Synthesis and Characterization of Poly(allyl methacrylate) Obtained by Free Radical Initiator

Allyl methacrylate was polymerized in CCl₄ solution by α,α′‐azoisobutyronitrile at 50, 60, and 70°C. The kinetic curves were auto‐accelarated types at 60 and 70°C, but almost linear at 50°C. Arrhenius activation energy was 77.5 kJ/mol. The polymer was insoluble in common organic solvents. It was characterized by FT‐IR, NMR, DSC, TGA and XPS methods. About 98–99% of allyl side groups were remained as pendant even after completion of the polymerization. The spectroscopic and thermal results showed that polymerization is not a cyclopolymerization type, but may have end group cyclization. The high molecular weight is the main cause of a polymer being insoluble even in the early stage of the polymerization. Molecular weight of 1.1×10⁶ for a soluble polymer fraction was measured by light scattering method. The Tg of polymer was 94°C, and after curing at 150–200°C, increased to 211°C. The thermal pyrolysis of polymer at about 350°C gave an anhydride by linkage type degradation, and side group cyclization. The XPS analysis showed the presence of radical fragments of AIBN (initiator) and CCl₄ (solvent) associated with oligomers.