U.S. patent application number 12/801447 was filed with the patent office on 2010-09-30 for polymerisation of ethylenically unsaturated monomers.
This patent application is currently assigned to Croda International PLC. Invention is credited to Bruce C. Gilbert, Richard J. Harrison, Derek J. Irvine, Andrew F. Parsons.
Application Number | 20100249321 12/801447 |
Document ID | / |
Family ID | 9955481 |
Filed Date | 2010-09-30 |
United States Patent
Application |
20100249321 |
Kind Code |
A1 |
Harrison; Richard J. ; et
al. |
September 30, 2010 |
Polymerisation of ethylenically unsaturated monomers
Abstract
Ethylenically unsaturated, particularly acrylic, monomers are
polymerised using a catalyst system including a manganese carbonyl
initiator, an organic halogen reactive substrate and an allylic
halide chain termination agent. Desirably the manganese carbonyl
initiator is a dimanganese compound, particularly dimanganese
decacarbonyl (Mn.sub.2(CO).sub.10). The catalysis mechanism appears
to involve initiator homolysis, abstraction of halogen from the
reactive substrate forming an organic free radical which acts as a
chain initiator for polymerisation and eventual reaction of the
propagating chain radical with the chain terminating agent. The
speed or extent of reaction may be modified by the inclusion of
Lewis acids in the reaction mixture. The resulting polymers are
telechelic and may have different end groups. The polymers can be
reacted further to functionalise them and/or to form block
copolymers.
Inventors: |
Harrison; Richard J.;
(Godmanchester, GB) ; Gilbert; Bruce C.;
(Heslington, GB) ; Parsons; Andrew F.;
(Heslington, GB) ; Irvine; Derek J.; (Yarm,
GB) |
Correspondence
Address: |
JONES DAY
222 EAST 41ST ST
NEW YORK
NY
10017
US
|
Assignee: |
Croda International PLC
Google
GB
|
Family ID: |
9955481 |
Appl. No.: |
12/801447 |
Filed: |
June 9, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10549856 |
Jun 26, 2006 |
7759443 |
|
|
PCT/GB04/01260 |
Mar 24, 2004 |
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12801447 |
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Current U.S.
Class: |
525/54.2 ;
525/123; 525/54.24; 525/55; 526/258; 526/266; 526/291 |
Current CPC
Class: |
C08F 4/50 20130101 |
Class at
Publication: |
525/54.2 ;
526/291; 526/266; 526/258; 525/55; 525/123; 525/54.24 |
International
Class: |
C08F 251/00 20060101
C08F251/00; C08F 14/00 20060101 C08F014/00; C08F 24/00 20060101
C08F024/00; C08F 26/06 20060101 C08F026/06; C08F 26/10 20060101
C08F026/10; C08L 75/00 20060101 C08L075/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 25, 2003 |
GB |
0306820.2 |
Claims
1. A polymer or copolymer of one or more ethylenically unsaturated
monomers having at one end of the (co)polymeric chain a residue of
a reactive substrate and a residue of an allylic halogen
substituted chain termination agent at the other.
2. A polymer or copolymer as claimed in claim 1 wherein the
(co)polymeric chain includes residues of one or more monomers
selected from acrylic monomers, vinyl acetate, vinyl halide,
styrene, .alpha.-methyl styrene, vinyl toluene, vinyl caprolactone,
vinyl caprolactam and/or N-vinyl pyrollidone.
3. A polymer or copolymer as claimed in claim 2 wherein the monomer
includes at least 40 mole % of acrylic monomer or monomers.
4. A polymer or copolymer as claimed in claim 2 wherein the acrylic
monomer is or includes monomer of the formula (IV):
R.sup.10--CR.sup.11.dbd.CR.sup.12--COR.sup.13 (IV) where R.sup.10
is methyl or, and desirably, hydrogen; R.sup.11 is methyl or, and
desirably, hydrogen; R.sup.12 is methyl or hydrogen; provided that
at least one of R.sup.11 and R.sup.12 is hydrogen, and R.sup.13 is
--OR.sup.14, or --NR.sup.15R.sup.16 where R.sup.14, R.sup.15 and
R.sup.16 are each hydrogen, hydrocarbyl, or a polyalkyleneoxy
chain.
5. A method as claimed in claim 4 wherein the monomer is or
includes one or more acrylate or methacrylate ester; acrylic or
methacrylic acid; acrylic or methacrylic amide; or a sulphonated
acrylic monomer.
6. A polymer or copolymer as claimed in claim 1 wherein the residue
of the chain terminating agent is or includes the residue of an
allylic halogen substituted chain termination agent of the formula
(II): Hal-CHR.sup.3--CR.sup.4.dbd.CH2 (II) where Hal is halogen;
and R.sup.3 and R.sup.4 are each independently hydrogen, or a
group: (Link).sub.n-R.sup.5, where: n is 0 or 1, Link is a linking
group; and R.sup.5 is halogen, glycidyl, an ethylenic double bond,
carbonyl, carboxyl, cyano, hydroxyl, amino or quaternary amino or
ammonium, a phosphorus containing species, a sulphur containing
species, a hydrogen bond donor or acceptor, an aromatic ring, a
heterocyclic ring, or a saccharide residue.
7. A polymer or copolymer as claimed in claim 6 wherein Hal is a
chlorine or bromine atom.
8. A polymer or copolymer as claimed in claim 1 wherein the
reactive substrate is also a chain terminating agent.
9. A polymer or copolymer as claimed in claim 1 wherein the residue
of the reactive substrate is or includes the residue of a halogen
substituted alkane, alcohol or carboxylic acid ester, an aromatic
substituted alkyl halide, a ring substituted benzyl halide, and/or
a sulphonyl halide.
10. A metpolymer or copolymer as claimed in claim 9 wherein the
reactive substrate has multiple halogen substitution.
11. A polymer or copolymer as claimed in claim 9 wherein the
reactive substrate is or includes at least one of carbon
tetrachloride, carbon tetrabromide, chlorotribromomethane,
trichloro-methane, tribromomethane, dichloromethane,
dibromomethane, 1,1-dichloroethane, 1,1-dibromoethane,
1,1,1-trichloroethane, 1,1,1-tribromoethane, 2,2-dichloroethanol,
2,2-dibromoethanol, 2,2,2-trichloroethanol, 2,2,2-tribromoethanol,
trichloroacetic acid, C.sub.1 to C.sub.6 alkyl esters of
trichloroacetic acid, C.sub.2 to C.sub.6 alkyl 2-bromo-2-methyl
propionates, benzyl halides, 2-halo-2-phenylethanes, 4-alkyl benzyl
halides, 4-fluorobenzyl bromide, 4-chloro-benzyl bromide,
4-fluorobenzyl chloride, 4-chlorobenzyl chloride,
1,2-di(bromomethyl)-benzene, benzene sulphonyl chloride and/or
toluene sulphonyl chloride.
