CATALYTIC CHAIN TRANSFER POLYMERIZATION (CCTP) OF METHYL-METHACRYLATE- EFFECT OF CATALYST STRUCTURE AND REACTION CONDITIONS ON CHAIN TRANSFER-COEFFICIENT

Catalytic chain transfer polymerisation of methyl methacrylate has bee n investigated by a range of cobalt(II) complexes. The effect of catal yst structure, reaction temperature and solvent has been examined. At 60 degrees C in the absence of solvent, the chain transfer coefficient , Cs, for MMA and cobaloximes modified by bridging BF2 groups e.g. 3 i s found to be 40,900, this is constant over a wide mass range. Cs is l owered when catalysts of larger cross sectional area are used supporti ng a diffusion controlled process. Co-ordinating solvents suppress Cs by competing for coordination of the Co(II) effectively reducing the c oncentration of active species. No conclusions can be drawn regarding the effect of temperature and thus the activation energy of the proces s. CCTP lowers the observed rate of polymerisation.