| 摘要 |
PURPOSE:To provide an insulating polybutadiene-based urethane casting resin composition which is especially suitable for a joint part of an electric wire cable, excellent in disassembling property, fire retardant property and electric characteristics and low in water absorbability as well as hardly generating cracks to heat fluctuation. CONSTITUTION:100pts.wt. liquid polybutadiene polyol with a MW of 700-8,000, 20-150pts.wt. diluent inactive to an isocyanate group (e.g.; a process oil), 10- 100pts.wt. halide (e.g.; hexabromobenzene) and 40-200pts.wt. alumina hydrate are mixed to obtain solution I. The resulting solution I and solution II comprising an isocyanate compound are mixed in such a ratio that an equivalent ratio of an active hydrogen and an isocyanate group is 0.7-1.2 and poured into a mold and cured by a conventional method. As the isocyanate compound of the aforementioned solution II, an isocyanate-terminated prepolymer obtained by reacting an excessive isocyanate with a liquid polybutadiene polyol is especially preferred. |
