PURPOSE: The titled composition which has excellent vibration damping properties and is useful as a damping layer of a composite metal plate for vibration damping comprising a non-crystalline thermoplastic resin and a crystalline thermoplastic resin which are not compatible with each other.
CONSTITUTION: The titled composition comprising 10W95wt% non-crystalline thermoplastic resin (A) and 90W5wt% crystalline thermoplastic resin (B) which are not compatible with each other. Resin A has a relatively lower glass transition point of -50W150°C and a maximum tanδ of 0.5 or higher in the frequency range of 0.1W20,000Hz. Resin B has a melting point higher than the glass transition point of resin A and modulus of rigidity of 1×108dyne/cm2 or higher at the temperature and frequency at which resin A has a maximum tanδ. The use of this composition as a damping layer in a composite metal plate for vibration damping will give good damping performance up to a higher temperature than using resin A alone.
ITSUBO AKIRA
WATANABE YUKICHI
SEKIZUKA NORIHIRO
NIPPON KOKAN KK