Polymerization of 3,3‐bis (chloromethyl) oxetane catalyzed by i‐Bu3Al in bulk. I. The conditions of high polymer formation

Abstract The high temperature (up to 220°C.) polymerization of 3,3‐bis(chloromethyl)oxetane catalyzed by i ‐Bu 3 Al was investigated. The conversion‐time curves are of the autocatalytic type and the molecular weight increases lineary with conversion up to the point at which for lower temperatures, e.g. 60–80°C., the whole polymer becomes insoluble. An alternative explanation of this phenomenon is proposed; the formation of insoluble product is related to the entanglement of macromolecules of very high molecular weight and or macrocycle formation in the degradative chain transfer to polymer. The phenomenon of insoluble products formation was never observed at higher temperatures (> 150°C.). The dependence of molecular weight on catalyst and impurity concentrations as well as on the polymerization temperature was investigated. It was shown that the high molecular weight product ( \documentclass{article}\pagestyle{empty}\begin{document}$\overline {DP}$\end{document} = 1000–1500) can be produced at 180–220°C. even at rather high impurity level.