U.S. patent application number 11/395882 was filed with the patent office on 2006-08-10 for telechelic alkadiene polymers with crosslinkable end groups and methods for making the same.
This patent application is currently assigned to California Institute of Technology. Invention is credited to Robert H. Grubbs, Bob R. Maughon, Takeharu Morita.
Application Number | 20060178493 11/395882 |
Document ID | / |
Family ID | 26762597 |
Filed Date | 2006-08-10 |
United States Patent
Application |
20060178493 |
Kind Code |
A1 |
Maughon; Bob R. ; et
al. |
August 10, 2006 |
Telechelic alkadiene polymers with crosslinkable end groups and
methods for making the same
Abstract
The present invention relates to telechelic polymers having
crosslinkable end groups of the formula ##STR1## and methods for
preparing the same wherein n is an integer; ##STR2## is an
alkadienyl group; Y is an alkyl group; and Z is crosslinkable end
group. In general, the inventive synthesis involves reacting a
functionalized chain transfer agent having crosslinkable ends with
a cycloalkene in the presence of a ruthenium or osmium catalyst of
the formula ##STR3## wherein: M is ruthenium or osmium; X and
X.sup.1 are independently any anionic ligand; L and L.sup.1 are any
neutral electron donor ligand; R and R.sup.1 are each hydrogen or a
substituted or unsubstituted substituent wherein the substituent is
selected from the group consisting of C.sub.1-C.sub.20 alkyl,
C.sub.2-C.sub.20 alkenyl, C.sub.2-C.sub.20 alkynyl, aryl,
C.sub.1-C.sub.20 carboxylate, C.sub.1-C.sub.20 alkoxy,
C.sub.1-C.sub.20 alkenyloxy, C.sub.2-C.sub.20 alkynyloxy, aryloxy,
C.sub.2-C.sub.20 alkoxycarbonyl, C.sub.1-C.sub.20 alkylthio,
C.sub.1-C.sub.20 alkylsulfonyl and C.sub.1-C.sub.20 alkylsulfinyl.
In another aspect of the invention, methods for controlling the
molecular weight of the resulting telechelic polymer are also
presented.
Inventors: |
Maughon; Bob R.; (Midland,
MI) ; Morita; Takeharu; (Osaka, JP) ; Grubbs;
Robert H.; (Pasadena, CA) |
Correspondence
Address: |
MINTZ, LEVIN, COHN, FERRIS, GLOVSKY AND POPEO, P.C
1400 PAGE MILL ROAD
PALO ALTO
CA
94304-1124
US
|
Assignee: |
California Institute of
Technology
Pasadena
CA
|
Family ID: |
26762597 |
Appl. No.: |
11/395882 |
Filed: |
March 31, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11064033 |
Feb 22, 2005 |
7022789 |
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11395882 |
Mar 31, 2006 |
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10151757 |
May 21, 2002 |
6867274 |
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11064033 |
Feb 22, 2005 |
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09271348 |
Mar 17, 1999 |
6465590 |
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10151757 |
May 21, 2002 |
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60079949 |
Mar 30, 1998 |
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Current U.S.
Class: |
526/264 ;
524/333; 526/171; 526/269; 526/270; 526/276; 526/308; 526/319;
526/329; 526/336; 526/339 |
Current CPC
Class: |
C08F 36/20 20130101;
C08L 19/006 20130101; C08F 36/20 20130101; C08F 2/38 20130101; C08L
53/02 20130101; C08F 290/06 20130101; C08L 53/02 20130101; C08L
2666/02 20130101; C08F 4/26 20130101; C08L 2666/14 20130101; C08F
4/80 20130101; C08F 290/14 20130101; C08F 2/38 20130101; C08G 59/00
20130101; C08F 36/20 20130101; C08G 61/08 20130101; C08F 36/20
20130101; C08L 53/02 20130101 |
Class at
Publication: |
526/264 ;
526/269; 526/270; 526/276; 524/333; 526/336; 526/339; 526/308;
526/329; 526/319; 526/171 |
International
Class: |
C08F 26/08 20060101
C08F026/08 |
Claims
1. A method for synthesizing a polymer of the formula ##STR29##
comprising contacting a cycloalkene with a initiator of the formula
##STR30## in the presence of a chain transfer agent of the formula
Z--Y.dbd.Y--Z wherein: n is an integer; --Y.dbd.Y-- is an alkenyl
group; Z is a crosslinkable group; M is ruthenium or osmium; X and
X.sup.1 are independently any anionic ligand; L and L.sup.1 are any
neutral electron donor ligand; and R and R.sup.1 are each hydrogen
or a substituent group selected from the group consisting of
C.sub.1-C.sub.20 alkyl, C.sub.2-C.sub.20 alkenyl, C.sub.2-C.sub.20
alkynyl, aryl, C.sub.1-C.sub.20 carboxylate, C.sub.1-C.sub.20
alkoxy, C.sub.2-C.sub.20 alkenyloxy, C.sub.2-C.sub.20 alkynyloxy,
aryloxy, C.sub.2-C.sub.20 alkoxycarbonyl, C.sub.1-C.sub.20
alkylthio, C.sub.1-C.sub.20 alkylsulfonyl and C.sub.1-C.sub.20
alkylsulfinyl, the substituent group optionally substituted with
one or more moieties selected from the group consisting of
C.sub.1-C.sub.5 alkyl, C.sub.1-C.sub.5 alkoxy, aryl and a
functional group wherein the functional group is selected from the
group consisting of hydroxyl, thiol, thioether, ketone, aldehyde,
ester, ether, amine, imine, amide, nitro, carboxylic acid,
disulfide, carbonate, isocyanate, carbodiimide, carboalkoxy,
carbamate, and halogen.
2. The method of claim 1, wherein: M is ruthenium; X and X.sup.1
are each halide; L and L.sup.1 each a phosphine of the formula
PR.sup.3R.sup.4R.sup.5, where R.sup.3, R.sup.4, and R.sup.5 are
each independently aryl or C.sub.1-C.sub.10 alkyl; R is hydrogen;
and, R.sup.1 is phenyl or vinyl, optionally substituted with one or
more moieties selected from the group consisting of C.sub.1-C.sub.5
alkyl, C.sub.1-C.sub.5 alkoxy, phenyl, and a functional group
selected from the group consisting of chloride, bromide, iodide,
fluoride, --NO.sub.2, --NMe.sub.2, methyl, methoxy and phenyl.
3. The method of claim 2, wherein: X and X.sup.1 are each chloride;
L and L.sup.1 are each selected from the group consisting of
--P(cyclohexyl).sub.3, --P(cyclopentyl).sub.3,
--P(isopropyl).sub.3, and P(phenyl).sub.3; and, R is phenyl.
4. The method of claim 1, wherein the cycloalkene is selected from
the group consisting of norbornene, norbornadiene, cyclopentene,
dicyclopentadiene, cyclo-octene, 7-oxanorbornene,
7-oxanorbornadiene, cyclodocene, 1,3-cyclooctadiene,
1,5-cyclooctadiene, 1,3-cycloheptadiene, and derivatives
thereof.
5. The method of claim 1, wherein the cycloalkene is a
cycloalkadiene.
6. The method of claim 1, wherein --Y.dbd.Y-- is a C.sub.2-C.sub.20
alkene and Z is selected from a group consisting of methacrylate,
acylate, cinnainate, epoxide, lactone, cyclic carbonate,
tetrahydrofuran, oxetane, lactam, phosphazene, and
alkoxysilane.
7. The method of claim 6, wherein --Y.dbd.Y-- is a C.sub.2-C.sub.10
alkene and Z is methacrylate or epoxide.
8. The method of claim 7, wherein the cycloalkene is cyclooctadiene
and Z--Y.dbd.Y-- Z is cis-2-butene-1,4-diol dimethacrylate or
cis-2-butene-1,4-diol diglycidyl ether.
