To obtain a polyamide having good transparency, heat resistance, and mechanical strengths, and excellent moldability by selecting a polyamide having at least one type of repeating structural units in the molecule and having a specified logarithmic viscosity.
This polyamide has at least of type of repeating structural units represented by formula I (wherein (m) and (n) are each 0 or 1; R1 is a 2-27C divalent group selected from the group consisting of an aliphatic group, a cycloaliphatic group, a monocyclic aromatic group, a fused polycyclic aromatic group and a non-fused polycyclic aromatic group composed of aromatic groups bonded to each other directly and/or through bridging members; Y1A and Y1B are each H, a 1-4C alkyl, a 1-4C alkoxyl, phenyl, or a halogen) and having a logarithmic viscosity of 0.01-3.0 dl/g. It is prepared by condensing an aromatic diamine component represented by formula II (wherein (m) and (n) are each 0 or 1; and Y9A and Y9B are each H, a 1-4C alkyl, a 1-4C alkoxyl, phenyl or a halogen) with a dicarboxylic dihalide represented by formula III (wherein R10 is the same as R1 in formula I; and X10 and X10B are each a halogen).
OKUMURA TOMOMI
SAKATA YOSHIHIRO
KUROKI TAKASHI
OKAWA YUICHI
OIKAWA HIDEAKI
