Polymerization of <scp>D</scp>‐α‐methylbenzyl methacrylate by <i>n</i>‐butyllithium and the tacticity and optical rotation of the polymer

Abstract

Abstract D ‐α‐Methylbenzyl methacrylate, [α] = +51.3° (neat), was polymerized by n ‐butyllithium in toluene–tetrahydrofuran mixtures of various solvent ratios at −78°C. The polymers obtained were converted into poly(methyl methacrylate)s, which were analyzed for tacticity by high resolution NMR spectroscopy. A linear relationship was obtained between the optical rotation and the isotacticity of poly( D ‐α‐methylbenzyl methacrylate). The extrapolation of the data gave +120° and +99° for [α] of the fully isotactic and syndiotactic polymers, respectively. The copolymerization of the D ‐ and L ‐isomers in toluene gave copolymers which were less isotactic than the homopolymer of the D ‐isomer. The optical rotation of the copolymer was proportional to the excess of one isomer in the polymer.