Networks containing perfluorocarbon organosilicon hyperbranched polymers
The present invention relates to hyperbranched copolymer networks containing hyperbranched copolymers that have perfluorocarbon and organosilicon entities that have high hydrophobicity, or high oleophobicity, or high thermal stability, or good adhesion to substrates, or any combinations thereof. This invention provides a further desirable combination of properties that include solubility before crosslinking, chemical resistance, and easy processibility. The copolymers may be crosslinked with a variety of crosslinking agents to give either rigid or elastomeric networks.
1. Hyperbranched copolymer networks which comprise hyperbranched copolymers containing perfluorocarbon and organosilicon entities that have
high hydrophobicity as shown by the water contact angle of the network surface in the range of about 95° to about 135°, and/or
high oleophobicity as shown by the CH 2 I 2 contact angle of the network surface of >90°, and/or
high thermal stability as shown by lack of degradation below 250° C., and/or
a glass transition temperature is in the range from about −120° C. to about 25° C., and/or
good adhesion to substrates, and/or
any combinations thereof, and
the networks should exhibit chemical resistance.
2. The hyperbranched copolymers of claim 1 wherein the hyperbranched copolymer is soluble before crosslinking and is readily processed.
3. The hyperbranched copolymers of claim 1 which are devoid of polar groups.
4. The hyperbranched copolymers of claim 1 containing reactive functional end-groups wherein they are crosslinkable by light, heat, moisture, radiation, catalysis, or chemical reaction with an appropriate crosslinking reagent.
5. A process for preparing hyperbranched copolymer networks as claimed in claim 1 , which comprises crosslinking hyperbranched copolymers having perfluorocarbon and organosilicon entities with a variety of crosslinking agents to form either rigid or elastomeric networks.
6. The process of claim 5 wherein the crosslinking agent is a linear telechelic diallyl(perfluorinated alkane-dimethylsiloxane) copolymer of the following formula:
CH 2 ═CHCH 2 [(CF 2 ) n′ C 3 H 6 (SiMe 2 O) n″ SiMe 2 C 3 H 6 ] n (CF 2 ) n′ CH 2 CH═CH 2
wherein:
n=degree of polymerization of the copolymer;
n′=4, 6 or 8; and
n″≧1.
7. The process of claim 5 wherein the crosslinking agent is a linear (perfluorinated alkane-dimethylsiloxane) copolymer of the following formula:
H(SiMe 2 O) n″ SiMe 2 [C 3 H 6 (CF 2 ) n′ C 3 H 6 (SiMe 2 O) n″ SiMe 2 ] n H
wherein:
n=degree of polymerization of the copolymer;
n′=4, 6 or 8; and
n″≧1.
8. A process for preparing hyperbranched copolymers of claim 1 which comprises reacting an organosilicon monomer containing —SiR 1 R 2 H groups, where R 1 and R 2 are independently alkyl, alkoxyl or H, and a perfluoroalkane containing allyl or vinyl functionalities, wherein the number of SiH or allyl (vinyl) functionalities must be equal to or greater than 2 and one must be equal to or greater than 3.
9. A process for preparing hyperbranched copolymers of claim 1 which comprises reacting organosilicon monomers containing vinyl or allyl functionalities, and perfluoroalkane monomers containing —SiR 1 R 2 H groups, where R 1 and R 2 are alkyl, alkoxyl or H, wherein the number of SiH or allyl (vinyl) functionalities must be equal to or greater than 2 and one must be equal to or greater than 3.
10. A process for preparing hyperbranched copolymers of claim 1 whenever prepared from organosilicon monomers containing —SiR 1 R 2 H groups, where R 1 and R 2 are alkyl, alkoxyl or H, and perfluoroalkane monomers containing vinylether (CH 2 ═CHO—) or allylether (CH 2 ═CHCH 2 O—) groups, wherein the number of SiH or allyl (vinyl)ether functionalities must be equal to or greater than 2 and one must be equal to or greater than 3.