9. A method for synthesizing a polymer of the formula ##STR31##
comprising contacting a cycloalkene with an initiator of the
formula ##STR32## in the presence of a chain transfer agent of the
formula ##STR33## wherein: n is an integer; --Y.dbd.Y-- is an
alkenyl group; Z is a crosslinkable group; M is ruthenium; X and
X.sup.1 are each halide; L and L.sup.1 each a phosphine of the
formula PR.sup.3R.sup.4R.sup.5, where R.sup.3, R.sup.4, and R.sup.5
are each independently aryl or C.sub.1-C.sub.10 alkyl; R
substituent is hydrogen; and, R.sup.1 is phenyl or vinyl,
optionally substituted with one or more moieties selected from the
group consisting of C.sub.1-C.sub.5 alkyl, C.sub.1-C.sub.5 alkoxy,
phenyl, and a functional group selected from the group consisting
of chloride, bromide, iodide, fluoride, --NO.sub.2, --NMe.sub.2,
methyl, methoxy and phenyl.
10. The method of claim 9, wherein: X and X.sup.1 are each
chloride; L and L.sup.1 are each selected from the group consisting
of --P(cyclohexyl).sub.3, --P(cyclopentyl).sub.3,
--P(isopropyl).sub.3, and --P(phenyl).sub.3; and, R is selected
from the group consisting of phenyl, CH.dbd.CPh.sub.2 and
CH.dbd.C(CH.sub.3).sub.2.
11. The method of claim 10, wherein the cycloalkene is selected
from the group consisting of norbornene, norbornadiene,
cyclopentene, dicyclopentadiene, cyclo-octene, 7-oxanorbornene,
7-oxanorbornadiene, cyclodocene, 1,3-cyclooctadiene,
1,5-cyclooctadiene, 1,3-cycloheptadiene, and derivatives
thereof.
12. The method of claim 10, wherein the cycloalkene is a
cycloalkadiene.
13. The method of claim 12, wherein the cycloalkadiene is selected
from the group consisting of norbornadiene, dicyclopentadiene,
1,3-cyclooctadiene, 1,5-cyclooctadiene, 1,3-cycloheptadiene, and
derivatives thereof.
14. The method of claim 9, wherein Z is selected from the group
consisting of methacrylate, acylate, cinnamate, epoxide, lactone,
cyclic carbonate, tetrahydrofuran, oxetane, lactam, phosphazene,
and trialkoxysilane.
15. The method of claim 12, wherein ##STR34## is
cis-2-butene-1,4-diol dimethacrylate or cis-2-butene-1,4-diol
diglycidyl ether.
16. The method of claim 15, wherein the cycloalkadiene is
cyclooctadiene.
17. A method for synthesizing a polymer of the formula ##STR35##
comprising reacting ##STR36## with an initiator of the formula
##STR37## in the presence of a chain transfer agent of the formula
##STR38## wherein: n is an integer; Z is a crosslinkable group; M
is ruthenium; X and X.sup.1 are each chloride; L and L.sup.1 are
each selected from the group consisting of --P(cyclohexyl).sub.3,
--P(cyclopentyl).sub.3, --P(isopropyl).sub.3, and
--P(phenyl).sub.3; R substituent is hydrogen; and, R.sup.1 is
phenyl or vinyl, optionally substituted with one or more moieties
selected from the group consisting of C.sub.1-C.sub.5 alkyl,
C.sub.1-C.sub.5 alkoxy, phenyl, and a functional group selected
from the group consisting of chloride, bromide, iodide, fluoride,
--NO.sub.2, --NMe.sub.2, methyl, methoxy and phenyl.
18. The method of claim 17, wherein R is phenyl, CH.dbd.CPh.sub.2,
or CH.dbd.C(CH.sub.3).sub.2.
19. The method of claim 18, wherein Z is selected from the group
consisting of methacrylate, acylate, cinnamate, epoxide, lactone,
cyclic carbonate, tetrahydrofuran, oxetane, lactam, phosphazene,
and alkoxysilane.
20. The method of claim 19, wherein Z is ##STR39##
21. A method for controlling the molecular weight of a telechelic
polymer synthesized using a ring-opening polymerization reaction of
a cycloalkene and a ruthenium metathesis initiator in the presence
of a functionalized chain transfer agent comprising modulating the
ratio of the concentration of the cycloalkene to the concentration
of the chain transfer agent.
22. The method of claim 21, wherein the cycloalkene is a
cycloalkadiene selected from the group consisting of norbornadiene,
dicyclopentadiene, 1,3-cyclooctadiene, 1,5-cyclooctadiene,
1,3-cycloheptadiene, and derivatives thereof.
23. The method of claim 22, wherein the functionalized chain
transfer agent is of the formula ##STR40## wherein Z is a
crosslinkable end group selected from the group consisting of
methacrylate, acylate, cinnamate, epoxide, lactone, cyclic
carbonate, tetrahydrofuran, oxetane, lactam, phosphazene, and
alkoxysilane.
24. The method of claim 21, wherein the ruthenium metathesis
initiator is of the formula ##STR41## wherein Cy is cyclohexyl or
cyclopentyl; R is hydrogen; and, R.sup.1 is phenyl,
CH.dbd.CPh.sub.2, or CH.dbd.C(CH.sub.3).sub.2.
25. A method for preparing crosslinked polymers comprising:
contacting a cycloalkene with an initiator of the formula ##STR42##
in the presence of a chain transfer agent of the formula ##STR43##
to make a polymer of the formula ##STR44## and treating the polymer
with a crosslinking agent wherein: n is an integer; Z is a
crosslinkable group selected from a group consisting of
methacrylate, acylate, cinnamate, epoxide, lactone, cyclic
carbonate, tetrahydrofuran, oxetane, lactam, phosphazene, and
alkoxysilane; Cy is cyclohexyl or cyclopentyl; R is hydrogen; and
R.sup.1 is phenyl, CH.dbd.CPh.sub.2, or
CH.dbd.C(CH.sub.3).sub.2.
26. The method of claim 25, wherein Z is ##STR45## and the
crosslinking agent is heat in combination with benzoyl
peroxide.
27. The method of claim 25, wherein Z is ##STR46## and the
crosslinking agent is light in combination with benzoyl peroxide or
2,2-dimethoxy-2-phenylacetophenone.
28. The method of claim 25, wherein Z is ##STR47## and the
crosslinking agent is H.sub.2SO.sub.4.
29. A linear polymer of the general formula ##STR48## wherein: n is
an integer; ##STR49## is an alkadienyl group; Y is an alkyl group;
and, Z is a crosslinkable end group.
30. The polymer of claim 29, wherein: ##STR50## is a
C.sub.4-C.sub.20 alkadienyl group; Y is a C.sub.1-C.sub.10 alkyl;
and Z is selected from the group consisting of methacrylate,
acylate, cinnamate, epoxide, lactone, cyclic carbonate,
tetrahydrofuran, oxetane, lactams, phosphazenes, and
alkoxysilanes.
31. The polymer of claim 29, having the formula ##STR51##
32. The polymer of claim 29, having the formula ##STR52##
33. The polymer of claim 31, wherein Z is methacrylate or
epoxide.
34. The polymer of claim 32, wherein Z is methacrylate or epoxide.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 11/064,033, filed Feb. 22, 2005, now allowed,
which is a continuation of U.S. patent application Ser. No.
10/151,757, filed May 21, 2002, now U.S. Pat. No. 6,867,274, which
is a divisional of U.S. patent application Ser. No. 09/271,348
filed Mar. 17, 1999, now U.S. Pat. No. 6,465,590. Priority under 35
U.S.C. .sctn.119(e)(1) to Provisional U.S. Pat. Application Ser.
No. 60/079,949, filed Mar. 30, 1998 is claimed. The disclosures of
the aforementioned applications are incorporated by reference in
their entireties.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] The U.S. Government has certain rights in this invention
pursuant to Grant No. CHE-9509745 awarded by the National Science
Foundation.
