Novel N-acyloxytrialkylammonium salts as initiators for free radical polymerization of methacrylates

Abstract

An efficient method for preparing and isolating new derivatives of N-acyloxytrialkylammonium salts as initiators for the free radical polymerization of methacrylates and dimethacrylates is reported. The new initiators were evaluated for the free radical polymerization of methyl methacrylate (MMA), triethylene glycol dimethacrylate (TEGDMA) and ethoxylated bisphenol A dimethacrylate (EBPADMA) at 60 °C both with and without sulfuric acid promotion. The resulting polymers were all characterized by TGA and in addition, PMMA was characterized by DSC and SEC. The new initiators are very effective in producing narrow MWDs in PMMA and in effecting crosslinking in the dimethacrylates. The reaction time, polymer yield, molecular weight distribution (MWD), polydispersity index (PDI), decomposition temperature (T_d) and glass transition temperature (T_g), all improved under sulfuric acid promotion at 60 °C. Our attempts at photo-initiated polymerization of the monomers were not successful.