Preparation and Characterization of Poly(2-oxazolidinone)s

Abstract

The polymers containing the 2-oxazolidinone ring in their main chains were synthesized by the polyaddition of p-bis(2-oxooxazolidin-5-ylmethoxy)benzene (PBOB) to diisocyanates by the use of N-methylpyrrolidone and triethylenediamine as solvent and catalyst, respectively. PBOB was prepared by the reaction between tris(2, 3-epoxypropyl)isocyanurate and hydroquinone in the presence of sodium hydroxide as a catalyst in refluxing solution of N, N-dimethylformamide. Three kinds of arylene and alkylene diisocyanates were used in the polyaddition reaction. The polymers, obtained in high yield, were generally soluble in m-cresol and N-methylpyrrolidone. The polymers had inherent viscosities in a range of 0.15-0.64 and gave transpareht films by solution casting. The polymer based upon PBOB and 4-methyl-m-phenylene diisocyanate gave the highest inherent viscosity. A confirmation that the base unit of the polymers contains the 2-oxazolidinone ring was obtained by the similiarity of the infrared spectra for five kinds of analogous monomeric 2-oxazolidinones, and by an elemental analysis. As well as the polymers anchoring the 2-oxazolidinone ring, the poly(2-oxazolidinones) obtained were found to form the complexes with phenol, iodine and bromine. Especially the amount of phenol in the complex increased with the increase in molecular weight of polymers.