TECHNICAL FIELD
[0003] The present invention relates to telechelic polymers and
methods for making the same. More particularly, the present
invention relates to telechelic polymer segments of controlled
molecular weight having crosslinkable end groups and methods for
preparing the same.
BACKGROUND OF THE INVENTION
[0004] Telechelic polymers can be simply defined as polymers that
bear reactive functional groups at their chain termini. The
interest in these polymeric materials is derived from the fact that
through these reactive end groups, a vast number of macromolecular
materials can be prepared. Telechelic polymers have found
application in the synthesis of block copolymers, star polymers,
crosslinked polymer networks, and ionic polymer networks. Low
molecular weight liquid telechelic polymers have been successfully
used in reaction injection molding, and the formation of ABA
triblock and multiblock copolymers via telechelic polymers has
dramatically impacted the development of thermoplastic elastomers.
Based on these numerous valuable applications, considerable
research efforts have been devoted to improving the synthesis of
telechelic polymers.
[0005] The development of telechelic polymers with crosslinkable
end groups such as methacrylate or epoxide groups is of interest
for the preparation of interpenetrating polymer networks, AB
crosslinked polymeric materials, more thermally and chemically
resistant materials, and for the immobilization of biomaterials.
However, these reactive end groups have been typically incorporated
through a post-polymerization transformation due to the instability
of these functional groups to tolerate many of the typical
conditions associated with polymerization reactions.
[0006] Recently, a non-metathesis-mediated polymer degradation
approach was applied to polymers derived from ROMP.
Copolymerization of cyclooctadiene ("COD") with either
cis-4,7-dihydro-1,3-dioxepan (1) or
cis-4,7-dihydro-2-phenyl-1,3-dioxepan (2) using well-defined
ruthenium-based metathesis initiators,
(PCy.sub.3)Cl.sub.2Ru.dbd.CHR' (wherein R'.dbd.Ph (3), or wherein
R'.dbd.(CH.dbd.CPh.sub.2) (4)), resulted in a polymer bearing both
poly(butadiene) and acetal units along the backbone. Subsequent
acid hydrolysis of these acetal units resulted in the desired
hydroxytelechelic poly(butadiene) ("HTPBD") oligomers in moderate
yields. Although this method proved to be successful for the
synthesis of HTPBD, this method is not generally applicable for the
preparation of telechelic polymers with other functional end
groups.
[0007] As a result, a need exists for methods for synthesizing
telechelic polymers having a variety of end groups, particularly
crosslinkable end groups and which do not require
post-polymerization transformations for polymer
functionalization.
SUMMARY OF THE INVENTION
[0008] The present invention relates to telechelic polymers having
crosslinkable end groups of the formula ##STR4## and methods for
preparing the same wherein n is an integer; ##STR5## is an
alkadienyl group; Y is an alkyl group; and Z is a crosslinkable end
group. In general, the inventive synthesis involves reacting a
chain transfer agent having crosslinkable end groups with a
cycloalkene in the presence of a ruthenium or osmium initiator of
the formula ##STR6## wherein: [0009] M is ruthenium or osmium;
[0010] X and X.sup.1 are independently any anionic ligand; [0011] L
and L.sup.1 are any neutral electron donor ligand; [0012] R and
R.sup.1 are each hydrogen or a substituted or unsubstituted
substituent wherein the substituent is selected from the group
consisting of C.sub.1,-C.sub.20 alkyl, C.sub.2-C.sub.20 alkenyl,
C.sub.2-C.sub.20 allcynyl, aryl, C.sub.1-C.sub.20 carboxylate,
C.sub.1-C.sub.20 alkoxy, C.sub.2-C.sub.20 alkenyloxy,
C.sub.2-C.sub.20 alkynyloxy, aryloxy, C.sub.2-C.sub.20
alkoxycarbonyl, C.sub.1-C.sub.20 alkylthio, C.sub.1-C.sub.20
alkylsulfonyl and C.sub.1-C.sub.20 alkylsulfinyl.
[0013] In particularly preferred embodiments, the initiator is as
described above wherein R is hydrogen, R.sup.1 is phenyl or
(--CH.dbd.CPh.sub.2), X and X.sup.1 are both chloride, and L and
L.sup.1 ligands are --P(cyclohexyl).sub.3; the cycloalkene is
cyclooctadiene; and the chain transfer agent is
cis-2-butene-1,4-diol dimethacrylate or cis-2-butene-1,4-diol
diglycidyl ether.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is an illustrative reaction scheme for the synthesis
of a telechelic polymer with methacrylate end groups.
[0015] FIG. 2 is graphic representation of the dependence of the
observed M.sub.n values for the bis(methacrylate)-functionalized
telechelic poly(butadiene)s 9 on the [COD]/[CTA] ratio. The M.sub.n
was determined by .sup.1H NMR integration assuming a number average
functionality of 2.0.
[0016] FIG. 3 is a graphic representation of the dependence of the
observed M. values for the bis(epoxide)-functionalized telechelic
poly(butadiene)s 10 on the [COD]/[CTA] ratio. The M.sub.n was
determined. by .sup.1H NMR integration assuming a number average
functionality of 2.0.
DETAILED DESCRIPTION OF THE INVENTION
[0017] The present invention relates to novel organic polymers with
crosslinkable end groups and to a simplified and direct procedure
for the synthesis of these polymers. These crosslinkable end groups
may be subsequently reacted to form a network of crosslinked
polymers.
[0018] The present invention relates to unbranched or linear
telechelic polymers of the general formula ##STR7## wherein: [0019]
n is an integer; ##STR8## is a alkadienyl group; [0020] Y is an
alkyl group; and, [0021] Z is a crosslinkable end group.
[0022] As used herein, an alkadienyl group is a hydrocarbon having
at least two carbon-carbon double bonds. In preferred embodiments,
##STR9## is a C.sub.4-C.sub.20 alkadienyl group; Y is an
C.sub.1-C.sub.10 alkyl and Z is selected from the group consisting
of Z is selected from a group consisting of methacrylate, acylate,
cinnamate, epoxide, lactone, cyclic carbonate, tetrahydrofuran,
oxetane, lactams, phosphazenes, and alkoxysilanes. In more
preferred embodiments, Y is a C.sub.1-C.sub.3 alkyl and Z is
methacrylate or epoxide.
[0023] In another aspect of the present invention, telechelic
polymers of the formula ##STR10## are disclosed wherein: [0024] n
is an integer; ##STR11## is an alkadienyl group; and, [0025] Z is a
crosslinkable end group.
[0026] In preferred embodiments, ##STR12## is a C.sub.4-C.sub.20
alkadienyl group and Z is selected from the group consisting of
methacrylate, acylate, cinnamate, epoxide, lactone, cyclic
carbonate, tetrahydrofuran, oxetane, lactams, phosphazenes, and
alkoxysilanes. In more preferred embodiments, Z is methacrylate or
epoxide.
[0027] In yet another aspect of the present invention, telechelic
polymers of the formula ##STR13## wherein n is an integer and Z is
a crosslinkable end group. In preferred embodiments, Z is selected
from the group consisting of methacrylate, acylate, cinnamate,
epoxide, lactone, cyclic carbonate, tetrahydrofuran, oxetane,
lactams, phosphazenes, and alkoxysilanes. In more preferred
embodiments, Z is methacrylate or epoxide.
[0028] In another embodiment of the present inventions, methods for
synthesizing the above disclosed telechelic polymers are
provided.
