METHOD FOR PRODUCING A THERMOPLASTIC COMPOSITION BASED ON POLYVINYL ALCOHOL FREE OF UNFUSED MATERIAL AND DEGRADATION

摘要

The invention concerns a method for producing by milling-melting-extrusion a thermoplastic composition based on at least a polyvinyl alcohol, comprising also at least an agent for plasticizing said polyvinyl alcohol, characterized by the complete core absorption of the plasticizer by polyvinyl alcohol crystals before melting or extrusion. In accordance with said method, the resulting composition is free of physico-chemical degradation of the polymer by heat shock producing yellowing and free of unfused material as well. Said method enables to obtain gels, granules or articles made from granules of excellent quality.