12. A block copolymer comprising a block of a polymer or copolymer
of one or more ethylenically unsaturated monomers having at one end
of the (co)polymeric chain a residue of a reactive substrate and a
residue of an allylic halogen substituted chain termination agent
at the other, linked to at least one second polymer block
covalently bound to one or both ends of the first polymer
block.
13. A block copolymer as claimed in claim 12 wherein the second
block comprises a polyester, a polyhydroxyacid, a polyalkoxylate, a
polyurethane, a vinylic polymer or a polysaccharide.
14. A block copolymer as claimed in claim 13 wherein the polyester
is a polyterephthalate; the polyhydroxyacid is polyhydroxystearic
acid, polylactic acid or a polylactone; the poly-alkoxylate is
polyethylene glycol (PEG) or polypropylene glycol (PPG); the
polyurethane is based on the reactions between toluene
di-isocyanate or methylene diphenyldiisocyanate and polyols; the
vinylic polymer is an acrylate polymer; and the polysaccharide is a
dextrin or a starch.
15. A block copolymer as claimed in claim 14 wherein the polyester
is polyethylene terephthalate, the polylactone is polycaprolactone;
the vinylic polymer is polymethyl methacrylate (PMMA) or a
copolymer including residues of other (meth)acrylate esters or
polystyrene.
16. A method of making a block copolymer comprising a first block
of a polymer or copolymer of one or more ethylenically unsaturated
monomers having at one end of the (co)polymeric chain a residue of
a reactive substrate and a residue of an allylic halogen
substituted chain termination agent at the other and linked through
the residue of chain terminating agent to a second block comprising
a polyester, a polyhydroxyacid, a polyalkoxylate, a polyurethane, a
vinylic polymer or a polysaccharide, which comprises polymerising
the second block onto the first block.
17. A method of making a block copolymer comprising a first block
of a polymer or copolymer of one or more ethylenically unsaturated
monomers having at one end of the (co)polymeric chain a residue of
a reactive substrate and a residue of an allylic halogen
substituted chain termination agent at the other and linked through
the residue of chain terminating agent to a second block comprising
a polyester, a polyhydroxyacid, a polyalkoxylate, a polyurethane, a
vinylic polymer or a polysaccharide, which comprises reacting a
preformed second block onto the first block.
Description
[0001] This invention relates to a method of polymerising
ethylenically unsaturated monomers, which method can produce
telechelic polymers, in particular such a method using a catalyst
system including manganese compound(s), to the catalyst system,
novel (co)polymers made by the method and copolymers made by
further reaction based on the polymers.
[0002] Polymerising ethylenically unsaturated monomers by atom
transfer radical polymerisation (ATRP), e.g. using chelated copper
catalysts, can yield, particularly acrylic, polymers having well
controlled molecular weights with a narrow spread of molecular
weights. The ATRP reaction sequence is thought to involve
abstraction by the copper catalyst of a halogen atom from a
substrate molecule to give a radical which initiates
polymerisation, continuing until the chain radical end abstracts a
halogen atom from the halogen-copper catalyst species, regenerating
the catalyst which can react to start further polymer chains. The
polymer can react with further catalyst to recommence
polymerisation.
[0003] The use of manganese carbonyls, specifically dimanganese
decacarbonyl, as free radical polymerisation initiators has been
reported by Bamford, Chapter 3 of Reactivity, Mechanism and
Structure in Polymer Chemistry, Ed Jenkins and Ledwith (Wiley
1974), who described photolysis of manganese decacarbonyl in the
presence of carbon tetrachloride leading to the polymerisation of
methyl methacrylate to high conversion, and by Yagci and Hepuzer,
Macromolecules 1999, 32, 6367, who described the photolysis of
dimanganese decacarbonyl leading to a manganese pentacarbonyl
radical which abstracted a halogen atom from a halogenated solvent
to generate a carbon based free radical which was oxidised by an
onium salt to give a cationic initiator for polymerising epoxides
and vinyl ethers. Neither of these reports offers any suggestion
that polymer molecular weight can be controlled and repeating the
reaction described by Bamford leads to high molecular weight
materials.
[0004] The present invention is based on our discovery that using
manganese carbonyl free radical initiators in combination with a
halogen containing reactive substrate and an allylic halide chain
termination agent, enables a polymerisation reaction that can
produce polymers having controlled molecular weights and a
relatively narrow molecular weight distribution. Further, it is
possible to make polymers with functional residues at the chain
ends which differ from the bulk of the polymer chain (telechelic
polymers) and such telechelic polymers having different terminal
groups at opposite ends of the polymer chain. These telechelic
copolymers can be further reacted with monomer(s) by chain
extension polymerisation(s) or by reaction with pre-formed
polymeric blocks to produce block copolymers.
[0005] The present invention accordingly provides a method of
polymerising ethylenically unsaturated monomers in which at least
one ethylenically unsaturated monomer is polymerised using a
catalyst system having a manganese carbonyl radical initiator, a
halogen containing reactive substrate and an allylic halogen
substituted chain termination agent.
[0006] The invention further includes a method of free radical
polymerisation of ethylenically unsaturated monomers comprising:
[0007] 1 forming a free radical by homolysis of a Mn--Mn or C--Mn
bond in a manganese carbonyl radical initiator; [0008] 2 reacting
this free radical by abstracting a halogen atom from a halogen
containing reactive substrate to form a reactive substrate free
radical; [0009] 3 reacting monomer with the reactive substrate free
radical in a free radical chain extension reaction; [0010] 4
carrying out further free radical chain extension reactions with
monomer to form a polymer or copolymer chain, particularly one
having a desired statistical number of monomer units; and [0011] 5
reacting the polymer or copolymer chain with an allylic halogen
substituted chain termination agent to terminate
polymerisation.
[0012] The invention includes a catalyst system for polymerising
ethylenically unsaturated monomers which is a combination of a
manganese carbonyl radical initiator, a halogen containing reactive
substrate and an allylic halogen substituted chain termination
agent.
[0013] The terms "catalyst system", "catalyst" and "catalytic" are
used to refer to the combination of the manganese carbonyl radical
initiator, the reactive substrate and the chain termination agent
and possibly also the individual components of this combination as
the combination has a major influence on the polymerisation
reaction even though the combination is not strictly a catalyst as
the manganese component is not regenerated during the reaction and
the reactive substrate and the chain termination agent are
incorporated into the polymer.
[0014] The polymers and/or copolymers produced directly by the
polymerisation reaction of the invention have a residue of a
reactive substrate at one end of the chain and a residue of a chain
terminating agent at the other. The invention accordingly includes
a polymer or copolymer of one or more ethylenically unsaturated
monomers having at one end of the (co)polymeric chain a residue of
a reactive substrate and a residue of a chain terminating agent at
the other. In addition to their properties as (co-)polymers, such
(co-)polymers can have valuable reactivity towards other compounds
to permit further modification by reaction with the end groups,
including by reacting with pre-formed other (co-)polymeric
materials or by carrying out further polymerisation steps using one
or both end groups as starting points for further polymerisation.
