more oxygen atoms; and
(ii) of at least one organic peroxide of formula (II):
25
in which formula (II) R3
and R4
, which are identical or different, represent a
linear, branched or cyclic C1-C20 alkyl group which can comprise one or more
heteroatoms, preferably one or more oxygen atoms, and/or optionally substituted by
one or more hydroxyl groups.
12
Preferably, the process according to the invention comprises the mixing:
(i) of at least one organic peroxide of formula (I):
in which formula (I) R1
and R2
5 are identical and represent a linear or branched,
preferably branched, C1-C16, in particular C3-C12, more preferentially still C3-C10, alkyl
group; and
(ii) of at least one organic peroxide of formula (II):
10
in which formula (II):
- R
3
represents a linear, branched or cyclic, preferably branched, C4-C20,
preferably C7-C20, preferably C7-C16, in particular C7-C9, alkyl group
which can comprise, preferably be interrupted by, one or more oxygen
15 atoms, preferably one oxygen atom;
- R
4
represents:
i) a linear or branched, preferably branched, C7-C20, preferably C7-C16, in
particular C7-C10, alkyl group which can comprise, preferably be
interrupted by, one or more oxygen atoms, preferably one oxygen atom;
20 ii) a linear or branched, preferably branched, C1-C7, preferably C2-C6,
alkyl group optionally substituted by one or more hydroxyl groups,
iii) a cyclic C7-C10, in particular cyclic C9, alkyl group.
Advantageously, in accordance with this preferred embodiment, in the
formula (I), R1
and R2
25 are identical and represent a linear or branched, preferably
branched, C1-C6, in particular C1-C4, alkyl group.
13
Advantageously again, in accordance with this preferred embodiment, in the
formula (I), R1
and R2
are identical and represent a linear or branched, preferably
branched, C7-C16, in particular C7-C12, more preferentially still C7-C9, alkyl group.
Advantageously again, in accordance with this preferred embodiment, in the
formula (II), R4
5 represents a linear or branched, preferably branched, C1-C7, preferably
C2-C6, alkyl group optionally substituted by one or more hydroxyl groups.
Advantageously again, in accordance with this preferred embodiment, in the
formula (II), R4
represents a linear or branched, preferably branched, C1-C7, preferably
C2-C6, alkyl group substituted by one or more hydroxyl groups, in particular one
10 hydroxyl group.
More advantageously, the process according to the invention comprises the
mixing:
(a) of at least one organic peroxide of formula (I) chosen from the group
consisting of di(2-ethylhexyl) peroxydicarbonate, in particular sold under the
15 trade name Luperox® 223, di(sec-butyl) peroxydicarbonate, in particular sold
under the trade name Luperox® 225, and their mixtures; and
(b) of at least one organic peroxide of formula (II) chosen from the group
consisting of tert-butyl peroxyneodecanoate, sold under the trade name
Luperox® 10, tert-amyl peroxyneodecanoate, sold under the trade name
20 Luperox® 546, α-cumyl peroxyneoheptanoate, sold under the trade name
Luperox® 188, and hydroxyperoxyesters, as defined above, preferably 3-
hydroxy-1,1-dimethylbutyl peroxyneodecanoate, in particular sold under the
trade name Luperox® 610.
In accordance with this advantageous embodiment, the organic peroxide of
25 formula (II) is chosen from tert-butyl peroxyneodecanoate and hydroxyperoxyesters.
Advantageously again, in accordance with this embodiment, the organic
peroxide of formula (II) is a hydroxyperoxyester, preferably 3-hydroxy-1,1-
dimethylbutyl peroxyneodecanoate.
Preferably, the process according to the invention comprises the mixing:
30 (i) of at least one peroxydicarbonate, as defined above, and
(ii) of at least one peroxyester of formula (II), as defined above,
preferably chosen from the group consisting of tert-butyl
peroxyneodecanoate, in particular sold under the trade name Luperox® 10,
tert-amyl peroxyneodecanoate, sold under the trade name Luperox® 546, tert35 amyl peroxyneodecanoate, sold under the trade name Luperox® 546, and
hydroxyperoxyesters, preferably 3-hydroxy-1,1-dimethylbutyl
peroxyneodecanoate, in particular the 3-hydroxy-1,1-dimethylbutyl
peroxyneodecanoate sold under the trade name Luperox® 610.
14
Preferably, the process according to the invention comprises the mixing of at
least one peroxydicarbonate and of at least one peroxyester, as are defined above, in
an aqueous phase.
