Free radical copolymerization of novel methacrylates with acrylonitrile and determination of monomer reactivity ratios

p-methoxyphenoxy and p-chlorophenoxy group containing methacrylate based monomer 2-(p-methoxyphenoxy)-2-oxoethyl methacrylate (pMPOEMA) and 2-(p-chlorophenoxy)-2-oxo-ethyl methacrylate (p-ClPOEMA) were synthesized by reacting p-methoxyphenyl chloroacetate (pMPClAcO) and p-chlorophenyl chloroacetate (pCIPClAcO) with sodium methacrylate in acetonitrile respectively. (pMPClAcO) and (pClPClAcO) were prepared by reacting p-methoxyphenol and p-chlorophenol dissolved in benzene with chloroacetylchloride. The free-radical-initiated copolymerization of (pMPOEMA) and (pClPOEMA) with acrylonitrile (AN) were carried out in 1,4-dioxane solution at 65 degrees C using 2,2'-azobisisobutyronitrile (AIBN) as an initiator with different monomer-to-monomer ratios in the feed. The monomers and copolymers were characterized by FTIR, H-1- and C-13-NMR spectral studies. The copolymer compositions were evaluated by nitrogen content in polymers. The reactivity ratios of the monomers were determined by the application of Fineman-Ross and Kelen-Tudos methods. The analysis of reactivity ratios revealed that pMPOEMA and pClPOEMA are more reactive than AN, and copolymers formed are statistically in nature. The molecular weights (M ($) over bar (W) and M ($) over bar (N)) and polydispersity index of the polymers were determined using gel permation chromagtography. Thermogravimetric analysis of the polymers reveal that the thermal stability of the copolymers increases with an increase in the mole fraction of AN in the copolymers. Glass transition temperatures of the copolymers were found to decrease with an increase in the mole fraction of AN in the copolymers.