POLYMERS BASED ON BLOCK CO-POLYMERS, PROCESS OF THEIR PREPARATION AND THEIR USE FOR PREPARING SHAPED PARTICLES

摘要

PCT No. PCT/CH95/00309 Sec. 371 Date Sep. 12, 1997 Sec. 102(e) Date Sep. 12, 1997 PCT Filed Dec. 27, 1995 PCT Pub. No. WO96/21167 PCT Pub. Date Jul. 11, 1996The invention relates to crosslinked polymers, which are polymerisation products of a polymerisable mixture that comprises the following components: a) a macromer of formula C wherein Macro is an m-valent radical of a macromer from which the number m of groups Rxx-H has been removed, each Rx, independently of the others, is a bond, -O-, -NRN- or -S- wherein RN is hydrogen or lower alkyl, PI* is a bivalent radical of a photoinitiator, Raa is the moiety of a photoinitiator that forms the less reactive free radical on cleavage of the photoinitiator, and m is an integer from 1 to 100, b) a copolymerisable vinyl monomer and c) a copolymerisable crosslinker. The polymers are suitable especially for the production of mouldings, such as for contact lenses.