SYNTHESIS OF ALPHA-OMEGA-BIFUNCTIONAL FLUORINE-CONTAINING POLYSILOXANES BY HYDROSILATION REACTION

alpha,omega-Bis(trifluoroacetamide)-terminated polysiloxanes containin g Si-H bonds were prepared by cationic equilibration reaction of the c yclic tetramers, octamethylcyclotetrasiloxane and 1,3,5,7-tetramethylc yclotetrasiloxane, and bis( 3-aminopropyl)tetramethyldisiloxane, catal yzed by trifluoroacetic acid. The pendant Si-H silane bonds were then added quantitatively to 3,3,4,4,5,5,5-heptafluoro-1-pentene by using c hloroplatinic acid catalysis. The end groups of these fluorine-contain ing polysiloxanes were then hydrolyzed to unprotected primary amino gr oups. Carboxyl- or hydroxyl-terminated polysiloxanes were also prepare d by similar methods. Fluorine-containing siloxane-urea segmented copo lymers were synthesized by using alpha,omega-diamino-terminated polysi loxanes.