The aqueous phase preferentially comprises at least one emulsifying agent
5 and water.
The water can be present in a content ranging from 50% to 98% by weight,
with respect to the total weight of the composition.
Preferably, the process according to the invention comprises the addition of
at least one emulsifying agent.
10 Preferably, the emulsifying agent is chosen from the group consisting of
cellulose ether derivatives, partially hydrolysed poly(vinyl acetates), non-ionic
surfactants and their mixtures.
The non-ionic surfactant, which is or is not oxyalkylenated, is preferably
chosen from the group consisting of fatty alcohols, fatty acids, (hydrogenated or non15 hydrogenated) vegetable or animal oils, glucoside esters, sorbitan esters (Span),
alkoxylated sorbitan esters (Tween); or their mixtures.
Preferably, the emulsifying agent is chosen from the group consisting of
partially hydrolysed poly(vinyl acetates).
More preferentially, the emulsifying agent is chosen from the group
20 consisting of poly(vinyl acetates) having a degree of hydrolysis ranging from 70% to
90% or a degree of hydrolysis ranging from 40% to 60%.
The process according to the invention can also comprise the addition of one
or more additives intended to provide the final composition with specific
properties/characteristics. These additives will ideally be present for the final
25 polymerization or copolymerization.
The additive can be chosen from the group consisting of anti-foaming agents,
chain-transfer agents, chain extenders, pH regulators, plasticizers and their mixtures.
Preferably, the process according to the invention comprises the addition of
at least one plasticizer, preferably chosen from the group consisting of phthalates,
30 adipates, benzoates and the hydrogenated derivatives of these molecules, including in
particular diisononylcyclohexane and diisononyl cyclohexanedicarboxylate and their
mixtures.
Preferably, in the process according to the invention, the mixture of at least
one peroxydicarbonate and of at least one peroxyester, as are defined above, is
35 employed at a temperature ranging from -10°C to 50°C, in particular at a temperature
ranging from 0°C to 30°C.
15
Preferably, the composition obtained according to the process according to
the invention is liquid, in particular at a temperature ranging from -10°C to 50°C,
especially at a temperature ranging from 0°C to 30°C.
Preferably, the process according to the invention comprises at least:
5 (a) the mixing of at least one peroxydicarbonate and of at least one
peroxyester, as are defined above, in an aqueous phase as defined above,
(b) the emulsification of said mixture.
In particular, the process according to the invention successively comprises:
(a) the mixing of at least one peroxydicarbonate and of at least one
10 peroxyester, as are defined above, in an aqueous phase as defined above,
(b) the emulsification of said mixture.
More particularly, the process according to the invention successively
comprises:
- the addition of at least one emulsifying agent, as defined above, to water,
15 in order to obtain an aqueous phase,
- the mixing of at least one peroxydicarbonate and of at least one
peroxyester, as are defined above, in the aqueous phase,
- the emulsification of said mixture.
20 Preferably, the peroxydicarbonate and/or the peroxyester is (or are) diluted
using at least one organic solvent or is (or are) in the aqueous emulsion form before
being mixed in accordance with the process according to the invention.
In other words, before mixing, the peroxydicarbonate and/or the peroxyester
can be in a composition existing in a liquid form diluted by at least one organic solvent
25 or placed in aqueous emulsion.
Preferably, the peroxydicarbonate and the peroxyester is (or are) diluted using
at least one organic solvent or is (are) in the aqueous emulsion form before being mixed
in accordance with the process according to the invention.
More preferentially, the peroxydicarbonate and the peroxyester is (are) in the
30 aqueous emulsion form before being mixed in accordance with the process according
to the invention.
In other words, the process for the preparation of the composition of organic
peroxides comprises the mixing of at least one peroxydicarbonate, as defined above,
and of at least one peroxyester, as defined, before bringing said composition into
35 contact with one or more ethylenically unsaturated monomers; at least one of said
organic peroxides, preferably said organic peroxides, being in the form of an aqueous
emulsion.
16
Preferentially, the process for the preparation of the composition of organic
peroxides comprises the mixing of at least one peroxydicarbonate, as defined above,
being in the form of an aqueous emulsion, and of at least one peroxyester, as defined
above, being in the form of an aqueous emulsion, before bringing the composition thus
5 obtained into contact with one or more ethylenically unsaturated monomers.
Alternatively, the peroxydicarbonate and/or the peroxyester is (or are) in the
pure form.