The manganese carbonyl radical initiator is desirably either a
dimanganese carbonyl compound or an organo-, particularly alkyl,
manganese carbonyl compound. Such compounds include those of the
formula (I):
R.sup.1--Mn(CO).sub.n(Lig).sub.p (I)
[0015] where [0016] R.sup.1 is C.sub.1 to C.sub.30 hydrocarbyl,
particularly alkyl, e.g. C.sub.1 to C.sub.20 alkyl, especially
C.sub.1 to C.sub.6 alkyl e.g. methyl; aryl e.g. phenyl; aralkyl,
particularly C.sub.7 to C.sub.20 aralkyl, e.g. benzyl, or such
groups substituted with halogen atoms, particularly Cl or F, alkyl
groups, particularly C.sub.1 to C.sub.6 alkyl e.g. methyl, ethyl
and t-butyl, groups, alkoxy particularly C.sub.1 to C.sub.6 alkoxy
e.g. methoxy groups, or an acyl group particularly of the formula
--C(O)R.sup.2 where R.sup.2 is alkyl, particularly C.sub.1 to
C.sub.6 alkyl or aryl, particularly phenyl, which may be
substituted with halogen atoms, particularly Cl or F, alkyl groups,
particularly C.sub.1 to C.sub.6 alkyl e.g. methyl, ethyl and
t-butyl, groups alkoxy particularly C.sub.1 to C.sub.6 alkoxy e.g.
methoxy groups; or a group of the formula:
--Mn(CO).sub.n(Lig).sub.p where Lig, n and p are as defined below;
[0017] each Lig is a ligand species particularly a phosphine or
amine ligand, such as a tertiary phosphine ligand, particularly a
tri-hydrocarbyl phosphine e.g. trialkyl, particularly C.sub.1 to
C.sub.6 alkyl e.g. tri-iso-propyl or tri-n-butyl, or triphenyl
phosphine or substituted variants of such ligands; or an amine
ligand which may be primary, secondary or tertiary amine ligand
e.g. alkyl, dialkyl or trialkyl amines particularly C.sub.1 to
C.sub.6 alkyl e.g. methyl, ethyl or butyl amines, or substituted
variants such as corresponding hydroxyalkyl e.g. 2-hydroxyethyl,
amines. [0018] n is from 1 to 5; and [0019] p is from 0 to 4; such
that n+p=5.
[0020] Within formula (I) dimanganese carbonyl compounds can be
particularly suitable initiators, e.g. compounds of the formula
(Ia):
(Lig).sub.p(CO).sub.nMn--Mn(CO).sub.n(Lig).sub.p (Ia)
where Lig, p and n are as defined for formula (I), such that
p+n=5
[0021] An especially useful dimanganese carbonyl initiator is
dimanganese decacarbonyl
{Mn.sub.2(CO).sub.10=(CO).sub.5Mn--Mn(CO).sub.5=[Mn(CO).sub.5].sub.2}
and in a specific aspect, the invention includes a method and a
catalyst of the invention where the initiator is or includes
manganese decacarbonyl.
[0022] Within the ranges set out above, the values of n and p may
vary, but usually p will be 0 or 1, with n correspondingly being 5
or 4, as values of p greater than 1 are unlikely to give any
particular advantage over initiators where p is 1 and the presence
of multiple relatively bulky ligand groups will tend to make the
Mn--Mn or Mn--C bond weaker, possibly to the point where the
compound spontaneously and reversibly dissociates even under
ambient storage conditions. The presence of a ligand, "Lig", in the
initiator may provide benefit in terms of solubility or
compatibility with other components in the polymerisation system.
The use of liganded manganese species may further simplify recovery
of catalyst residues at the end of the polymerisation.
[0023] We believe that the mechanism of catalysis involves
homolysis, particularly thermolysis or photolysis, of the Mn--Mn
bond in dimanganese carbonyl initiators or the C--Mn bond in alkyl
manganese carbonyl initiators to yield a manganese carbonyl radical
generically .Mn(CO).sub.n(Lig).sub.p (where n, p and Lig are as
defined above) and which where p=0 is .Mn(CO).sub.5 e.g. where the
initiator is dimanganese decacarbonyl or an alkyl manganese
pentacarbonyl, which then abstracts a halogen atom from the
reactive substrate to generate a reactive substrate radical, which
acts as the starting point for the chain reaction leading to
polymerisation, and produces a manganese carbonyl halide. Where an
alkyl manganese carbonyl compound is used as an initiator there
will also be an alkyl radical which may also give rise to a free
radical polymerisation sequence.
[0024] The overall initial reaction sequence appears to be along
the lines (for simplicity of illustration with manganese
decacarbonyl as the initiator):
Mn.sub.2(CO).sub.10.fwdarw.2.Mn(CO).sub.5
.Mn(CO).sub.5.30 React-X.fwdarw.React.+Mn(CO).sub.5--X
React.+>C.dbd.C<.fwdarw. etc.
R.sup.1--(>C--C<).sub.n.
where X is a halogen atom, particularly chlorine or bromine; React.
is the radical derived from the reactive substrate molecule after
halogen abstraction; >C.dbd.C<represents an ethylenically
unsaturated monomer; and >C--C< a monomer residue in the
polymer chain --(>C--C<).sub.n-- having "n" repeat units.
[0025] Chain termination may occur by reaction of the chain with a
molecule of a chain termination agent:
React-(>C--C<).sub.n.+X'-CTA.fwdarw.React-(>C--C<).sub.n--CT-
A+X'
where each R.sup.1 is independently as defined above, and CTA is
the residue of a chain termination agent after removal of a halogen
atom, X'. Where the chain termination agent residue (CTA) is used
as the reactive substrate the resulting telechelic polymer is
terminated symmetrically. However the reactive substrate and the
chain termination agent can be and desirably are different and in
this case the resulting polymer will have different groups at the
chain ends. In either case the chain is terminated by a moiety
which is not derived from units of the main repeat monomer(s)
producing a telechelic polymer.
[0026] This sequence does not necessarily end the reaction as the
halogen atom radical may react to forms radicals e.g. by reacting
with reactive substrate:
X.+React-X.fwdarw.React.+X.sub.2
or by reacting with the alkene:
##STR00001##
or by reacting with a manganese carbonyl initiator:
X.+R.sup.1--Mn(CO).sub.n(Lig).sub.p.fwdarw..Mn(CO).sub.n(Lig).sub.p+R.su-
p.1X
[0027] The resulting radicals may act to start further polymer
chains. Other chain continuing reactions are also possible.
[0028] By choice of appropriate relative proportions of the
monomer, manganese carbonyl initiator, reactive substrate and chain
terminating agent, it is possible to make polymeric materials
having chain lengths typically of from 5 to 500, more usually 10 to
300 and particularly from 20 to 200, repeat units. These correspond
to approximate molecular weights for poly(methyl methacrylate) of
from 500 to 50000, more usually 1000 to 30000 and particularly from
2000 to 20000 (and correspondingly for other monomers or mixtures
of monomers). Such molecular weights are of interest to make
polymers that can have interesting surface and interfacial effects
and to make block units that can be reacted on with further
monomers or pre-formed oligomeric or polymeric blocks to form block
co-polymers.
