abstract |
Novel aniline terminated silicone monomers with (a) silane (Si--H) functionalities, (b) silanol (Si--OH) functionalities, or (c) alpha,omega-aniline terminated polydimethyl siloxanes, and a novel synthetic route. The alpha,omega-aniline terminated dimethyl siloxanes are prepared, starting with bromoaniline, in which the amine functionality is protected, such as by reaction with 1,1,4,4-tetramethyl-1,4-bis(N,N-diethylamino)-1,4-disilabutane, to form 1-(bromophenyl)-2,2,5,5-tetramethyl-l-aza-2,5-disilacyclopentane. The protected bromoaniline is then reacted with n-butyllithium and chlorodialkylsilane to form 1-((dialkylsilyl)phenyl)-2,2,5,5-tetramethyl-l-aza-2,5-disilacyclopentane. Next, the protected dimethylsilane aniline is subjected to de-protection to form aminophenyldialkyl silane, which is considered to be novel. This silane is then hydrolyzed to form the corresponding silanol, also considered to be novel. The silanol is then condensed to form bis(amino-phenyl)-1,1,3,3-tetraalkyldisiloxane. The amino group is in either the meta or para position, depending on the position of the bromo functionality in bromoaniline. The disiloxanes may be reacted further to form oligomers and polymers and may also be used to form copolymers. |