PRECIPITATION OF POLYCYCLOOLEFINS

摘要

Precipitation of a polymer from polymer cement containing about 15 to 80% solids is accomplished by mixing the cement with water and a nonsolvent near or above the boiling point of a ternary azeotrope whereby the polymer precipitates forming a slurry and the ternary azeotrope is withdrawn as a vapor, separating the polymer from the liquid phase and recycling the liquid phase to the mixing step, the polymer cement being a honey-like solution in a nonpolar solvent of a polymer prepared by ring opening polymerization in the nonpolar solvent of at least one cyclic olefin containing at least one norbornene group, the nonsolvent is selected from lower alcohols that form binary azeotropes with water, and the ternary azeotrope comprising the nonpolar solvent, the nonsolvent, and water. The process can be operated either in batchwise segments or continuously throughout.