PURPOSE: To form the titled copolymer which still retains inherent characteristic properties of a polyamide resin and is excellent in water resistance, water absorption resistance, and chemical resistance, by linking a polyamide polymer with a polysiloxane polymer through a suitable urethane bond.
CONSTITUTION: Use is made of at least one polysiloxane (number-average MW of 200W20,000) of formula I , II, or III (wherein M is alkylene, phenylene, or oxyethylene, R is H, methyl or phenyl, n is 0W50, and t, p, and q are each 0W5). Namely, a polyamide (number-average MW of 500W10,000) having a dicarboxylic acid or a diamine on each end, obtained by the polycondensation of a 2W15C lactam (or an α,ω-amino acid) or the polycondensation of a 2W15C dicarboxylic acid with a diamine, is linked with the above polysiloxane via a compound having at least two isocyanato groups (e.g., tetramethylene diisocyanate).
TOKA YUUZOU
IKEDA NAOKI
