Fractionnement et Distribution Moléculaire du Diacétate de Polyoxyméthylène

The fractionation of a polyoxymethylene, stabilized by controlled degradation with acetolysis, has been carried out by two techniques: fractional precipitation and fractional dissolution. Infrared spectroscopy combined with end-group analysis and intrinsic viscosity measurements in aniline at 116.5°C. have been used for the identification of the fractions. The results follow a Mark-Houwink-Sakurada viscosity law and permit the determination of the molecular weight distribution.