Initiators
[0029] In general, initiators (or catalysts) that may be used in
the practice of the present invention are ruthenium or osmium
carbene complexes that include a ruthenium or osmium metal center
that is in a +2 oxidation state, have an electron count of 16, and
are penta-coordinated. More specifically, the initiators are of the
formula ##STR14## wherein: [0030] M is ruthenium or osmium; [0031]
X and X.sup.1 are independently any anionic ligand; [0032] L and
L.sup.1 are any neutral electron donor ligand; [0033] R and R.sup.1
are each hydrogen or one of the following substituent groups:
C.sub.1-C.sub.20 alkyl, C.sub.2-C.sub.20 alkenyl, C.sub.2-C.sub.20
alkynyl, aryl, C.sub.1-C.sub.20 carboxylate, C.sub.1-C.sub.20
alkoxy, C.sub.2-C.sub.20 alkenyloxy, C.sub.2-C.sub.20 alkynyloxy,
aryloxy, C.sub.2-C.sub.20 alkoxycarbonyl, C.sub.1-C.sub.20
alkylthio, C.sub.1-C.sub.20 alkylsulfonyl and C.sub.1-C.sub.20
alkylsulfinyl. Optionally, the substituent group may be substituted
with one or more groups selected from C.sub.1-C.sub.5 alkyl,
C.sub.1-C.sub.5 alkoxy, and aryl. When the substitute aryl group is
phenyl, it may be further substituted with one or more groups
selected from a halogen, a C.sub.1-C.sub.5 alkyl, or a
C.sub.1-C.sub.5 alkoxy. Moreover, the initiator may further include
one or more functional groups. Examples of suitable functional
groups include but are not limited to: hydroxyl, thiol, thioether,
ketone, aldehyde, ester, ether, amine, imine, amide, nitro,
carboxylic acid, disulfide, carbonate, isocyanate, carbodiimide,
carboalkoxy, carbamate, and halogen.
[0034] These ruthenium and osmium carbene complexes have been
described in U.S. Pat. Nos. 5,312,940, 5,342,909, 5,710,298, and
5,831,108 and PCT Publication No. WO 98/21214, all of which are
incorporated herein by reference.
[0035] In preferred embodiments of these catalysts, the R
substituent is hydrogen and the R.sup.1 substituent is selected
from the group consisting C.sub.1-C.sub.20 alkyl, C.sub.2-C.sub.20
alkenyl, and aryl. In even more preferred embodiments, the R.sup.1
substituent is phenyl or vinyl, optionally substituted with one or
more moieties selected from the group consisting of C.sub.1-C.sub.5
alkyl, C.sub.1-C.sub.5 alkoxy, phenyl, and a functional group. In
especially preferred embodiments, R.sup.1 is phenyl or vinyl
substituted with one or more moieties selected from the group
consisting of chloride, bromide, iodide, fluoride, --NO.sub.2,
--NMe.sub.2, methyl, methoxy and phenyl. In the most preferred
embodiments, the R.sup.1 substituent is phenyl.
[0036] In preferred embodiments of these catalysts, L and L.sup.1
are each independently selected from the group consisting of
phosphine, sulfonated phosphine, phosphate, phosphinite,
phosphonite, arsine, stibine, ether, amine, amide, imine,
sulfoxide, carboxyl, nitrosyl, pyridine, and thioether. In more
preferred embodiments, L and L.sup.1 are each a phosphine of the
formula PR.sup.3R.sup.4R.sup.5, where R.sup.3, R.sup.4, and R.sup.5
are each independently aryl or C.sub.1-C.sub.10 alkyl, particularly
primary alkyl, secondary alkyl or cycloalkyl. In the most preferred
embodiments, the L and L.sup.1 ligands are each selected from the
group consisting of --P(cyclohexyl).sub.3, --P(cyclopentyl).sub.3,
--P(isopropyl).sub.3, and --P(phenyl).sub.3.
[0037] In preferred embodiments of these catalysts, X and X.sup.1
are each independently hydrogen, halide, or one of the following
groups: C.sub.1-C.sub.20 alkyl, aryl, C.sub.1-C.sub.20 alkoxide,
aryloxide, C.sub.3-C.sub.20 alkyldiketonate, aryldiketonate,
C.sub.1-C.sub.20 carboxylate, arylsulfonate, C.sub.1-C.sub.20
alkylsulfonate, C.sub.1-C.sub.20 alkylthio, C.sub.1-C.sub.20
alkylsulfonyl, or C.sub.1-C.sub.20 alkylsulfinyl. Optionally, X and
X.sup.1 may be substituted with one or more moieties selected from
the group consisting of C.sub.1-C.sub.10 alkyl, C.sub.1-C.sub.10
alkoxy, and aryl which in turn may each be further substituted with
one or more groups selected from halogen, C.sub.1-C.sub.5 alkyl,
C.sub.1-C.sub.5 alkoxy, and phenyl. In more preferred embodiments,
X and X.sup.1 are halide, benzoate, C.sub.1-C.sub.5 carboxylate,
C.sub.1-C.sub.5 alkyl, phenoxy, C.sub.1-C.sub.5 alkoxy,
C.sub.1-C.sub.5 alkylthio, aryl, and C.sub.1-C.sub.5 alkyl
sulfonate. In even more preferred embodiments, X and X.sup.1 are
each halide, CF.sub.3CO.sub.2, CH.sub.3CO.sub.2 CFH.sub.2CO.sub.2,
(CH.sub.3).sub.3CO, (CF.sub.3).sub.2(CH.sub.3)CO,
(CF.sub.3)(CH.sub.3).sub.2CO, PhO, MCO, EtO, tosylate, mesylate, or
trifluoromethanesulfonate. In the most preferred embodiments, X and
X.sup.1 are each chloride.
[0038] The most preferred initiators in the practice of the present
invention are as described above wherein M is ruthenium; X and
X.sup.1 are both chloride; L and L.sup.1 ligands are both
--P(cyclohexyl).sub.3; R is hydrogen; and R.sup.1 is either phenyl
(3), (--CH.dbd.CPh.sub.2) (4), or (CH.dbd.C(CH.sub.3).sub.2).
[0039] The above initiators are stable in the presence of a variety
of functional groups including hydroxyl, thiol, ketone, aldehyde,
ester, ether, amine, imine, amide, nitro, carboxylic acid,
disulfide, carbonate, isocyanate, carbodiimide, carboalkoxy, and
halogen. Therefore, the starting materials and products of the
reactions described below may contain one or more of these
functional groups without poisoning the catalyst. In addition, the
initiators are stable in the presence of aqueous, organic, or
protic solvents, including aromatic hydrocarbons, chlorinated
hydrocarbons, ethers, aliphatic hydrocarbons, alcohols, water, or
mixtures of the above.
[0040] Using an initiator described above, practice of one
embodiment of the inventive method may be summarized as follows:
##STR15## wherein: [0041] n is an integer; ##STR16## is a
cycloalkene; [0042] Z--Y.dbd.Y--Z is a chain transfer agent wherein
Z is a crosslinkable end group and --Y.dbd.Y-- is an alkenyl group;
and, ##STR17## is the resulting telechelic polymer.
[0043] Any cycloalkene (also referred to as cyclic olefin) that can
participate in a ring-opening metathesis polymerization ("ROMP")
reaction may be used. Because of the generally high metathesis
activity of the initiators of the present invention, the
cycloalkene may be strained or unstrained. In addition, the
cycloalkene may include one or more substituent groups selected
from the group consisting of C.sub.1-C.sub.10 alkyl,
C.sub.2-C.sub.10 alkenyl, C.sub.2-C.sub.10 alkynyl, and aryl and
one or more functional groups selected from the group consisting of
hydroxyl, thiol, thioether, ketone, aidehyde, ester, ether, amine,
imine, amide, nitro, carboxylic acid, disulfide, carbonate,
isocyanate, carbodiimide, carboalkoxy, carbamate, and halogen.
[0044] Illustrative examples of suitable cycloalkenes include but
are not limited to: norbornene, norbornadiene, cyclopentene,
dicyclopentadiene, cyclo-octene, 7-oxanorbornene,
7-oxanorbornadiene, cyclodocene, 1,3-cyclooctadiene,
1,5-cyclooctadiene, 1,3-cycloheptadiene, and derivatives thereof.