[0029] We have found that the method of the invention can give
polymers with relatively narrow molecular weight distributions e.g.
as measured instrumentally as polydispersity (PDI). Especially
where molecular weight control is good, PDI values of from 1.1 to
1.7, particularly from 1.2 to 1.6 have been obtained.
[0030] The chain terminating agent(s) act to terminate
polymerisation of a chain, enabling statistical control of the
molecular weight of the polymer product, and is a compound
including a halogen substituted allyl group i.e.
>C.dbd.C--C-Hal; where Hal is halogen, particularly chlorine or
bromine. The allylic halogen substituted chain termination agent
can be considered as a sub-set of the group of reactive substrates.
Thus, chain termination agents can act as reactive substrates, but
other reactive substrates do not generally act as chain termination
agents. When the chain termination agent and the reactive substrate
are present as different chemical compounds, we believe that the
ease with which the relevant carbon halogen bond dissociates will
(statistically) determine which residue is the starting point for
polymerisation (see further below).
[0031] The chain terminating agent can be a simple allyl halide
such as allyl chloride or, and particularly, allyl bromide.
However, it is desirable that the molecule includes other groups(s)
which activate the carbon halogen allylic bond which can thus act
more efficiently as chain terminating agents, or provide
functionality that is desired at an end of the resultant polymeric
product chain. Accordingly, desirable chain terminating agent
include compounds of the formula (II):
Hal-CHR.sup.3--CR.sup.4.dbd.CH.sub.2 (II)
where Hal is a halogen atom, particularly chlorine or bromine; and
R.sup.3, and R.sup.4 are each independently hydrogen, or a group:
[0032] -(Link).sub.nR.sup.5, where: [0033] n is 0 or 1, [0034] Link
is a linking group, particularly an alkylene group e.g. a C.sub.1
to C.sub.12 alkylene group; or a polymeric residue derived from a
polyester, a polyurethane, a polyalkoxylate, an acrylate polymer or
copolymer, or a polysaccharide; and [0035] R.sup.5 is a halogen
atom particularly a chlorine or bromine atom, or glycidyl; an
ethylenic double bond; carbonyl; carboxyl; cyano; hydroxyl; amino
or quaternary amino or ammonium; a phosphorus containing species; a
sulphur containing species; a hydrogen bond donor or acceptor; an
aromatic ring; a heterocyclic ring; or a saccharide residue.
[0036] Desirably at least one of R.sup.3 and R.sup.4 is other than
hydrogen.
[0037] Allyl halides activated towards reactivity as chain
terminating agents in the polymerisation system can include at
least one further halogen atom e.g. as in dihalopropenes such as
2,3-dibromo- and 2,3-dichloro-propene, or a carboxylic group as in
acids or esters such as 2-bromomethyl-prop-2-enoic acid and its
alkyl esters, particularly C.sub.1 to C.sub.6 alkyl esters for
example methyl, ethyl and butyl e.g. t-butyl esters. Such compounds
appear to afford good control of molecular weight in experimental
polymer synthesis, with the molecular weight of the polymer
produced decreasing with increasing amounts of the chain
terminating agent present.
[0038] The use of chain terminating agents including an allyl
halide group leads to polymers having a terminating group including
a double bond, and the presence of double bonds has been confirmed
in experimental polymers using NMR (.sup.1H and .sup.13C) and mass
spectrometry. Although this may provide useful functionality for
further chemical modification of the polymer, it will often be
desirable to incorporate other groups in the chain terminating
residues such as are described above in connection with formula
(II). Such other groups may include reactive groups such as: [0039]
at least one further halogen atom; [0040] a glycidyl group; [0041]
at least one further ethylenic double bond; [0042] a carbonyl group
as in ketone or aldehyde functionality e.g. as in the residue
--CH.sub.2.C(O)-(hydrogen or alkyl); [0043] carboxyl as in a
carboxylic acid, anhydride, ester or carbonate group; [0044] cyano;
[0045] hydroxyl; [0046] primary, secondary or tertiary amino or
quaternary amino or ammonium; [0047] phosphorus containing species
such as phosphates, phosphonates, phosphites, phosphine oxides,
thiophosphates and thiophosphites; [0048] sulphur containing
species such as SR, where R is alkyl, sulphates, sulphonates,
sulphonyl groups, sulphites and thioesters; hydrogen bond donors
and acceptors, particularly based on coupled donor acceptor
pairings, especially between C.dbd..H--N, C.dbd.O.H--O, O--H.N<
or N--H.N< (in which the N may be in a ring which may be
aromatic), which may be considered as synthetic mimics of the
hydrogen bond donors and acceptors in nucleic acids such as DNA and
RNA; [0049] aromatic rings such as phenyl or substituted phenyl,
particularly halogen e.g. fluorine, or vinyl substituted phenyl;
[0050] heterocyclic rings such as pyrrolidone or pyrazoline rings;
or [0051] a saccharide, particularly a sugar, residue such as a
glucosyl, sorbityl or mannosyl group.
[0052] The main reason for including such reactive atoms or groups
in the chain terminating agent is to enable such groups to be used,
after polymerisation according to the invention, in coupling
reactions with other groups, so as to enable the formation of block
copolymers. The block copolymers can be formed directly by
reactions with materials containing polymeric groups, or indirectly
by reaction with a group which includes a centre that can then be
the basis for further polymerisation.
[0053] Another approach to this is to link a preformed polymeric
fragment to the chain terminating agent so as to form a copolymer
during the polymerisation reaction of the invention. Examples of
polymeric residues that can be used in this way include residues
of: [0054] polyesters such as polyterephthalates, particularly
polyethylene terephthalate, polyhydroxyacids, such as
polyhydroxystearic acid or polylactic acid, and polylactones such
as polycaprolactone; [0055] polyalkoxylates such as polyethylene
glycol (PEG) or polypropylene glycol (PPG); [0056] polyurethanes
such as those based on the reactions between toluene di-isocyanate
or methylene diphenyldilsocyanate and polyols such as polyalkylene
polyols e.g. PEG or PPG; [0057] vinylic polymers such as acrylate
polymers such as polymethyl methacrylate (PMMA) and copolymers,
particularly including residues of other (meth)acrylate esters or
polystyrene; or [0058] polysaccharides, such as dextrins and
starches.
[0059] It is further possible to provide such polymeric residues
which Include reactive groups such as those described above, so as
to enable further reaction with polymeric species or as a growth
point for further polymerisation. Such groups are referred as
reactable macromers.
