Removal of residual ethylene oxide from poly(ethylene oxide)

Abstract

Residual ethylene oxide is removed from poly(ethylene oxide) by the steps of adding to particles of high molecular weight poly(ethylene oxide) a finely divided solid particulate material which is capable of coating the poly(ethylene oxide) particles and impeding their agglomeration under conditions of heating, heating the particles of poly(ethylene oxide) at a temperature of at least 40.degree. C. and preferably which is near their crystalline melting point, and maintaining the temperature for a sufficient time to reduce the ethylene oxide in the particles of poly(ethylene oxide) to ten ppm or less. In one embodiment, the poly(ethylene oxide) is heated by holding the particles in a heated enclosure; in another, it is heated as a slurry in a liquid medium; in yet another, it is heated by warm gas in a gaseously-fluidized bed; and in a fourth, it is heated by microwave radiation.

Dependencies are inferred from the claim text.