Potato Starch Encapsulation with Polyethylene. I. Catalysis and Polymerization

Abstract

A process for the encapsulation of individual potato starch granules with polyethylene is described. It involves a thorough dessication of starch followed by a generation of a fine precipitate of VCl₃ which adsorbs on the surface of each granule. When this deposit of VCl₃ is activated by Al(C₂H₅)₃, the surface of the granule becomes active toward polymerization of ethylene. An encapsulation of each individual granule by polyethylene is obtained when the polymerization occurs in a non solvent. The growth of the encapsulation shell is studied as function of time, temperature, catalyst concentration and moisture content of the starch samples.