In particular, the peroxydicarbonate and the peroxyester are in the pure form.
According to one embodiment, the process for the preparation of the
10 composition of organic peroxides comprises the mixing of at least one
peroxydicarbonate, as defined above, being in the pure form, and of at least one
peroxyester, as defined above, being in the pure form, before bringing the composition
thus obtained into contact with one or more ethylenically unsaturated monomers.
According to a preferential characteristic of the invention, the process for the
15 preparation of the composition comprises the mixing of at least one peroxydicarbonate
and of at least one peroxyester, before the introduction of the composition thus
obtained into a polymerization reactor, said polymerization reactor preferably
comprising one or more ethylenically unsaturated monomers.
Thus, the process advantageously employs a mixture prepared before
20 injection of the composition into a polymerization reactor, said polymerization reactor
preferably comprising one or more ethylenically unsaturated monomers.
According to another preferential characteristic, the process according to the
invention comprises the mixing of at least one peroxydicarbonate and of at least one
peroxyester in an aqueous phase devoid of the ethylenically unsaturated monomer(s)
25 described above.
Preferably, the ethylenically unsaturated monomers are chosen from the group
consisting of vinyl halide monomers (i.e., halogenated vinyl monomers) and more
preferentially vinyl chloride.
Advantageously, the process according to the invention comprises the
30 addition of at least one peroxyester, as defined above, to a composition comprising at
least one peroxydicarbonate, as defined above.
Thus, the stage of mixing the organic peroxides is advantageously a stage of
addition of at least one peroxyester, as defined above, to a composition comprising at
least one peroxydicarbonate, as defined above.
35 In accordance with this advantageous embodiment, the
peroxydicarbonate/peroxyester ratio by weight varies preferably from 99/1, in
particular from 97/3, especially 90/10 and preferentially 80/20, to 50/50.
17
In accordance with this embodiment, the addition of at least one peroxyester
makes it possible to improve the peroxydicarbonate stability.
Polymerization process
5
Another subject-matter of the invention is a process for the polymerization of
one or more ethylenically unsaturated monomers successively comprising:
(i) the preparation of a composition in accordance with the process as
described above,
10 (ii) bringing said composition into contact with one or more ethylenically
unsaturated monomers.
Preferably, stage (ii) of bringing into contact is carried out at least 30 minutes
after stage (i), preferably at least 1 hour after stage (i).
Preferably, the process is a process of polymerization of one or more vinyl
15 monomers, preferably halogenated vinyl monomers, and more preferentially of vinyl
chloride.
Mention may be made, as ethylenically unsaturated monomers, of acrylates,
vinyl esters, vinyl halide monomers, vinyl ethers, butadiene or vinylaromatic
compounds, such as styrene.
20 Preferably, the ethylenically unsaturated monomers are chosen from the group
consisting of vinyl halide monomers (i.e., halogenated vinyl monomers) and more
preferentially vinyl chloride.
Preferably, bringing the composition into contact with one or more
ethylenically unsaturated monomers comprises the introduction of said composition
25 into a polymerization reactor comprising the ethylenically unsaturated monomer(s).
Preferably, the preparation of the composition in accordance with the process
described above takes place in a separate reactor from the reactor in which the
composition is brought into contact with the ethylenically unsaturated monomer(s)
described above.
30 Preferably, stage (i) of preparation of the composition can be used for several
polymerizations. In other words, stage (i) of preparation of the composition can be
followed by several stages (ii) of bringing said composition into contact with one or
more ethylenically unsaturated monomers.
35 Use
The present invention also relates to the use of the composition as defined
above for the polymerization or the copolymerization of one or more ethylenically
18
unsaturated monomers, in particular vinyl monomers, preferably halogenated vinyl
monomers, and more preferentially vinyl chloride.
In particular, the composition is used for the manufacture of a halogenated
vinyl polymer, preferably poly(vinyl chloride).
5 Preferentially, the invention relates to the use of at least one peroxyester, as
described above, for improving the stability of at least one peroxydicarbonate, as
described above.
10 Polymer
Another subject-matter of the present relates to the halogenated vinyl polymer
obtained by polymerization of at least one ethylenically unsaturated monomer, as
defined above, in the presence of the composition as defined above.
15 Preferably, the invention relates to the poly(vinyl chloride) obtained by
polymerization of vinyl chloride in the presence of the composition as obtained by the
process as defined according to the invention, in particular in the presence of a mixture
of organic peroxides, as are defined above.