[0060] It is not clear precisely why the chain termination agents
act to control molecular weight, but is seems likely that the
allylic grouping, particularly if activated by another electron
withdrawing substituent acts to make the molecule preferentially
reactive towards the radicals at the end of the growing polymer
chains. This effect appears to be more significant in chain
termination as compared with the higher radical reactivity of
(other) reactive substrates arising from a lower carbon-halogen
bond dissociation energy (see further below). Generally, It is
desirable that the reactive substrate and the chain termination
agent are different compounds and accordingly, the invention
specifically includes a method of polymerisation of ethylenically
unsaturated monomers and a catalyst system for polymerising
ethylenically unsaturated monomers of the invention, in which the
halogen containing reactive substrate is not an allylic halogen
substituted chain termination agent.
[0061] The halogen containing reactive substrate is the starting
point for the polymerisation chain reaction so the residue of the
reactive substrate provides one terminating group in the product
polymer. The reactive substrates are compounds with activated
carbon-halogen bonds and this includes the compounds described
above as chain terminating agents as well as other halogen
containing compounds. Particularly where it is desired to make a
telechelic polymer having differing end groups, it is desirable to
choose as the reactive substrate one which is significantly more
active towards radical formation with the Mn species than chain
terminating agents generally are. In this case, it is desirable to
use a reactive substrate which has a carbon-halogen bond having a
relatively low dissociation energy. Such reactive substrates can be
termed "activated reactive substrates" to distinguish them from
reactive substrates that can also act as chain terminating agents.
Generally, activated reactive substrates are compounds having at
least one carbon halogen bond with a dissociation energy of less
than 400, more usually less than 350, and desirably less than 300,
kJ.mol.sup.-1. A range of activated reactive substrates and the
approximate respective bond dissociation energies are set out in
the following table:
TABLE-US-00001 Dissociation Compound Bond Energy (kJ mol.sup.-1)
bromotrichloromethane Br--CCl.sub.3 234 carbon tetrabromide
Br--CBr.sub.3 235 benzyl bromide Br--CH.sub.2Phenyl 241 carbon
tetrachloride Cl--CCl.sub.3 295 benzyl chloride Cl--CH.sub.2Phenyl
302
[0062] Examples of activated reactive substrates include: [0063]
halogen substituted alkanes, particularly with multiple halogen
substitution e.g. carbon tetrachloride, carbon tetrabromide,
chlorotribromomethane, trichloro- and tribromo-methanes and
dichloro- and dibromo-methanes, corresponding longer chain
haloalkanes such as C.sub.2 to C.sub.61,1-dichloro- and
dibromo-alkanes and 1,1,1-trichloro- and tribromo-alkanes e.g.
dichloro-, dibromo-, trichloro- and tribromo-ethanes; [0064]
halogen substituted alcohols, acids and esters such as
2,2-dichloro-, 2,2-dibromo, 2,2,2-trichloro- and
2,2,2-tribromoethanol, trichloroacetic acid and its alkyl,
particularly C.sub.1 to C.sub.6 alkyl esters for example methyl,
ethyl and butyl esters; [0065] halogen substituted carboxylic acid
esters such as alkyl, e.g. C.sub.2 to C.sub.6 alkyl, particularly
ethyl, 2-bromo-2-methyl propionates; [0066] aromatic substituted
alkyl (aralkyl) halides such as benzyl halides e.g. benzyl
chloride, bromide or iodide and, 2-halo-2-phenylethanes such as
2-bromo-2-phenylethane; [0067] ring substituted benzyl halides such
as alkyl substituted benzyl halides, particularly 4-alkyl benzyl
halides, in particular where the alkyl group is a C.sub.1 to
C.sub.6 alkyl, particularly methyl, ethyl and butyl e.g. t-butyl
alkyl group, or halogen substituted, particularly 4-substituted
benzyl halides such as 4-fluoro (or chloro) benzyl bromide (or
chloride), or bis-haloalkyl substituted benzenes such as
1,2-di(bromomethyl)benzene; [0068] sulphonyl chlorides such as
benzene and toluene sulphonyl chlorides.
[0069] Although, reactive substrates can act efficiently to
initiate polymerisation, activated reactive substrates do not
appear to be effective in chain termination. Thus using such
halides e.g. carbon tetrachloride, without a chain termination
agent gives efficient but uncontrolled polymerisation, typically
yielding polymer having a molecular weight greater than 70000.
[0070] Where an organic halide reactive substrate is used in
combination with a chemically different chain terminating agent the
resulting polymer will be telechelic with differing end groups.
[0071] The ethylenically unsaturated monomer can, in principle, be
any ethylenically unsaturated monomer. However, the invention is
particularly applicable to making polymers from acrylic monomers or
mixtures including a substantial proportion of acrylic monomers for
example at least 25 mole %, more usually at least 40 mole %,
commonly at least 50 mole % and potentially at least 75 mole % e.g.
up to 100 mole % of acrylic monomers. Suitable acrylic monomers
include those of the formula (IV):
R.sup.10--CR.sup.11.dbd.CR.sup.12--COR.sup.13 (IV)
where [0072] R.sup.10 is methyl or, and desirably, hydrogen; [0073]
R.sup.11 is methyl or, and desirably, hydrogen; [0074] R.sup.12 is
methyl or hydrogen; provided that at least one of R.sup.11 and
R.sup.12 is hydrogen, and [0075] R.sup.13 is --OR.sup.14, or
--NR.sup.15R.sup.16 where R.sup.14, R.sup.15 and R.sup.16 are each
hydrogen, hydrocarbyl, particularly C.sub.1 to C.sub.20, more
usually a C.sub.1 to C.sub.8, alkyl, C.sub.2 to C.sub.8
hydroxyallyl, or a polyalkyleneoxy, particularly a polyethyleneoxy
or polypropyleneoxy or a (random or block)
co-poly(ethyleneoxy)(propyleneoxy) chain, desirably containing from
2 to 50 alkyleneoxy residues, and which may be H or alkyl, usually
C.sub.1 to C.sub.4 alkyl terminated.
[0076] When the R.sup.14 is hydrogen, the carboxyl group in a
product polymer may be neutralised with cation, usually an alkali
metal or ammonium or amine, including quaternary amine. Examples of
such acrylic monomers include acrylate and methacrylate esters,
particularly alkyl, desirably C.sub.1 to C.sub.10 alkyl, esters,
especially methyl methacrylate, or polyalkyleneoxy e.g. alkyl,
particularly C.sub.1 to C.sub.4 alkyl, especially methyl capped
polyethyleneoxy, esters; acrylic and methacrylic acids, which can
be in the form of salts, especially when neutralised after
polymerisation; acrylic and methacrylic amides; and sulphonated
acrylic monomers, particularly acrylamido methyl propyl sulphonate
(AMPS) and acrylic or methacrylic acid isethionate.
[0077] Other ethylenically unsaturated monomers include vinyl
monomers such vinyl halides especially vinyl chloride, vinyl
aromatic monomers such as styrene, .alpha.-methyl styrene or vinyl
toluene, vinyl caprolactone, vinyl caprolactam and N-vinyl
pyrrolidone. The monomers can be polymerised to form telechelic
homopolymeric or copolymeric materials.
