Copolymerization of 2-Ethyl Hexyl Acrylate with Styrene in the Presence of Zncl2

A copolymer of 2-ethyl hexyl acrylate-styrene was prepared in the presence of ZnCl 2 . The formation was studied by infrared spectroscopy. A study of the final copolymer as a function of the initial monomer composition as well as observation of the variation in intensity of the carbonyl peak from UV spectra confirmed the presence of an alternating copolymer. Solubility trials showed that no homopolymer was formed. The copolymer was characterized by IR, NMR, and solubility tests. It is suggested that the polymerization proceeds through a two-step polymerization mechanism: by coordination followed by polymerization on the alternating copolymer of the chain ends of the residual styrene. The reactivity ratios of the comonomers were determined and found to be 0.3 and 0.04 for the 2-ethyl hexyl acrylate/styrene system.