摘要:
Curable silylated copolymers based on olefin copolymers comprising at least one alpha-olefin and a vinyl aromatic monomer (alkyl styrene) are prepared by reacting the olefin copolymer with an olefinically unsaturated hydrolyzable silane in the presence of a free radical generating agent. The silylated copolymers are readily curable by contact with water (moisture) and a silanol condensation catalyst and are particularly useful as the polymeric component in sealant, caulking, adhesive and coating formulations.
摘要:
A copolymer of isobutylene with 0.5 to 15 mole percent of a conjugated diene (i.e., a butyl rubber) is reacted with a silane having both an alkenyl group as well as at least two silicon-bonded hydrolyzable group, the reaction taking place in the presence of a free-radical generator, to provide a modified copolymer having reactive silyl groups grafted thereto. The modified copolymer exhibits a reduced molecular weight relative to the starting copolymer and may be used to formulate moisture-curable sealants, caulks, adhesive and coatings.
摘要:
The invention generally relates to thermoplastic blends having improved properties. Optionally, these blends may be dynamically vulcanized. More specifically, this invention is directed to a composition comprising a blend of chloromethylated(styrene-isobutylene)copolymer and a thermoplastic resin selected from the group consisting of polyamides, polyesters, polycarbonates, polysulfones, polyacetals, polyacetones, acrylonitrile-butadiene styrene resins, polyphenylene oxide, polyphenylene sulfide, styrene-acrylonitrile resins, styrene-maleic anhydride resins, polyamides, aromatic polyketones, ethylene vinyl alcohol copolymer and mixtures thereof. Tires and tire components such as air permeation prevention films comprising these compositions are also provided.
摘要:
Polyisobutylene (PIB) functionalized with terminal reactive unsaturation is disclosed. Carbocationically polymerized monohalogen-terminated PIB is dehydrohalogenated in a hydrocarbon solvent using an alkoxide of the formula RO-M wherein R is alkyl of at least 5 carbon atoms and M is alkali metal. The PIB obtained has terminal unsaturation which is 100% in the reactive ‘exo’ form which can be converted to succinic anhydride groups (PIB-SA) by the ene reaction with maleic anhydride. The PIB-SA is reactive with amine functional dendrimers to obtain a star-branched polymer having a dendrimer core and PIB branches joined by succininide linkages. Blends of the star-branched polymer with polypropylene have improved energy absorption properties and controllable moisture/oxygen permeabilities useful in films.
摘要:
Curable silylated copolymers based on olefin copolymers comprising at least one C4 to C7 isomonoolefin and a vinyl aromatic monomer (alkyl styrene) are prepared by reacting the olefin copolymer with an olefinically unsaturated hydrolyzable silane in the presence of a free radical generating agent. The silylated copolymers are readily curable by contact with water (moisture) and a silanol condensation catalyst and are particularly useful as the polymeric component in sealant, caulking, adhesive and coating formulations.
摘要:
There is provided a method of introducing ethylenically unsaturated functionality, into an alkylstyrene homopolymer or copolymer with an isoolefin, at the alkylbenzyl carbon atom comprising the steps of: forming a solution of the polymer in a hydrocarbon solvent; adding to the polymer solution an alkali metal (Na, K, Rb, Cs) alkoxide and an alkyl lithium compound to form a solution of a metalated intermediate; and adding a halodialkylalkenyl silane to the metalated polymer solution. Also provided are the ethylenically unsaturated functionalized polymer derivatives made by the method, and the crosslinked derivatives thereof.
摘要:
There is provided a method of introducing functionality into a copolymer of an isoolefin and an alkylstyrene at the alkylbenzyl carbon atom comprising the steps of: forming a solution of said copolymer in a hydrocarbon solvent; adding to said polymer solution an alkali metal Cs, K, Na alkoxide and an alkyl lithium compound to form a superbase with the polymer solution; and adding an electrophile to said base polymer solution also provided are the metalated copolymers and the functionalized derivative therefrom.
摘要:
Intervulcanized compositions having improved curing efficiency are prepared by the free radical curing of a mixture of an ethylenically unsaturated diolefin polymer such as natural or synthetic rubber and a saturated or low unsaturation polymer such as an ethylene propylene elastomers copolymer which contains functional groups pendant to the polymer chain. These functional groups contain an olefinic or vinyl double bond positioned alpha, beta to a substituent group which activates the double bond towards free radical addition reactions with the diolefin polymer. Preferred functionality includes benzylic ester functionality represented by the structure: ##STR1## wherein R.sub.2 and R.sub.3 are independently selected from hydrogen or C.sub.1 to C.sub.6 alkyl, and R.sub.4 is selected from hydrogen, C.sub.1 to C.sub.28 alkyl, aryl or C.sub.2 to C.sub.28 alkenyl.
摘要:
A copolymer having a substantially homogeneous composition distribution, said copolymer comprising the direct reaction product of an isoolefin and para-alkylstrene.