[0078] The amount of initiator used will depend on the reactivity
of the monomer(s) being polymerised and on the desired molecular
weight. Typically the molar ratio of initiator to ethylenically
unsaturated monomer will be from 1:500 to 1:10, more usually from
1:100 to 1:20, and commonly about 1:50. The relative molar
proportion of reactive substrate to initiator will usually be from
0.5:1 to 10:1, more usually from 0.7:1 to 1:7 and commonly from 1:1
to 5:1. The molar ratio of chain terminating agent to reactive
substrate, particularly an activated reactive substrate, will
usually be from 5:1 to 1:2, more usually from 3:1 to 1:1.5 and
commonly from 2:1 to 1:1.
[0079] The mechanism of the polymerisation reaction is believed, as
explained above, to involve the free radicals from homolysis of the
manganese carbonyl initiator which then react with the reactive
substrate to form radicals which react with monomer to make polymer
until polymerisation is terminated by reaction with a chain
terminating agent. Generally it is usual to have all the catalyst
components, manganese carbonyl initiator, reactive substrate and
chain terminating agent present simultaneously with the monomer at
the start of reaction. However, the free radicals are believed to
have a long enough life to permit running the polymerisation in
sequence e.g. by making the manganese carbonyl radical(s) and
possibly also the radicals derived from the reactive substrate
separately from the polymerisation reaction. Thus the manganese
carbonyl initiator and reactive substrate can be mixed, homolysis
of the manganese carbonyl initiator started and monomer added
somewhat later, though not usually after the monomer is included in
the reaction mixture. Conveniently this could be arranged as a
continuous reaction e.g. by feeding monomer into a stream
containing manganese carbonyl initiator and reactive substrate
downstream of where homolysis of the manganese carbonyl initiator
is started for example by having a heated zone or by exposure to
suitably energetic radiation, most usually UV or visible light. The
chain terminating agent could be included from the start or
probably more conveniently fed in with the monomer.
[0080] We have found that the rate of reaction, particularly where
the monomers are acrylic monomers, can be adjusted by including a
Lewis acid, particularly a metal containing Lewis acid, in the
reaction medium. The reason for the effect of Lewis acids is not
clear but we believe that, for metal containing Lewis acids, the
metal atoms in the Lewis acids can coordinate with the carbonyl
groups on acrylic monomers and activate them towards
polymerisation, leading to faster reaction and/or higher
conversion. Lewis acids having small electronegative ligands such
as halide e.g. chlorine or bromine, and/or including metals with
occupied higher, particularly d or f, orbitals, more particularly
transition metals having an atomic number of at least 30 (zinc),
appear to be more effective in accelerating the reaction. Examples
of useful Lewis acids include those based on magnesium e.g.
magnesium halides such as magnesium bromide or magnesium chloride,
zinc e.g. zinc halides, such as zinc bromide or zinc chloride, and
salts such as zinc trifluoromethane-sulfonate (usually shortened to
"triflate"--commonly abbreviated "Tf"), lanthanum salts such as
lanthanum acetate, particularly as the heptahydrate, ytterbium
salts such as the halides, particularly ytterbium chloride e.g. as
the trihydrate, or triflate. Among these zinc chloride seem to be
particularly effective. The beneficial effects on the speed of
reaction or higher conversion may be linked with a slight
broadening of the molecular weight distribution, but without
detrimental effect on the control of molecular weight.
[0081] The temperature of reaction may depend on how homolysis of
the manganese carbonyl radical initiator is carried out. Where
radical formation is prompted by thermolysis, the polymerisation
reaction will generally be carried out at a temperature
sufficiently high that thermolysis of the relevant Mn--Mn or Mn--C
bond readily takes place, typically at least 50.degree. C. and up
to 150.degree. C., e.g. up to 120.degree. C. particularly up to
100.degree. C., and usually from 50 to 70.degree. C. Within these
temperature ranges we have found that the rate of reaction
increases with temperature. Thus, we have found, experimentally,
that increasing the temperature from 70.degree. C. to 100.degree.
C. gave an increase in the relative rate of polymerisation of about
2.5 (2.7 check). Where radical formation is prompted by photolysis,
the polymerisation reaction can be carried out at ambient, sub- or
super-ambient temperatures, usually in the range 50 to 100.degree.
C. more usually -10 to 70.degree. C. e.g. 50 to 70.degree. C. or
-10 to 10.degree. C. The use of lower temperatures may aid control
of the polymerisation e.g. by suppressing side reactions especially
where the reactive substrate and/or chain terminating agent include
reactive substituents.
[0082] The manganese carbonyl radical initiator compounds (and
manganese halide catalyst residues) are sensitive to oxidation e.g.
by atmospheric oxygen, so the reaction will typically be carried
out in a suitably inert atmosphere for example (oxygen free)
nitrogen, argon or carbon dioxide. Further, reagents and solvents
will also be used in forms that do not add reactive oxygen to the
reaction system, for example by ensuring that solvents are
degassed/deoxygenated before use. Suitable solvents and diluents
for the free radical polymerisation reaction include aromatic
solvents such as toluene or xylene; halogenated solvents such as
dichloromethane; alcohols such as iso-propanol; glycols such as
monoethylene glycol and monopropylene glycol; ethers such as
tetrahydrofuran; dialkyl ketones such as methyl ethyl ketone;
lactones such as butyrolactone; dipolar aprotic solvents such as
dimethyl formamide and dimethyl sulphoxide.
[0083] The concentrations of the reaction components can be those
convenient according to the solubility of the components,
particularly the monomer in the reaction medium or any solvent or
diluent used. When aromatic solvents, such as toluene, are used for
polymerising acrylic or largely acrylic monomers, the concentration
of monomer can be from 5 to 80%, usually 10 to 70, more usually 20
to 40%, and typically about 25%, w/w of the monomer solvent
mix.
[0084] Such concentrations generally correspond to a monomer
molarity (based on the molecular weight of methyl methacrylate) of
from 0.5 to 7, more usually 2 to 4 and typically about 2.5, molar.
Corresponding amounts of the catalyst components will be used e.g.
within the respective ratios and ranges given above. Thus, in a
reaction where all the catalyst components are present with the
monomer, for a 2.5 molar solution of methyl methacrylate, the
concentration of the catalyst components will typically be, for the
manganese carbonyl initiator e.g. dimanganese decacarbonyl, from
0.005 to 0.3, more usually from 0.01 to 0.1, e.g. about 0.044,
molar, reactive substrate from 0.002 to 0.25, more usually from
0.05 to 0.2, and particularly from 0.04 to 0.15 molar, and chain
terminating agent from 0.002 to 0.25, more usually from 0.05 to
0.2, and particularly from 0.04 to 0.15 molar.
