SHEET AND BLOCK FOR REDUCING VIBRATION USING VISCOELASTIC COMPOSITION

摘要

A viscoelastic vibration damping sheet for reducing the noise of an apartment house, and a viscoelastic vibration damping block using the sheet are provided to reduce viscosity, to improve storage modulus and loss coefficient and to enhance heat insulation and soundproofing property. A viscoelastic vibration damping sheet comprises 20-42 wt% of bitumen; 12-32 wt% of a styrene-butadiene latex containing 60-70 wt% of a solid part and having a pH of 8.0-10.5, a surface tension of 30-35 dyne/cm, a viscosity of 800 cps or less and a specific gravity of 0.90-0.99; 12-32 wt% of a styrene-butadiene latex containing 40-59 wt% of a solid part and having a pH of 8.0-10.5, a surface tension of 35-50 dyne/cm, a viscosity of 100-200 cps and a specific gravity of 1.0-1.1; 2-4 wt% of an emulsifier; 6-8 wt% of a softener comprising 5-25 wt% of an aromatic hydrocarbon, 35-55 wt% of a naphthene-based hydrocarbon and 35-45 wt% of a paraffin-based hydrocarbon; 1-3 wt% of an antifoaming agent; and 15-20 wt% of an inorganic filler.