Polymerization of methyl methacrylate with the use of cetyl trimethyl ammonium bromide-benzoyl peroxide combination as the initiating system

Methyl methacrylate (MMA) was polymerized at 40 in the presence of dimethyl formamide (DMF), using cetyl trimethyl ammonium bromide with benzoyl peroxide (CTABBZ₂O₂) as the initiating system. At high dilutions the rate of polymerization was proportional to (initiator)^1–2. In near-bulk conditions using low [DMF], the rate was practically independent of [BZ₂O₂], while the kinetic order with respect to CTAB was about 0.16. The polymerization was inhibited by hydroquinone. A radical mechanism is suggested for the polymerization with primary radical termination significant in near-bulk systems and bimolecular termination significant for high dilution with DMF. Effects of various other solvents or additives on the polymerization were examined. DMF, acetonitrile and pyridine act as rate accelerating diluents; benzene, methanol, chloroform and acetone as inert diluents; formamide and acetamide cause pronounced retardation.