[0085] Generally the polymerisation reaction will be carried out at
ambient pressure. However, particularly if volatile or gaseous
monomers are used, the pressure may be superambient e.g. up to 100
Bar (10 MPa).
[0086] It is likely that the presence of manganese carbonyl
Initiator catalyst residues, particularly as active catalyst, in
the product polymer will be undesirable. Thus, the manganese
carbonyl initiator in the reaction mix will usually be deactivated
and desirably manganese residues removed from the reaction mix, at
the end of the polymerisation reaction. The manganese carbonyl
initiator can be inactivated by oxidation, for example by exposure
to air, and the manganese oxide(s) resulting can be removed e.g. by
filtration.
[0087] Polymer product can be separated from the reaction mixture
e.g. by evaporation of volatiles or by precipitating the polymer by
adding a polymer non-solvent e.g. for acrylic polymers such as
poly(methyl methacrylate) a liquid alkane such as hexane, to the
reaction mixture.
[0088] The catalytic reaction of the invention can produce end
functionalised polymeric molecules. Such functionalised polymers
can themselves be used as building blocks to produce more complex
polymers for example ABA and ABC block copolymers, star copolymers
(dendrimers).
[0089] Block co-polymers can be made from polymers of and made by
the method of this invention by: [0090] 1 carrying out further
polymerisation using the polymer as a substrate at one or both
chain ends; or [0091] 2 by reacting the polymer with pre-formed
polymeric blocks.
[0092] Each of these methods can produce AB, ABA or ABC block
copolymers.
[0093] The invention accordingly includes a block copolymer having
a first polymer block which is the residue of a polymer of or made
by the present invention, and at least one second polymer block
covalently bound to one or both ends of the first polymer
block.
[0094] These product polymers can find applications as surfactants
particularly dispersants, antifog additives, antistatic additives,
emulsifiers or demulsifiers and personal care products foamers or
defoamers; barrier polymers; compatibilisers; blowing agents;
rheology modifiers; or gas hydrate inhibitors.
[0095] The following Examples illustrate the invention. All parts
and percentages are by weight unless otherwise stated.
Test Methods
[0096] Polymer molecular weight--the polymer number average
molecular weight was determined by gel permeation chromatography
(gpc) on a system equipped with a guard column and two Shodex
columns (KF-802.5 and KF-803) with a Waters 2410 differential
refractive index detector using THF at 1 ml.min.sup.-1 as eluent
and standardised against narrow molecular weight distribution
poly(methyl methacrylate) (PMMA) standards. [0097] Polymer
molecular weight dispersion (PDI)-- was calculated from the gpc
data. [0098] Note: This gpc method has a limit of about 25000 for
accurate molecular weight determination as at higher molecular
weights the total exclusion limit of the gpc column is exceeded.
Thus, molecular weights greater than 25000 are approximate and it
is not possible to obtain accurate values of PDI (though
approximate values could be obtained in some cases).
[0099] Polymer conversions were measured gravimetrically.
[0100] Polymer products were analysed using .sup.1H and/or .sup.13C
NMR and fast atom bombardment (FAB) mass spectrometry, particularly
for low molecular weight polymers, in particular to confirm the
presence of double bonds at one or both ends of the polymer.
[0101] Synthesis Examples SE1 to SE12 illustrate the synthesis of
the compounds of the formula (I).
SYNTHESIS EXAMPLE SE1
[0102] Methyl methacrylate was polymerised using dimanganese
decacarbonyl as the polymerisation initiator and
2,3-dibromoprop-1-ene as reactive substrate and chain terminating
agent. Methyl methacrylate (3.75 g; 4 ml; 37.5 mmol, as a 25% w/w
solution in dry degassed toluene) was added to dimanganese
decacarbonyl (0.29 g; 0.75 mmol) dissolved in dry degassed toluene
(13 ml; 11.25 g) under a nitrogen atmosphere in a Schlenk tube
(molar ratio of monomer to initiator 50:1). The tube was placed in
a thermostatted oil bath at 60.degree. C. for 1 hour and then
2,3-dibromoprop-1-ene (0.15 g; 0.75 mmol) was added using a
degassed syringe. Samples (1-2 ml) were removed at intervals for
analysis to check progress of the reaction. Conversion of the
monomer reached 32.3% after 5 hours reaction time. At the end of
the reaction time, the manganese carbonyl catalyst initiator
residues were deactivated by oxidation by exposing the reaction
mixture to air and the manganese was separated from the reaction
mixture by filtration. The polymer product was recovered by
precipitation from the reaction mixture using hexane.
SYNTHESIS EXAMPLE SE2
[0103] Example SE1 was repeated except that 2,3-dibromoprop-1-ene
was used as the reactive substrate and chain terminating agent at a
mole ratio of reactive substrate to dimanganese decacarbonyl of
2:1.
SYNTHESIS EXAMPLE SE3
[0104] Example SE1 was repeated except that the mole ratio of
2,3-dibromoprop-1-ene to dimanganese decacarbonyl was 3:1.
SYNTHESIS EXAMPLE SE4
[0105] Example SE1 was repeated except that the mole ratio of
2,3-dibromoprop-1-ene to dimanganese decacarbonyl was 4:1.
SYNTHESIS EXAMPLE SE5
[0106] Example SE1 was repeated except that 2,3-dichloroprop-1-ene
was used as the reactive substrate and chain terminating agent and
the molar amount of dimanganese decacarbonyl and
2,3-dichloroprop-1-ene used was double that used in SE1 (molar
ratio 2:2).
SYNTHESIS EXAMPLE SE6
[0107] Methyl methacrylate (37.5 mmol) was polymerised by the
method described in Example SE1 but using di[manganese
tetracarbonyl triphenylphosphine] (0.75 mmol) as the polymerisation
initiator and 2-(bromomethyl)acrylic acid (1.05 mmol) as the
reactive substrate and chain terminating agent. Conversion of the
monomer reached 80% after 70.5 hours reaction time. The
di[manganese tetracarbonyl triphenylphosphine] used as the
initiator included residual manganese decacarbonyl (from catalyst
synthesis) so molecular weight measurements (by gpc) showed a
bimodal distribution attributed to polymerisations initiated by the
two initiators.
COMPARATIVE SYNTHESIS EXAMPLE CSE1
[0108] Example SE1 was repeated except that benzyl bromide was used
instead of 2,3-dibromoprop-1-ene at a molar ratio of benzyl bromide
to dimanganese decacarbonyl of 1:1.
COMPARATIVE SYNTHESIS EXAMPLE CSE2
[0109] Example CSE2 was repeated except that the molar ratio of
benzyl bromide to dimanganese decacarbonyl was 2:1.
COMPARATIVE SYNTHESIS EXAMPLE CSE3
[0110] Example CSE2 was repeated except that carbon tetrachloride
was used instead of benzyl bromide at a molar ratio of carbon
tetrachloride to dimanganese decacarbonyl of 2:1.
