COPOLYMERIZED POLYAMIDE RESIN, METHOD FOR PRODUCING SAME, RESIN COMPOSITION, AND MOLDED ARTICLE FORMED FROM THE COPOLYMERIZED POLYAMIDE RESIN OR THE RESIN COMPOSITION

摘要

A copolyamide resin for molding including a diamine component which includes two or more diamines and a dicarboxylic acid component. The diamine component includes 70 mol % or more of a xylylenediamine which includes 20 mol % or more of p-xylylenediamine and the dicarboxylic acid component includes 70 mol % or more of a straight-chain aliphatic dicarboxylic acid having 6 to 18 carbon atoms. The copolyamide resin contains particles having a major diameter of 50 µm or more in an amount of 1000 particles/g or less, the particles being made of a polyamide having a melting point higher than that of the copolyamide resin by 20 °C or more when measured by a differential scanning calorimetry. The copolyamide resin has very uniform and stable properties and is excellent in any of mechanical properties, heat resistance, chemical and physical properties, and molding properties. An efficient production method of the copolyamide resin, its resin composition, and its molded article are also described.