The following examples serve to illustrate the invention without, however,
20 exhibiting a limiting nature.
19
EXAMPLES
Example 1
5 The following composition I was prepared from the ingredients, mentioned in
the table below, the contents of which have been shown as percentage by weight, with
respect to the total weight of the composition.
[Table 1]
Di(2-ethylhexyl) peroxydicarbonate (Luperox® 223) 11.3%
3-Hydroxy-1,1-dimethylbutyl peroxyneodecanoate 2%
Polyvinyl alcohol
(Alcotex 552 P)
Polyvinyl alcohol
(Gohsenol GH20)
Water Q.s. for 100
10 Tests carried out:
The content by weight of peroxydicarbonate (di(2-ethylhexyl)
peroxydicarbonate – Luperox® 223) was measured at a temperature of 15°C over a
period of 96 hours:
15 - in the composition I in the presence of a peroxyester (3-hydroxy-1,1-
dimethylbutyl peroxyneodecanoate – Luperox® 610),
- in a composition identical to the composition I but devoid of peroxyester;
the peroxyester being replaced by water.
20 Figure 1 represents, on the one hand, the content by weight of di(2-ethylhexyl)
peroxydicarbonate alone, curve referenced Lx 223, and, on the other hand, the content
by weight of the peroxydicarbonate in the presence of 2% by weight of 3-hydroxy-1,1-
dimethylbutyl peroxyneodecanoate, curve referenced Lx 223, 610, as a function of the
time.
25
Results
20
Figure 1 shows that the content by weight of di(2-ethylhexyl)
peroxydicarbonate decreases less rapidly in the presence of 3-hydroxy-1,1-
dimethylbutyl peroxyneodecanoate over a period of 96 hours at a temperature of 15°C
5 than when the di(2-ethylhexyl) peroxydicarbonate is alone in the composition.
The results thus demonstrate that di(2-ethylhexyl) peroxydicarbonate is more
stable in the presence of 3-hydroxy-1,1-dimethylbutyl peroxyneodecanoate than alone
in the same composition.
10 Example II
In the following example, the content by weight of di(2-ethylhexyl)
peroxydicarbonate was measured at a temperature of 15°C over a period of 96 hours:
- in the composition I in the presence of the peroxyester (3-hydroxy-1,1-
15 dimethylbutyl peroxyneodecanoate – Luperox® 610),
- in a composition identical to the composition I but devoid of peroxyester,
- in a composition identical to the composition I but comprising 1% by
weight of peroxyester,
- in a composition identical to the composition I but comprising 3% by
20 weight of peroxyester,
- in a composition identical to the composition I but comprising 5% by
weight of peroxyester,
- in a composition identical to the composition I but comprising 10% by
weight of peroxyester,
25
Figure 2 represents, as a function of the time:
- the content by weight of di(2-ethylhexyl) peroxydicarbonate alone, curve
referenced Lx 223,
- the content by weight of peroxydicarbonate in the presence of 1% by
30 weight of 3-hydroxy-1,1-dimethylbutyl peroxyneodecanoate, curve
referenced Lx 223, 610 (1%),
- the content by weight of peroxydicarbonate in the presence of 2% by
weight of 3-hydroxy-1,1-dimethylbutyl peroxyneodecanoate, curve
referenced Lx 223, 610 (2%),
35 - the content by weight of peroxydicarbonate in the presence of 3% by
weight of 3-hydroxy-1,1-dimethylbutyl peroxyneodecanoate, curve
referenced Lx 223, 610 (3%),
21
- the content by weight of peroxydicarbonate in the presence of 5% by
weight of 3-hydroxy-1,1-dimethylbutyl peroxyneodecanoate, curve
referenced Lx 223, 610 (5%),
- the content by weight of peroxydicarbonate in the presence of 10% by
5 weight of 3-hydroxy-1,1-dimethylbutyl peroxyneodecanoate, curve
referenced Lx 223, 610 (10%).
Results
10 Figure 2 shows that the content by weight of di(2-ethylhexyl)
peroxydicarbonate decreases less rapidly in the presence of 3-hydroxy-1,1-
dimethylbutyl peroxyneodecanoate over a period of 96 hours at a temperature of 15°C
than when the di(2-ethylhexyl) peroxydicarbonate is alone in the composition.
The results thus demonstrate that di(2-ethylhexyl) peroxydicarbonate is more
15 stable in the presence of 3-hydroxy-1,1-dimethylbutyl peroxyneodecanoate than alone
in the same composition.