COMPARATIVE SYNTHESIS EXAMPLE CSE4
[0111] Example SE1 was repeated except that ethyl
2-bromo-2-methylpropionate was used instead of
2,3-dibromoprop-1-ene at a mole ratio of ethyl
2-bromo-2-methylpropionate to dimanganese decacarbonyl of 2:1.
[0112] Reaction information and some properties of the polymers
made in Synthesis Examples SE1 to SE8 and CSE1 to CSE4 are set out
in Table 1 below.
TABLE-US-00002 TABLE 1 Reactive Substrate/ Conv Ex No Chain
Termination Agent Ratio* (%) Mn PDI SE1 2,3-dibromoprop-1-ene 1:1
40.0 ca 28000 ca 1.50 SE2 2,3-dibromoprop-1-ene 2:1 32.3 17600 1.41
SE3 2,3-dibromoprop-1-ene 3:1 26.2 12900 1.26 SE4
2,3-dibromoprop-1-ene 4:1 22.5 8900 1.23 SE5 2,3-dichloroprop-1-ene
2:2 8.5 22550 1.52 SE6 2-(bromomethyl)acrylic 1.1 58 27300 1.54
acid CSE1 benzyl bromide 1:1 83.5 >70000 -- CSE2 benzyl bromide
2:1 54.5 >70000 -- CSE3 carbon tetrachloride 2:1 48.2 >70000
-- CSE4 ethyl 2-bromo-2-methyl- 2:1 52.2 >70000 -- propionate
*molar ratio of reactive substrate/chain terminating agent to
dimanganese decacarbonyl
[0113] In Synthesis Examples SE7 to SE10, the catalyst/initiator
system includes reactive substrates and chain terminating agents
which are different compounds.
SYNTHESIS EXAMPLE SE7
[0114] Example SE2 was repeated except that carbon tetrachloride
was used as the reactive substrate and 2,3-dibromoprop-1-ene as the
chain terminating agent at a mole ratio of reactive substrate to
chain terminating agent to dimanganese decacarbonyl of 2:2:1.
SYNTHESIS EXAMPLE SE8
[0115] Example SE9 was repeated except that the mole ratio of
reactive substrate to chain terminating agent to dimanganese
decacarbonyl was 2:3:1.
SYNTHESIS EXAMPLE SE9
[0116] Example SE9 was repeated except that 2,3-dichloroprop-1-ene
was used as the chain terminating agent.
SYNTHESIS EXAMPLE SE10
[0117] Example SE11 was repeated except that the mole ratio of
reactive substrate to chain terminating agent to dimanganese
decacarbonyl was 2:31.
COMPARATIVE SYNTHESIS EXAMPLE CSE5
[0118] Example SE2 was repeated except that a combination of carbon
tetrachloride and benzyl bromide was used as the reactive substrate
at a mole ratio of carbon tetrachloride to benzyl bromide to
dimanganese decacarbonyl of 2:2:1.
COMPARATIVE SYNTHESIS EXAMPLE CSE6
[0119] Example CSE5 was repeated except that the mole ratio of
carbon tetrachloride to benzyl bromide to dimanganese decacarbonyl
was 2:3:1.
[0120] Reaction Information and some properties of the polymers
made in Synthesis Examples SE7 to SE10 and CSE5 and CSE6 are set
out in Table 2 below.
TABLE-US-00003 TABLE 2 Conv Ex No Chain terminating agent Ratio*
(%) Mn PDI SE7 2,3-dibromoprop-1-ene 2:2:1 29.0 7100 1.5 SE8
2,3-dibromoprop-1-ene 3:2:1 31.5 6600 1.45 SE9
2,3-dichloroprop-1-ene 2:2:1 38.8 10600 1.66 SE10
2,3-dichloroprop-1-ene 3:2:1 34.7 11600 1.61 CSE5 benzyl bromide
2:2:1 40.0 ca 45000 -- CSE6 benzyl bromide 2:3:1 37.2 ca 50000 --
*molar ratio of chain terminating agent to reactive substrate
(carbon tetrachloride) to dimanganese decacarbonyl.
SYNTHESIS EXAMPLE SE11
[0121] Example SE1 was repeated with minor procedural variations in
that the reagents were all mixed as a 25% w/w solution in toluene
under a nitrogen in the Schlenk tube (molar ratio of monomer:chain
terminating agent:initiator 50:3:1), degassed and then heated to
reaction temperature for 5 hours, with product recovery using
precipitation by hexane or petroleum ether (40/60.degree. C.). The
reaction was run at 60, 70, 80, 90, 110 and 120.degree. C. For runs
above 100.degree. C. a mixture of o- and p-xylene was used as the
reaction solvent. Generally the reaction ran more quickly at the
higher temperatures. The reaction conditions and the properties of
the polymers produced are set out in Table 3 below.
TABLE-US-00004 TABLE 3 Temp Time Conv Ex No (.degree. C.) (h) (%)
Mn PDI SE13.1 60 6 25 5500 1.52 SE13.2 70 5 35 7600 1.49 SE13.3 80
5 42 10200 1.27 SE13.4 90 5 66 5900 1.49 SE13.5 100 5 70 5300 1.51
SE13.6 110 5 83 3700 1.36
SYNTHESIS EXAMPLE SE12
[0122] Example SE11 was repeated except that zinc chloride
(ZnCl.sub.2) was include in the reaction mixture at a molar ratio
to dimanganese decacarbonyl of 5:1. The reaction was run at 60, 70,
80, 90, 110 and 120.degree. C. The reaction conditions and the
properties of the polymers produced are set out in Table 4
below.
TABLE-US-00005 TABLE 4 Temp. Time Conv Ex No (.degree. C.) (h) (%)
Mn PDI SE13.1 60 5.5 54 6000 1.51 SE13.2 70 5 57 6500 1.36 SE13.3
80 5 64 5700 1.42 SE13.4 90 5 88 5500 1.64 SE13.5 110 5 77 4000
1.38 SE13.6
SYNTHESIS EXAMPLE SE13
[0123] Example SE12 was repeated at a reaction temperature of
60.degree. C., but substituting various Lewis acids for the zinc
chloride at varying levels. The materials, reaction conditions and
the properties of the polymers produced are set out in Table 5
below.
TABLE-US-00006 TABLE 5 Lewis acid Time Conv Ex No nature equiv. (h)
(%) Mn PDI SE13.1 Zn(OTf).sub.2 99 76 5500 1.52 SE13.2
YbCl.sub.3.cndot.hydrate 1 99 80 7500 1.52 SE13.3
La(OAc).sub.3.cndot.7H.sub.2O 1 99 76 6700 1.60 SE13.4
Sc(OTf).sub.3 1 93 80 5600 1.50 SE13.5 Sc(OTf).sub.3 5 28 39 3200
1.16 SE13.6 Yb(OTf).sub.3 5 45 97 7300 1.40 SE13.7 MgBr.sub.2 5 28
79 6500 1.73 SE13.8 ZnCl.sub.2 5 23 99 4600 1.51
* * * * *