METHOD FOR PRODUCING BARRIER MATERIAL EXCELLENT IN HEAT STABILITY

PROBLEM TO BE SOLVED: To provide a method for producing a material, capable of improving molding stability and heat aging characteristics of the material, by preventing a decrease in a molecular weight of an aliphatic polyester caused by reaction thereof with moisture in air, when molded, and further capable of improving water vapor permeability and oxygen permeability of the material which is required as a container packaging material. SOLUTION: This method for producing the material comprises adding an aromatic dicarboxylic acid or its derivative in a molar ratio of 0.005-0.15 based on a total mole of an aliphatic diol and an aliphatic dicarboxylic acid in a polycondensation process of the aliphatic polyester, so as to obtain a prepolymer (A), then binding the prepolymer (A) to a polyamide (B-1) and/or a polyamide dispersion composite (B-2) which is formed by dispersing the polyamide in an intercalation compound of an alkyl onium salt intercalated in expansive clay mineral through blocking reaction, so as to produce the block material or the block composite material. Further, the method has a process in which the material or the composite material is made to have a higher molecular weight through the blocking reaction by using at least one kind of a diisocyanate, a diepoxy compound, and a compound having a dioxazoline ring. COPYRIGHT: (C)2006,JPO&NCIPI