Effects of phosphorus oxychloride and phenylphosphonic dichloride on the radical polymerization of methyl methacrylate and styrene

Abstract

AbstractEffects of pentavalent phosphorus compounds on the radical polymerization of methyl methacrylate (MMA) and styrene (St) were studied. Phosphorus oxychloride (Cl3PO) and phenyl‐phosphonic dichloride (C6H5Cl2PO) were used. Polymerization was carried out in benzene at 50°C by the standard solution method, α,α′‐azobisisobutyronitrile (AIBN) being used as the initiator. In the polymerization of MMA, both phosphorus compounds increased the rate of polymerization. NMR spectral data suggested that this increasing effect was due to the complex formation between each phosphorus compound and MMA monomer. In the case of polymerization of St, NMR data also indicated the formation of a complex between the phosphorus compound and St monomer. Both phosphorus compounds showed an increasing effect for the rate of polymerization. Though these increasing effects could be explained by the complex formation, the polymerization of St in the presence of Cl3PO was especially found to be due to the cationic polymerization initiated simultaneously by Cl3PO in addition to the radical polymerization. These phosphorus compounds acted as chain‐transfer agents in both polymerization systems. The parameters (Qtr,etr) which indicate the reactivity of a chain‐transfer agent were calculated from the observed values of chain‐transfer constant for both polymerization systems.