Example III
20 In the following example, the content by weight of di(2-ethylhexyl)
peroxydicarbonate was measured at a temperature of 15°C over a period of 96 hours:
- in the composition I in the presence of 2% by weight of peroxyester (3-
hydroxy-1,1-dimethylbutyl peroxyneodecanoate – Luperox® 610),
- in a composition identical to the composition I but devoid of peroxyester,
25 - in a composition identical to the composition I but comprising 2.5% by
weight of tert-butyl peroxyneodecanoate (Luperox® 10).
Figure 3 represents, as a function of the time:
- the content by weight of di(2-ethylhexyl) peroxydicarbonate alone, curve
30 referenced Lx 223,
- the content by weight of peroxydicarbonate in the presence of 2% by
weight of 3-hydroxy-1,1-dimethylbutyl peroxyneodecanoate, curve
referenced Lx 223, 610 (2%).
- the content by weight of peroxydicarbonate in the presence of 2.5% by
35 weight of tert-butyl peroxyneodecanoate, curve referenced Lx 223, Lup10
(2.5%).
Results
22
Figure 3 shows that the content by weight of di(2-ethylhexyl)
peroxydicarbonate decreases less rapidly in the presence of a peroxyester over a period
of 96 hours at a temperature of 15°C than when the di(2-ethylhexyl) peroxydicarbonate
5 is alone in the composition.
The results thus demonstrate that di(2-ethylhexyl) peroxydicarbonate is more
stable in the presence of a peroxyester than alone in the same composition and under
the same conditions.
Furthermore, it is found that di(2-ethylhexyl) peroxydicarbonate is more
10 stable in the presence of the hydroxyperoxyester, namely 3-hydroxy-1,1-dimethylbutyl
peroxyneodecanoate.

WE CLAIM:
1. Process for the preparation of a composition of organic peroxides comprising the
mixing of at least one peroxydicarbonate and of at least one peroxyester before bringing said
composition into contact with one or more ethylenically unsaturated monomers.
2. Process according to Claim 1, characterized in that the peroxydicarbonate
corresponds to the following formula (I):
in which formula (I) R1
and R2
, which are identical or different, represent a linear,
branched or cyclic C1-C20 alkyl group which can comprise one or more heteroatoms, preferably
one or more oxygen atoms.
3. Process according to Claim 2, characterized in that R1
and R2
, which are identical or
different, represent a linear or branched C1-C16, more preferentially C3-C12, in particular C3-C10,
alkyl group which can comprise, preferably interrupted by, one or more heteroatoms, preferably
one or more oxygen atoms.
4. Process according to any one of Claims 1 to 3, characterized in that R1
and R2
are
identical and represent a linear or branched, preferably branched, C2-C8 alkyl group.
5. Process according to any one of the preceding claims, characterized in that the
peroxydicarbonate is chosen from the group consisting of di(2-ethylhexyl) peroxydicarbonate,
di(sec-butyl) peroxydicarbonate, bis(1-methylheptyl) peroxydicarbonate, di(n-propyl)
peroxydicarbonate, di(3-methoxybutyl) peroxydicarbonate, diethyl peroxycarbonate and their
mixtures.
6. Process according to any one of the preceding claims, characterized in that the
peroxyester corresponds to the following general formula (II):
24
in which formula (II) R3
and R4
, which are identical or different, represent a linear,
branched or cyclic C1-C20 alkyl group which can comprise, preferably interrupted by, one or more
heteroatoms, preferably one or more oxygen atoms, and/or optionally substituted by one or more
hydroxyl groups.
7. Process according to Claim 6, characterized in that:
- R
3
represents a linear, branched or cyclic, preferably branched, C4-C20, preferably C7-
C20, preferably C7-C16, in particular C7-C10, alkyl group which can comprise,
preferably interrupted by, one or more oxygen atoms, preferably one oxygen atom;
- R4 represents:
i) a linear or branched, preferably branched, C7-C20, preferably C7-C16, in
particular C7-C10, alkyl group which can comprise, preferably interrupted by, one or
more oxygen atoms, preferably one oxygen atom;
ii) a linear or branched, preferably branched, C1-C7, preferably C2-C6, alkyl group
optionally substituted by one or more hydroxyl groups;
iii) a cyclic C7-C10, in particular cyclic C9, alkyl group.
