Polymers based on block copolymers

An ophthalmic molding, which is the polymerisation product of a polymerisable mixture that comprises the following components:

• a) a macromer of formula C ##STR32## wherein Macro is an m-valent radical of a polysiloxane or fluorinated polyether from which the number m of groups R.sub.x --H has been removed, each R.sub.x, independently of the others, is a bond, --O--, --NRN.sub.N -- or --S-- wherein R.sub.N is hydrogen or lower alkyl,
• PI* is a bivalent benzoyl radical of a photoinitiator comprising a structural unit of the formula ##STR33## wherein OH/NR'R" indicates that the carbon atom carries either an OH group or an NR'R" group, and R' and R" are each independently of the other linear or branched lower alkyl that is unsubstituted or substituted by C.sub.1 -C.sub.4 -alkoxy,
• R.sub.aa is the sp.sup.3 carbon radical of the above photoinitiator, and
• m is an integer from 1 to 100;
• b) a copolymerisable hydrophilic vinyl monomer;
• and
• c) a crosslinker.