SEMIAROMATIC POLYAMIDE, SEMIAROMATIC POLYAMIDE RESIN COMPOSITION, AND MOLDED ARTICLE

摘要

The purpose of the present invention is to provide: a semiaromatic polyamide which has excellent heat resistance, chemical resistance and mechanical characteristics, while exhibiting moldability that is suitable for various component materials for automobiles and the like; and a molded article of this semiaromatic polyamide. A semiaromatic polyamide (I) of the present invention contains 35-50% by mole of a structural unit derived from terephthalic acid [A], 25-40% by mole of a structural unit derived from isophthalic acid [B], 15-35% by mole of a structural unit derived from an aliphatic dicarboxylic acid [C] (provided that the total of [A], [B] and [C] is 100% by mole), and a structural unit derived from an aliphatic diamine [D] having 4-12 carbon atoms. The molar ratio ([A]/[B]) is from 65/35 to 50/50, and the molar ratio ([C]/[B]) is from 30/70 to 50/50. The melting enthalpy (∆H) of the semiaromatic polyamide (I) as determined by differential scanning calorimetry (DSC) is 20-40 mJ/mg, and the limiting viscosity [&eegr;] of the semiaromatic polyamide (I) is 0.7-1.6 dl/g.