In preferred embodiments, the cycloalkene is a cycloalkadiene. In
more preferred embodiments, the cycloalkene is selected from the
group consisting of norbornadiene, dicyclopentadiene,
1,3-cyclooctadiene, 1,5-cyclooctadiene, 1,3-cycloheptadiene, and
derivatives thereof. The use of 1,3-cyclooctadiene or
1,5-cyclooctadiene as the cycloalkene is most preferred.
[0045] The chain transfer agent ("CTA") is of the general formula,
Z--Y.dbd.Y--Z, wherein --Y.dbd.Y-- is an alkenyl group and Z is a
crosslinkable end group. As used herein, a crosslinkable end group
is group that is capable of forming a covalent bond either by
reacting directly with another crosslinkable end group or by
reacting indirectly through a crosslinking agent with another
crosslinkable end group.
[0046] In preferred embodiments, --Y.dbd.Y-- is a C.sub.2-C.sub.20
alkene and Z is selected from a group consisting of methacrylate,
acylate, cinnamate, epoxide, lactone, cyclic carbonate,
tetrahydrofuran, oxetane, lactams, phosphazenes, and alkoxysilanes.
In more preferred embodiments, --Y.dbd.Y-- is a C.sub.2-C.sub.20
alkenyl and Z is methacrylate or epoxide. In the most preferred
embodiments, the chain transfer agent is cis-2-butene-1,4-diol
dimethacrylate (5) or cis-2-butene-1,4-diol diglycidyl ether
(6).
[0047] In another embodiment, the inventive method may be
summarized as follows: ##STR18## wherein [0048] n is an integer
##STR19## is a cycloalkene; ##STR20## is a chain transfer agent
wherein Z is a crosslinkable end group; and, ##STR21## is the
resulting telechelic polymer.
[0049] In preferred embodiments, the cycloalkene is selected from a
group consisting of norbornene, norbornadiene, cyclopentene,
dicyclopentadiene, cyclo-octene, 7-oxanorbornene,
7-oxanorbornadiene, cyclodocene, 1,3-cyclooctadiene,
1,5-cyclooctadiene, 1,3-cycloheptadiene, and derivatives thereof,
and Z is selected from the group consisting of methacrylate,
acylate, cinnamate, epoxides, lactone, cyclic carbonate,
tetrahydrofuran, oxetane, lactams, phosphazenes, and
alkoxysilanes.
[0050] In more preferred embodiments, the cycloalkene is a
cycloalkadiene. In especially preferred embodiments, the
cycloalkene is selected from the group consisting of norbornadiene,
dicyclopentadiene, 1,3-cyclooctadiene, 1,5-cyclooctadiene,
1,3-cycloheptadiene, and derivatives thereof, and Z is methacrylate
or epoxide. The use of 1,3-cyclooctadiene or 1,5-cyclooctadiene as
the cycloalkene, and cis-2-butene-1,4-diol dimethacrylate (5) or
cis-2-butene-1,4-diol diglycidyl ether (6) as the chain transfer
agent is most preferred.
[0051] In another embodiment, the inventive method may be described
as follows: ##STR22## is an integer and Z is a crosslinkable
end.
[0052] In preferred embodiments, Z is selected from the group
consisting of methacrylate, acylate, cinnamate, epoxides, lactone,
cyclic carbonate, tetrahydrofuran, oxetane, lactams, phosphazenes,
and alkoxysilanes. In the most preferred embodiments, Z is either
##STR23##
[0053] In addition to the ease of synthesis, the molecular weight
of the telechelic polymer product may be readily controlled by
modulating the ratio of the cycloalkene concentration to the chain
transfer agent concentration. In a surprising and unexpected
finding, the molecular weight of the resulting polymer is directly
proportional to the molecular weight of the resulting telechelic
polymer. As a result, by modulating the starting materials in the
form of a [cycloalkene]/[chain transfer agent] ratio, the
telechelic polymers having the desired molecular weight may be
synthesized.
[0054] For the purposes of clarity, the specific details of the
present invention will be illustrated with reference to especially
preferred embodiments wherein the initiator is 3 or 4, the
cycloalkene is cyclooctadiene, and the chain transfer agent is
cis-2-butene-1,4-diol dimethacrylate (5) or cis-2-butene-1,4-diol
diglycidyl ether (6). However, it should be appreciated that these
embodiments and the appended experimental protocols are for
purposes of illustration only and are not intended to limit the
scope of the present invention.
Synthesis of the cis-2-butene-1,4-diol dimethacrylate.
[0055] Synthesis of the bis(methacrylate)-functionalized chain
transfer agent, cis-2-butene-1,4-diol dimethacrylate (5), was
accomplished as shown in Scheme 1. ##STR24##
[0056] Commercially available cis-2-butene-1,4-diol was esterified
using methacryloyl chloride to synthesize compound 5 in 72% yield.
Because compound 5 was not generally stable, it was stored at
-30.degree. C. with 20 weight percent of p-methoxyphenol (a free
radical inhibitor). In this manner, compound 5 was stored for over
six months without any appreciable degradation or polymerization.
Because of the general tolerance of initiators 3 and 4, compound 5
could be used without removing p-methoxyphenol prior to its use in
polymerization reactions.
Synthesis of the cis-2-butene-1,4-diol diglycidyl ether.
[0057] The synthesis of the bis(epoxide)-functionalized chain
transfer agent, cis-2-butene-1,4-diol diglycidyl ether (6), was
accomplished in one step as illustrated in Scheme 2. ##STR25##
[0058] cis-2-butene-1,4-diol was treated with excess
epichlorohydrin in the presence of aqueous NaOH (50% w/w) and the
phase transfer catalyst, Bu.sub.4N.sup.+HSO.sub.4.sup.- to resulted
in chain transfer agent 6 in 65% yield. Because compound 6 was
extremely stable, it was purified by distillation at
105-110.degree. C. in vacuo. Samples of compound 6 stored at room
temperature for over six months, exhibited virtually no
decomposition or polymerization.
Reaction of CTAs 5 and 6 with the Ruthenium Benzylidene Initiator
3.
[0059] As shown by FIG. 1, the generation of an end group
functionalized ruthenium alkylidene species is a key step in the
practice of the present invention. However, it was initially
unclear whether a ROMP-type protocol using a chain transfer agent,
Z--Y.dbd.Y--Z, would be a viable synthetic strategy. Previous
mechanistic studies indicated that ruthenium-based metathesis
initiators including 3 and 4 were susceptible to a side reaction
where the functional end group (e.g. from a chain transfer agent)
would chelate to the metal center with a concomitant loss of a L
ligand (typically a phosphine). The resulting chelated species were
less reactive and often decomposed on the time scale of a typical
polymerization reaction. Consequently, whether reactions of
ruthenium benzylidene 3 with both 5 and 6 would proceed according
to Scheme 4 were investigated. ##STR26##
[0060] Unexpectedly, treatment of 3 with 50 equivalents of the
bis(methacrylate)-functionalized CTA 5 at 45.degree. C. for 30 min
resulted in the formation of a methacrylate-functionalized
ruthenium alkylidene 7 as outlined by Scheme 4. Alkylidene 7
exhibited an cc-H carbene resonance at 19.48 ppm (t, J.sub.HH=4.4
Hz) in the .sup.1H NMR and a .sup.31P resonance at 37.42 ppm with
no observed free phosphine. Moreover, alkylidene 7 showed no
decomposition over 24 hours at room temperature.
[0061] Similarly, treatment of 3 with 50 equivalents of the
bis(epoxide)-functionalized CTA 6 at 45.degree. C. for 30 min
resulted in the formation of an epoxide-functionalized ruthenium
alkylidene 8. This alkylidene exhibited an .alpha.-H carbene
resonance at 19.79 ppm (t, J.sub.HH=3.6 Hz) in the .sup.1H NMR and
a .sup.31P resonance at 36.91 ppm with no observed free phosphine.
