The study of the structure and polymerization of the products of pyrolysis of α, α′-dichloro- p-xylene and of α, α′-dibromo- p-xylene by electronic and IR spectroscopy

Abstract

A study has been made of electronic and IR spectra of αα′-dichloro- p-xylene, αα′-dibromo- p-xylene, their pyrolysis products trapped at liquid nitrogen temperature and of the final reaction products at room temperature. It was shown that the intermediate pyrolysis product is p-xylylene. The data obtained indicate that the pyrolysis proceeds selectively, via 1,6-dehalogenation. The polymer formed as the final reaction product has a poly- p-xylylene structures. Increasing the pyrolysis temperature (⩾750°) results in the formation of stilbene units. Also, under these conditions, the solid-state polymerization of p-xylylene at −180 to −195° was observed.