with the other polymerizable components to provide a non leachable lens as illustrated in detail herein below their synthesis may involve preparing a pdms free radical macroinitiator followed by polymerization in the presence of n vinyl pyrrolidone or other polar vinyl or acrylic monomers susceptible to free radical polymerization in the presence of a cta chain transfer agent such as ipa isopropoxyethanol or mercaptoethanol to generate the oh u2014 functionalized polymer the resulting polymer may be methacrylated using different chemistries by reacting the oh group with methacryloyl chloride or methacrylic anhydride in the presence of a base or alternatively by reaction with isocyanatoethyl methacrylate using this approach a variety of methacrylate ma functionalized pdms polar copolymer blocks can be synthesized examples of materials of interest are pdms pvp maa and pdms polynipaam ma the chemistry may also be extended to prepare difunctional methacrylate functionalized triblock copolymers such as ma pvp pdms pvp ma and other polymers starting with commercially available dihydroxy or diamino functionalized polydimethylsiloxanes persons skilled in the art are familiar in general with the production of block copolymers having functionally active endgroups for instance u s pat no 5 589 563 polymer technology group the disclosure of which is herein incorporated by reference discloses how to make and use functionalized copolymers the synthesis of meth acrylate functionalized pvp is achieved by a methacrylation reaction of hydroxy functionalized pvp that is prepared using reactions known to those.