Decomposition of alkylidene 8 was not observed even after being
stored for 24 hours at room temperature. As a result, the lack of
observed free phosphine and the .sup.1H and .sup.31P resonances
indicated that telechelic polymers with crosslinkable end groups
may be synthesized using ROMP in the presence of a chain transfer
agent of the general formula Z--Y.dbd.Y--Z.
Polymerization of COD in the Presence of 5.
[0062] In the presence of the CTA 5, polymerization of COD resulted
in the bis(methacrylate)-functionalized telechelic poly(butadiene)
9 as shown in Scheme 5. ##STR27##
[0063] In an initial study, the impact of the [COD]/[3]
([COD]/[initiator]) ratio, reaction time, and temperature on the
polymer yield and CTA incorporation was investigated. The
polymerizations were run neat according to the different sets of
conditions described in Table 1.
[0064] In the first two entries, reaction time and temperature were
held constant at 24 h and 25.degree. C. while the [COD]/[initiator]
ratio was increased from 2000:1 to 4000:1. Although only a slight
decrease in the yield of 5% was observed, the M.sub.n increased
from 3500 to 5500 presumably due to a reduced incorporation of the
CTA 5 during the polymerization. The impact of reaction time was
investigated by comparing the results for reaction times of 24 and
48 hours (at: [COD]/[5]=10; [COD]/[initiator]=2000; and a
temperature of 25.degree. C.). As seen in the third and fourth
entries, increasing the reaction time resulted in a slight increase
in yield and a lower molecular weight due to an improved
incorporation of 5. Unfortunately, the impact of temperature was
unable to be investigated because of the relative instability of 5.
For example, presumably due to the thermally-induced polymerization
of the methacrylate groups, insoluble polymeric materials were
formed when polymerizations were run at 45.degree. C.
[0065] Based on these results, all COD polymerization reactions
with 5 were run with a [COD]/[initiator] ratio of 2000:1 for 48
hours at 25.degree. C. In addition, efforts were taken to minimize
photo-induced polymerization of the methacrylate groups by
shielding the reaction vesicle from light. TABLE-US-00001 TABLE 1
M.sub.n [COD]/ [COD]/ Rxn. Temp. % (Theo- M.sub.n [5] [initiator]
Time (h) (C. .degree.) Yield.sup.a retical).sup.b (NMR).sup.c 15
2000 24 25 80 1844 3500 15 4000 24 25 75 1844 5500 10 2000 24 25 85
1304 2500 10 2000 48 25 87 1304 2300 .sup.aIsolated yields after
purification. .sup.bDetermined by ([COD]/[5])(MW of COD) + (MW of
5). .sup.cDetermined by .sup.1H NMR integration assuming a number
average ftmctionality of 2.
[0066] Practice of the present invention is extremely advantageous
because of the ability to control the polymer molecular weights
through the manipulation of the [monomer]/[CTA] ratio. A series of
bis(methacrylate)-functionalized telechelic poly(butadiene)s were
synthesized with [COD]/[5] ratios of 15, 40, 60, and 80:1. As shown
by Table 2, yields between 88-90% were obtained, and the molecular
weight was indeed controlled resulting in
bis(methacrylate)-functionalized telechelic poly(butadiene)s with
M.sub.n values between 3700 to 17700. TABLE-US-00002 TABLE 2 % cis-
% cis- Olefin Olefin [COD]/ % (Back- (End M.sub.n M.sub.n [5]
Yield.sup.d bone).sup.e Group).sup.e (NMR).sup.f (GPC).sup.g
PDI.sup.h 15.sup.a 88 50 25 3700 5400 1.74 40.sup.a 89 55 20 8000
10100 1.86 60.sup.b 90 60 25 14500 11900 2.02 80.sup.c 90 55 25
17700 15300 1.99 .sup.aPolymerizations were run neat at 25.degree.
C. for 48 h with [COD]/[iinitiatorl = 2000. .sup.bTo ensure better
mixing and higher yields, [COD] = 12.4 M in benzene was utilized.
.sup.cTo ensure better mixing and higher yields, [COD] = 9.3 M in
benzene was utilized. .sup.dIsolated yields after purification.
.sup.eDetermined by .sup.1H NMR integration. .sup.fDetermined by
.sup.1H NNIR integration assuming a number average functionality of
2. .sup.gDeterniined by gel permeation chromatography in
CH.sub.2Cl.sub.2 relative to monodispersed polystyrene
standards.
[0067] As illustrated in the plot of M.sub.n versus the [COD]/[5]
ratio in FIG. 1, a direct correlation was observed between the
[COD]/[5] ratio and polymer molecular weight. Although the
experimentally observed molecular weights were higher than that
calculated for the theoretical molecular weights, this is believed
to be due to the incomplete incorporation of the chain transfer
agent 5 during the polymerization.
[0068] The resulting telechelic poly(butadiene)s contained between
50-60% cis-olefin in the backbone and between 20-25% cis-olefin at
the polymer end groups, and polydispersities (PDls) of 1.74-2.02
were obtained. Both .sup.1H and .sup.13C NMR indicated an F.sub.n
value near 2.
Polymerization of COD in the Presence of 6.
[0069] Polymerization of COD in the presence of the chain transfer
agent 6 resulted in bis(epoxide)-functionalized telechelic
poly(butadiene) 10 as shown in Scheme 6. ##STR28##
[0070] The impact of the [COD]/[CTA] ratio, reaction time, and
temperature on the polymer yield and the incorporation of 6 was
examined. All polymerization reactions were run neat according to
the conditions described in Table 3. TABLE-US-00003 TABLE 3 [COD]/
[COD]/ Rxn. Temp. % M.sub.n [6] [initiator] Time (h) (.degree. C.)
Yield.sup.a (NMR).sup.b 15 2000 48 25 60 3700 15 4000 48 25 51 3600
15 2000 24 45 67 3400 15 2000 48 45 67 3400 15 4000 24 45 63 3500
15 4000 48 45 61 3700 .sup.aIsolated yields after purification.
.sup.bDetermined by ([COD]/[6])(MW of COD) + (MW of 6).
.sup.bDetermined by .sup.1H NMR integration assuming a number
average functionality of 2.
[0071] Despite similar molecular weight values, a lower yield (51%
compared to 60%) was observed at the lower initiator loading. As a
result, polymerization reactions in the presence of 6 were run at
25.degree. C. and at a 2000:1 [COD]/[initiator] ratio. However,
unlike the polymerization of COD in the presence of 5,
polymerization reactions could be run at higher temperatures
because of the relative stability of 6. Comparing entries 3-6 in
Table, similar yields and molecular weights were observed
regardless of changes in the reaction time or the (COD]/[initiator)
ratio. Therefore, based on these results, all COD polymerization
reactions in the presence of chain transfer agent 6 were carried
out at 45.degree. C. with a [COD]/[initiator] ratio of 4000:1 for
24 hours.
[0072] The effect of the [COD]/[CTA] ratio was also investigated.
By varying the [COD]/[6] ratio from 15 to 80:1, M.sub.n values
between 3000-16800 were obtained with yields between 71-87% (see
Table 4). TABLE-US-00004 TABLE 4 % cis- % cis- Olefin Olefin [COD]/
% (Back- (End M.sub.n M.sub.n [6] Yield.sup.d bone).sup.e
Group).sup.e (NMR).sup.f (GPC).sup.g (PDI).sup.g 15.sup.a 71 60 30
3000 4000 1.55 40.sup.a 80 65 25 7800 6900 1.89 60.sup.b 87 50 30
11000 10500 1.87 80.sup.c 84 55 25 16800 11600 1.94
.sup.aPolymerizations were run neat at 45.degree. C. for 24 h with
[COD]/[initiator] = 4000. .sup.bTo ensure better mixing and higher
yields, [CODI = 12.4 M in benzene was utilized. .sup.cTo ensure
better mixing and higher yields, [COD] = 9.3 M in benzene was
utilized. .sup.dIsolated yields after purification.
