Telechelic alkadiene polymers with crosslinkable end groups and methods for making the same
The present invention relates to telechelic polymers having crosslinkable end groups of the formula and methods for preparing the same wherein n is an integer; 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 wherein: M is ruthenium or osmium; X and X 1 are independently any anionic ligand; L and L 1 are any neutral electron donor ligand; R and R 1 are each hydrogen or a substituted or unsubstituted substituent wherein the substituent is selected from the group consisting of C 1 -C 20 alkyl, C 2 -C 20 alkenyl, C 1 -C 20 alkynyl, aryl, C 1 -C 20 carboxylate, C 1 -C 20 alkoxy, C 2 -C 20 alkenyloxy, C 2 -C 20 alkynyloxy, aryloxy, C 2 -C 20 alkoxycarbonyl, C 1 -C 20 alkylthio, C 1 -C 20 alkylsulfonyl and C 1 -C 20 alkylsulfinyl. In another aspect of the invention, methods for controlling the molecular weight of the resulting telechelic polymer are also presented.
1. A method for synthesizing a polymer of the formula
comprising contacting a cycloalkene with a initiator of the formula
in the presence of a chain transfer agent of the formula Z—Y═Y—Z wherein:
n is an integer;
—Y═Y— is an alkenyl group;
Z is a crosslinkable group;
M is ruthenium or osmium;
X and X 1 are independently any anionic ligand;
L and L 1 are any neutral electron donor ligand; and
R and R 1 are each hydrogen or a substituent group selected from the group consisting of C 1 -C 20 alkyl, C 2 -C 20 alkenyl, C 2 -C 20 alkynyl, aryl, C 1 -C 20 carboxylate, C 1 -C 20 alkoxy, C 2 -C 20 alkenyloxy, C 2 -C 20 alkynyloxy, aryloxy, C 2 -C 20 alkoxycarbonyl, C 1 -C 20 alkylthio, C 1 -C 20 alkylsulfonyl and C 1 -C 20 alkylsulfinyl, the substituent group optionally substituted with one or more moieties selected from the group consisting of C 1 -C 5 alkyl, C 1 -C 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 wherein:
—Y═Y— is a C 2 -C 20 alkene and Z is selected from a group consisting of methacrylate, acylate, cinnamate, epoxide, lactone, cyclic carbonate, tetrahydrofuran, oxetane, lactam, phosphazene, and alkoxysilane.
2. A method for synthesizing a polymer of the formula
comprising contacting a cycloalkene with a initiator of the formula
in the presence of a chain transfer agent of the formula
wherein:
n is an integer;
—Y═Y— is an alkenyl group;
Z is a crosslinkable group;
M is ruthenium;
X and X 1 are each halide;
L and L 1 each a phosphine of the formula PR 3 R 4 R 5 , where R 3 , R 4 , and R 5 are each independently aryl or C 1 -C 10 alkyl;
R is hydrogen; and,
R 1 is phenyl or vinyl, optionally substituted with one or more moieties selected from the group consisting of C 1 -C 5 alkyl, C 1 -C 5 alkoxy, phenyl, and a functional group selected from the group consisting of chloride, bromide, iodide, fluoride, —NO 2 , —NMe 2 , methyl, methoxy and phenyl wherein:
Z is selected from the group consisting of methacrylate, acylate, cinnamate, epoxide, lactone, cyclic carbonate, tetrahydrofuran, oxetane, lactam, phosphazene, and alkoxysilane.
3. A method for synthesizing a polymer of the formula
comprising reacting
with an initiator of the formula
in the presence of a chain transfer agent of the formula
wherein:
n is an integer;
Z is a crosslinkable group;
M is ruthenium;
X and X 1 are each chloride;
L and L 1 are each selected from the group consisting of —P(cyclohexyl) 3 , —P(cyclopentyl) 3 , —P(isopropyl) 3 , and —P(phenyl) 3 ;
R is hydrogen; and,
R 1 is phenyl or vinyl, optionally substituted with one or more moieties selected from the group consisting of C 1 -C 5 alkyl, C 1 -C 5 alkoxy, phenyl, and a functional group selected from the group consisting of chloride, bromide, iodide, fluoride, —NO 2 , —NMe 2 , methyl, methoxy and phenyl wherein:
Z is selected from a group consisting of methacrylate, acylate, cinnamate, epoxide, lactone, cyclic carbonate, tetrahydrofuran, oxetane, lactam, phosphazene, and alkoxysilane.
4. A method for preparing crosslinked polymers comprising:
contacting a cycloalkene with a initiator of the formula
in the presence of a chain transfer agent of the formula
to make a polymer of the formula
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′ is phenyl, (CH═CPh 2 ), or (CH═C(CH 3 ) 2 ).
5. The method as in claim 4 wherein Z is
and the crosslinking agent is heat in combination with benzoyl peroxide.
6. The method as in claim 4 wherein Z is
and the crosslinking agent is light in combination with benzoyl peroxide or 2,2-dimethoxy-2-phenylacetophenone.
7. The method as in claim 4 wherein Z is
and the crosslinking agent is H 2 SO 4 .