STEREOREGULARITY OF POLY(METHACRYLIC ACID ESTERS).

l-Menthyl methacrylate (l-MnMA) and dl-MnMA and their mixtures were poly merized with benzoyl peroxide (BPO), phenylmagnesium bromide (PhMgBr), and lithium aluminum hydride (LiAlH4), as catalyst. The isotacticity of the polymers of dl-MnMA polymerized with PhMgBr was independent of the polymerization temperature and low. The tacticity of the polymers from the mixtures of l- and dl-MnMA's polymerized with BPO hardly changed with monomer compositions, while that with LiAlH4 showed increase with the increase of l-monomer contents. Thechange of the optical activity of PMnMA's with the stereoregularity is slight as compared with large variation of the tacticity of the polymers. Although both in radical and anionic polymerizations preference of one monomer to another monomer does not occur, in isotactic polymerization with LiAlH4 asymmetric induction of menthyl groups on the main chain configurations takes place. The tacticities of some poly(methacrylic acid esters) polymerized with PhMgBr under similar conditions were compared.