.sup.eDetermined by .sup.1H NMR integration. .sup.fDetermined by
.sup.1H NMR integration assuming a number average functionality of
2. .sup.gDetermined by gel permeation chromatography in
CH.sub.2CL.sub.2 relative to monodispersed polystyrene
standards.
[0073] As shown by FIG. 3, an excellent correlation was observed
between the [COD]/[6] and polymer molecular weight (M.sub.n). The
bis(epoxide)-functionalized telechelic poly(butadiene)s 10
contained between 50-65% cis-olefins in the backbone and between
25-30% cis-olefins in the end groups. The observed PDls ranged from
1.55 to 1.94. Both .sup.1H and .sup.13C NMR indicated an F.sub.n
near 2 for these materials.
Crosslinking of the telechelic poly(butadiene)s 9 and 10.
[0074] Crosslinking studies of the telechelic poly(butadiene)s 9
and 10 were conducted. Bis(methacrylate)-functionalized telechelic
poly(butadiene)s 9 was crosslinked using both thermal and
photochemical methods. For thermal crosslinking, concentrated
solutions of polymer 9 (100 mg of polymer 9 in 200 .mu.L toluene)
(M.sub.n values between 3700 to 17700) were combined with benzoyl
peroxide (2 wt %) and heated to 90.degree. C. Within 5 minutes, a
tacky insoluble material was observed, and within 15 minutes, a
rubbery polymeric solid was formed which was completely insoluble
in all common organic solvents including CH.sub.2Cl.sub.2,
CHCl.sub.3, benzene, toluene, Et.sub.2O, ethyl acetate, and
DMSO.
[0075] Photochemical crosslinking was induced by combining either
benzoyl peroxide or 2,2-dimethoxy-2-phenylacetophenone (2 wt %)
with the concentrated polymer solutions and photolyzing the
solutions for 15 minutes using a 450 watt medium pressure mercury
Hanovia lamp. As in the thermally-induced cross-linking reactions,
a tacky insoluble material was formed within 5 minutes and a highly
crosslinked rubbery material was obtained after 15 minute.
[0076] Bis(epoxide)-functionalized telechelic poly(butadiene)s 10
was crosslinked using an acid. Solutions of polymer 10 (100 mg of
polymer 10 in 500 .mu.L toluene; M.sub.n values between 3000 to
16800) were stirred with a magnetic stirrer and treated with
H.sub.2SO.sub.4 (cat.). Upon addition of the acid, a rubbery
polymeric solid was immediately observed which was insoluble in all
common organic solvents including CH.sub.2Cl.sub.2, CHCl.sub.3,
benzene, toluene, Et.sub.2O, ethyl acetate, and DMSO. Treatment
with other acids such as HCl (1 M in Et.sub.2O) and
p-toluenesulfonic acid resulted in no significant cross-linking
even at elevated temperatures. Treatment of the polymer solutions
with BF.sub.3-Et.sub.2O (cat.) resulted in crosslinking, however
the crosslinking required between 2 and 3 hours at room temperature
and often gave inconsistent results. Treatment with H.sub.2SO.sub.4
(cat.) was by far the simplest and most rapid method for the
crosslinking of the bis(epoxide)-functionalized telechelic
poly(butadiene)s 10.
[0077] It is to be understood that while the invention has been
described in conjunction with the preferred specific embodiments
thereof, that the foregoing description as well as the examples
that follow are intended to illustrate and not limit the scope of
the invention. Other aspects, advantages and modifications within
the scope of the invention will be apparent to those skilled in the
art to which the invention pertains.
[0078] All patents, patent applications, and publications mentioned
herein are hereby incorporated by reference in their
entireties.
EXPERIMENTAL
General Protocols
[0079] Argon was purified by passage through columns of BASF R-11
catalyst (Chemalog) and 4 .ANG. molecular sieves (Linde). NMR
spectra were recorded on GE QE-300 Plus (300.1 MHz; 75.49 MHz
.sup.13C) spectrometer and a JEOL GX-400 (399.65 MHz .sup.1H; 100
MHz .sup.13C; 161.85 MHz .sup.31P) spectrometer. .sup.31P NMR
spectra were referenced to an external 85% H.sub.3PO.sub.4
standard. IR spectra were recorded on a Perkin-Elmer 1600 series
FT-IR spectrometer. Gel permeation chromatographs were obtained on
a HPLC system using an Altex model 110A pump, a Rheodyne model 7125
injector with a 100 .mu.L injection loop, two American Polymer
Standards 10 micron mixed bed columns, and a Knauer
differential-refractometer using CH.sub.2Cl.sub.2 as eluent at a
1.0 mL/min flow rate. Molecular weights and polydispersities were
reported versus monodispersed polystyrene standards. Photolysis was
accomplished with a 450 watt medium pressure mercury Hanovia
lamp.
Materials
[0080] The benzene used in polymerizations was distilled from
CaH.sub.2 under vacuum. Dry THF was obtained by distillation under
atmospheric pressure from CaH.sub.2. All other solvents were
reagent grade and used without purification. cis-2-butene-1,4-diol,
methacryloyl chloride, triethylamine, NaOH,
Bu.sub.4N.sup.+HSO.sub.4.sup.-, epichlorohydrin, p-methoxyphenol,
MEOH, benzoyl peroxide, 2,2-dimethoxy-2-phenylacetophenone,
BF.sub.3Et.sub.2O, and H.sub.2SO.sub.4 were purchased from the
Aldrich Chemical Company and used without further purification. COD
was purchased from the Aldrich Chemical Company and degassed by
stirring in vacuo for 2 hours before use in polymerizations.
Preparation of cis-2-butene-1,4-diol dimethacrylate (5).
[0081] cis-2-butene-1,4-diol (14.04 g, 0.16 mol, 1.0 eq) was mixed
with THF (500 mL) and triethylamine (40.34 g, 0.48 mol, 3.0 eq) in
a 1 L round bottom flask under argon. To the reaction flask 90%
methacryloyl chloride (53.9 g, 0.46 mol, 2.9 eq) was added via an
addition funnel over 1 h at 0.degree. C. during which time a white
precipitate was observed. The ice bath was then removed, and the
reaction was left to stir overnight at room temperature. Deionized
water (150 mL) was then added to dissolve the precipitated salts,
and the reaction mixture was poured into a 2 L separatory funnel
containing petroleum ether (750 mL). The organics were then washed
with deionized water (3.times.200 mL), aqueous NaOH (15% w/w,
4.times.200 ni-L), and deionized water (3.times.200 mL). The
organics were dried over MgSO.sub.4 and concentrated in vacuo. The
product was purified by flash column chromatography (silica gel, 5%
ethyl acetate/hexanes, R.sub.f=0.45) to give 26.5 g (74%) of pure
product as a viscous oil. To prevent crosslinking, this material
was stored with p-methoxyphenol (20 wt %) at -30.degree. C. in a
dry box. .sup.1H NMR (CDCl.sub.3) .delta. 6.08-6.06 (m, 2H),
5.81-5.71 (m, 2H), 5.54-5.52 (m, 2H), 4.78-4.69 (m, 4H), 1.90-1.89
(m, 6H); .sup.13C NMR (CDCl.sub.3) .delta. 166.95; 136.03, 128.01,
125.67, 60.26, 18.19; IR (thin film on a NaCl plate) 3105, 3036,
2981, 2959, 2929, 2894, 1719, 1637, 1512, 1452, 1403, 1378, 1348,
1318, 1293, 1152, 1012, 975, 942, 815, 734, 651 cm.sup.-1; HRM S
(CI) calcd for C.sub.12H.sub.16O.sub.4 (M+H).sup.+ 225.1127, found
225-1129.
Preparation of cis-2-butene-1,4diol diglycidyl ether (6).
