Plasticizer containing polyvinyl alcohol granules

摘要

For the thermoplastic processing of polyvinyl alcohol, the processing temperature must be below the decomposition temperature of the polyvinyl alcohol; this is attained by incorporating plasticizers. For preparing a plasticizer-containing granular polyvinyl alcohol wherein the plasticizer is homogeneously distributed, there is used as starting material a granular polyvinyl alcohol consisting substantially of particles having a definite diameter. The plasticizer is incorporated in the presence of a small amount of water insufficient to dissolve the polyvinyl alcohol, and the temperature is adjusted in a definite manner during the mixing operation. Simultaneous presence of fine particles of a high molecular weight organic compound soluble or dispersible in water is advantageous. The plasticizer-containing granular polyvinyl alcohol is suitable for the manufacture of any shaped articles, especially films and sheets.