CRYSTALLIZING METHOD FOR CRYSTALLINE POLY (ALKYLENE CARBONATE) AND NON-CRYSTALLINE POLY (ALKYLENE CARBONATE), AND HIGH OXYGEN SHIELDING HIGHLY TRANSPARENT LAMINATED SHEET AND ITS PREPARATION

摘要

PURPOSE: To raise melt peak temp. while lowering oxygen transition temp. and to facilitate the processing of a multilayered laminated sheet, a flat plate, a pipe or a rod by providing a layer comprising a low oxygen barrier crystalline polymer and an adhesive adjacent layer comprising a crystalline poly(alkylene carbonate). CONSTITUTION: An alkylene constitutional unit consists of 2-8C acrylic hydrocarbon and cyclopropylene regardless of the presence of a 1-4C hydrocarbon substituent. Crystalline poly(alkylene carbonate) is selected from groups wherein the alkylene constitutional unit may be same and different. Herein, the crystalline poly(alkylene carbonate) is pref. poly(ethylene carbonate) and poly(propylene carbonate). Amorphous poly(alkylene carbonate) is stretched at a temp. of 120-150 deg.C lower than the decomposition temp. thereof but higher than the glass transition temp. thereof and this stretching degree brings about the formation of a crystal to crystallize the amorphous poly(alkylene carbonate).