8. Process according to any one of the preceding claims, characterized in that the
peroxyester is chosen from the group consisting of α-cumyl peroxyneodecanoate, α-cumyl
peroxyneoheptanoate, 2,4,4-trimethylpent-2-yl peroxyneodecanoate, tert-butyl peroxy(nheptanoate), tert-butyl peroxyneodecanoate, α-cumyl peroxy(n-heptanoate), tert-amyl peroxy(nheptanoate), tert-butyl peroxyneoheptanoate, 2,5-dimethyl-2,5-di(2-
ethylhexanoylperoxy)hexane, tert-amyl peroxy(2-ethylhexanoate), tert-butyl peroxy(2-
ethylhexanoate), 1,1,3,3-tetramethylbutyl peroxy(2-ethylhexanoate), hydroxyperoxyesters, tertamyl peroxyneodecanoate, 1,1,3,3-tetramethylbutyl peroxyneodecanoate, 1,1,3,3-
tetramethylbutyl peroxypivalate, tert-hexyl peroxyneodecanoate, tert-hexyl peroxypivalate and
their mixtures.
9. Process according to any one of the preceding claims, characterized in that the
peroxyester is a hydroxyperoxyester chosen from the group consisting of 4-hydroxy-2-
methylpentyl peroxyneodecanoate, 4-hydroxy-2-methylpentyl peroxyneoheptanoate, 4-hydroxy2-methylpentyl peroxy(2-ethylhexanoate), 4-hydroxy-2-methylpentyl peroxy(2-phenylbutyrate),
4-hydroxy-2-methylpentyl peroxy(2-phenoxypropionate), 4-hydroxy-2-methylpentyl peroxy(2-
butyloctanoate), 4-hydroxy-2-methylpentyl peroxyneohexanoate, 4-hydroxy-2-methylpentyl
peroxyneotridecanoate, 4-hydroxy-2-methylhexyl peroxyneohexanoate, 4-hydroxy-2-
methylhexyl peroxyneodecanoate, 5-hydroxy-1,3,3-trimethylcyclohexyl peroxyneodecanoate, 4-
hydroxy-2,6-dimethyl-2,6-di(neohexanoylperoxy)heptane, 4-hydroxy-2,6-dimethyl-2,6-
di(neodecanoylperoxy)heptane, 3-hydroxy-1,1-dimethylbutyl peroxy(2-ethylhexanoate), 3-
25
hydroxy-1,1-dimethylbutyl peroxyneodecanoate, 3-hydroxy-1,1-dimethylbutyl
peroxyneoheptanoate and their mixtures, preferably 3-hydroxy-1,1-dimethylbutyl
peroxyneodecanoate.
10. Process according to any one of the preceding claims, characterized in that the
peroxyester is chosen from the group consisting of tert-butyl peroxyneodecanoate, tert-amyl
peroxyneodecanoate, α-cumyl peroxyneoheptanoate and hydroxyperoxyesters.
11. Process according to any one of the preceding claims, characterized in that it
comprises the mixing of at least one peroxydicarbonate and of at least one peroxyester in an
aqueous phase.
12. Process according to any one of the preceding claims, characterized in that the
peroxydicarbonate and/or the peroxyester is (or are) diluted using at least one organic solvent or
is (or are) in the aqueous emulsion form.
13. Process according to any one of the preceding claims, characterized in that it
comprises the addition of at least one emulsifying agent, preferably chosen from the group
consisting of cellulose ether derivatives, partially hydrolysed poly(vinyl acetates), non-ionic
surfactants and their mixtures.
14. Process according to any one of the preceding claims, characterized in that the
mixture is prepared at a temperature ranging from -10°C to 50°C, preferably at a temperature
ranging from 0°C to 30°C.
15. Process according to any one of the preceding claims, characterized in that the
mixture is prepared before injection of said composition into a polymerization reactor comprising
one or more ethylenically unsaturated monomers.
16. Process for the polymerization of one or more ethylenically unsaturated monomers
successively comprising:
(i) the preparation of a composition in accordance with the process as defined according
to any one of Claims 1 to 14,
(ii) bringing said composition into contact with one or more ethylenically unsaturated
monomers.
17. Use of the composition obtained according to any one of Claims 1 to 13 for the
polymerization or the copolymerization of one or more ethylenically unsaturated monomers.
26
18. Use according to Claim 17, characterized in that the ethylenically unsaturated
monomers are halogenated vinyl monomers and more preferentially vinyl chloride.
19. Halogenated vinyl polymer obtained by polymerization of at least one ethylenically
unsaturated monomer in the presence of a composition as defined according to any one of Claims
1 to 13.