[0082] In a 1L Erlenmeyer flask, epichlorohydrin (270 g, 3.00 mol,
10 eq), aqueous NaOH (50% w/w) (240 g, 3.00 mol, 10 eq), and
BU.sub.4N.sup.+HSO.sub.4.sup.- (5.0 g, cat.) were combined at room
temperature with magnetic stirring. A thermometer was placed in the
flask to monitor the temperature during the reaction. To this
flask, cis-2-butene-1,4-diol (26.5 g, 0.30 mol, 1 eq) was added
dropwise slowly over 30 min. The reaction was extremely exothermic,
and so the temperature was maintained between 30-40.degree. C. by
controlling the addition rate as well as by intermittent cooling in
an ice bath. At the end of the addition, the reaction temperature
remained near 40.degree. C. for approximately 1 h, and when it
began to cool, the reaction flask was heated at 40.degree. C. in an
oil bath for an additional 1 h. The flask was allowed to cool, and
then deionized water was added (200 mL). This mixture was then
extracted with Et.0 (3.times.200 mL), dried over MgSO.sub.4, and
concentrated in vacuo to obtain a yellow oil. This was distilled at
0.2 mm Hg/105-110.degree. C. to give a clear oil (38.0 g, 65%
yield). .sup.1H NMR (CDCl.sub.3) .delta. 5-8-5.61 (m, 2H),
4.11-4.00 (m, 4H), 3.67 (dd, J.sub.1=3.0 Hz, J.sub.2=11.4 Hz, 2H),
3.30 (dd, J.sub.1=5.7 Hz, J.sub.2=11.4 Hz, 2H), 3.11-3.06 (m, 2H),
2.73 (dd, J.sub.1=4.2 Hz, J.sub.2=4.8 Hz, 2H), 2.54 (dd,
J.sub.1=2.7 Hz, J.sub.2=4.8 Hz, 2H); .sup.13C NMR (CDCl.sub.3)
.delta. 129.13, 70.76, 66.74, 50.61, 44.03; IR (thin film on a NaCl
plate) 3055, 2999, 2922, 2867, 1511, 1472, 1439, 1411, 1327, 1253,
1162, 1094, 1016, 968, 947, 901, 855, 762 cm.sup.-1; HRMS (CI)
calcd for C.sub.12H.sub.180.sub.2 (M+H).sup.+ 201.1127, found
201.1128.
Reaction of CTAs 5 and 6 with the Ruthenium Bewlidene (3).
[0083] All manipulations were carried out in a dry box. In a 10 mL
vial, ruthenium benzylidene 3 (6.0 mg, 7.3e-6 mot, 1.0 eq), CTA
(either 5 or 6) (3.7e-4 mot, 50 eq), and C.sub.6D.sub.6 (0.70 mL)
were combined to form a homogeneous solution. This solution was
transferred to a NMR tube which was capped with a rubber septa and
removed from the dry box. The NMR tube was placed in an oil bath at
45.degree. C. for 30 min. After this time, the NMR tube was removed
from the oil bath, and the reaction was analyzed by both .sup.1H
and .sup.31P NMR.
General Polymerization Procedure.
[0084] All manipulations were carried out in a dry box. In a 10 mL
vial, the correct amount of either 5 or 6 and COD were weighed out.
In a separate vial, the initiator was weighed out and a stirbar
added, and this was combined with the COD/CTA mixture. The vial was
then capped, removed from the dry box, and left to stir for the
desired time. For reactions involving the methacrylate CTA 5,
aluminum foil was wrapped around the reaction vial to prevent
photo-induced crosslinking. At the end of the desired reaction
time, ethyl vinyl ether (600 eq relative to initiator) was pipetted
into the vial along with an equal volume of toluene. This was left
to stir for 1 h followed by precipitation into MeOH to isolate the
polymer. The MeOH was decanted away, and the polymer was washed
with excess fresh MeOH to remove any remaining COD or CTA. The
resulting telechelic poly(butadiene)s were concentrated in vacuo
and then characterized by standard methods including .sup.1H NMR,
.sup.13C NMR, IR, and GPC.
Bis(methacrylate)-functionalized telechelic poly(butadiene)
(9).
[0085] Spectral data for the polymer derived from a 15:1 [COD]/[5]
ratio (M.sub.n(NMR)=3700, DP=32). .sup.1H NMR (CDCl.sub.3) .delta.
6.13 (bs), 5.86-5.54 (bm), 4.68 (bd, J=6.0 Hz), 4.57 (bd, J=6.6
Hz), 2.43-1.72 (bm); .sup.13C NMR (CDCl.sub.3) .delta. 167.224,
167.14, 136.37, 135.49, 135.41, 134.50, 130.66, 130.42, 130.06,
129.94, 129.55, 129.38, 128.95, 128.76, 128.67, 125.34, 124.23,
124.14, 123.84, 123.67, 65.29, 60.60, 60.53, 32.93, 32.65, 32.28,
31.89, 27.66, 27.36, 27.01, 26.67, 18.34; IR (thin film on a NaCl
plate) 3005, 2937, 2844, 1721, 1655, 1639, 1446, 1403, 1318, 1294,
1239, 1159, 1079, 1010, 966, 814, 733 cm.sup.-1.
Bis(epoxide)-functionalized telechelic poly(butadiene) (10).
[0086] Spectral data for the polymer derived from a 15:1 [COD]/[6]
ratio (M.sub.n(NMR)=3000, DP=26). .sup.1H NMR (CDCl.sub.3) .delta.
5.77-5.17 (bm), 4.09-3.91 (bm), 3.72-3.61 (bm), 3.41-3.30 (bm),
3.17-3.08 (bm), 2.81-2.72 (bm), 2.62-2.53 (bm), 2.35-1.64 (bm);
.sup.13C NMR (CDCl.sub.3) .delta. 134.49, 134.43, 133.19, 130.26,
130.03, 129.93, 129.73, 129.52, 129.35, 126.19, 126.06, 125.90.
71.95, 70.65, 70.46, 66.81, 50.72, 44.33, 44.26, 32.91, 32.63,
32.29, 32.04, 27.97, 27.63, 27.35, 27.10, 26.76; IR (thin film on a
NaCl plate) 3006, 2918, 2846, 1654, 1437, 1403, 1348, 1312, 1240,
1158, 1101, 966, 845, 732 cm.sup.-1.
Cross-linking of bis(methacrylate)-functionalized telechelic
poly(butadiene)s (9).
[0087] In a 2 mL glass vial, polymer 9 (100 mg) was dissolved in
toluene (200 .mu.L) with either benzoyl peroxide or
2,2-dimethoxy-2-phenylacetophenone (2 mg, 2 wt %). This solution
was then either subjected to heat in an oil bath at 90.degree. C.
(benzoyl peroxide-initiated) or light using a 450 watt medium
pressure mercury Hanovia lamp (benzoyl peroxide- or
2,2-dimethoxy-2-phenylacetophenone-initiated) in a photolysis
chamber. Although an insoluble material was formed within 5 min
under these conditions for each of the different molecular weight
polymers synthesized, heating or photolysis for 15 min resulted in
a more highly crosslinked rubbery material which was completely
insoluble in all common organic solvents including
CH.sub.2Cl.sub.2, CHCl.sub.3, benzene, toluene, Et.sub.2O, ethyl
acetate, and DMSO.
Cross-linking of bis(epoxide)-functionalized telechelic
poly(butadiene)s (10).
[0088] In a 2 mL vial, polymer 10 (100 mg) was dissolved in toluene
(500 .mu.L) and a stir bar was added. This solution was then
stirred at room temperature and H.sub.2SO.sub.4 (cat.) was added.
Immediate formation of an insoluble rubbery solid was observed for
each of the different molecular weight polymers synthesized. These
materials were completely insoluble in all common organic solvents
including CH.sub.2Cl.sub.2, CHCl.sub.3, benzene, toluene,
Et.sub.2O, ethyl acetate, and DMSO.
* * * * *