CATALYSED POLYMERIZATION OF METHYL METHACRYLATE IN THE LIQUID PHASE

Abstract

USING benzoyl peroxide as catalyst, Norrish and Brookman1 found thatthe order of the polymerization reaction of undiluted methyl methacrylate is approximately zero in the first stages ; the initial rate of reaction is proportional to the square root of the catalyst concentration2.The rate of reaction was found to rise markedly after about 10-20 percent polymerization, and at the same time considerable heating of the system took place. Norrish and Brookman supposed that the temperature rise caused the rate increase, the former arising from a decrease of thermal convection in the system with increasing viscosity during polymerization. After experiments on catalysed and uncatalysed reactions, Schulz and Blaschke3 took the opposite view, namely, that the rate increase mainly caused the temperature rise, and supposed that the former was due to an increase in the rate of initiation of active centres.