PURPOSE: To obtain a thermoplastic resin compsn. excellent in the balance among mechanical strengths, stiffness, and vibration-damping properties by compounding a methacrylic ester (co)polymer and a rubbery polymer having a specified glass transition point.
CONSTITUTION: A thermoplastic resin compsn. is obtd. by compounding 100 pts.-wt. polymer compsn. comprising 40-95wt.% methacrylic ester (co)polymer obtd. by (co)polymerizing 100-40wt.% methacrylic ester and 0-60wt.% other monomer copolymerizable therewith, 60-5wt.% (rubbery) polymer with a glass transition point (measured by differential calorimetry) of -65 to -20°C, and 0-40wt.% other thermoplastic polymer with 0-150 pts.wt. inorg. filler and has a bending modulus (at 25°C) of 15,000kg/cm2 or higher, a loss tangent (-30 to 140 °C) of 0.035 or higher, and a specific damping coefficient [calculated using the formula (wherein δ is a logarithmic decrement obtd. from a vibration damping curve) from vihbation damping characteristics (at a resonance frequency of 300-600Hz)] of 10% or higher.
NAGAHARA NAOJI
FURUYAMA KENJU
