Shanghai Yu Hao Chemical Technology Co., long shelf Yanshan Petrochemical (Yanhua) butyl butyl IIR1751 Yanhua 1751: Butyl rubber is a copolymer of isobutylene and isoprene little reason made of synthetic rubber, referred to as IIR, ghts relative molecular mass (35-45) Χ104. Relative density (17 ℃ / 4 ℃) 0.92, (27 ℃ / 4 ℃) 0.91, the refractive index of 1.5078-1.5081, glass transition temperature -69 ℃, the specific heat capacity 1.94kJ / (kg.K). Isoprene link only 0.6% to 3.0% of the main chain, and therefore high saturation butyl rubber molecular chain. Butyl rubber, low permeability, air tightness, which is about 10 times NR, heat aging resistance, temperature vulcanized butyl rubber used up to 150 ℃ -200 ℃. An energy vibration and shock absorbing properties, good damping properties. Tear resistance and excellent electrical insulating properties. Good ozone resistance and aging resistance, excellent resistance to degradation. Disadvantages of butyl rubber is low intensity, low elasticity, poor adhesion. Butyl rubber domestic brands have IIRI751, IIR1751F, IIR0745, IIR1675, which is equivalent to Germany IIR1751 301, Russia 1675N. Quality Indicators Project butyl rubber IIR 1751 EB 165 EB 268 PB 301 Mooney viscosity of 46 ~ 5629 ~ 3546 ~ 5645 ~ 56 Volatile% ≤ 0.3 0.3 0.3 Relative density ash% ≤ 0.3 0.92 0.92 viscosity average molecular weight Χ104 56 35 45 no saturation% (mol) 1.5 1.2 1.5 1.8 Tensile Strength MPa≥ 16.2 17.2 16.4 15.2 Elongation% ≥ 500 650 550 450