首页>
外国专利>
The water expansible hard form where the mechanical characteristics in low temperature improve
The water expansible hard form where the mechanical characteristics in low temperature improve
展开▼
机译:水可膨胀的硬形式,在低温下的机械特性得到改善
展开▼
页面导航
摘要
著录项
相似文献
摘要
The present invention relates to a rigid polyurethane foam which can be obtained by mixing (a) isocyanates, (b) compounds having groups which are reactive toward isocyanates, (c) blowing agents comprising water, (d) catalysts and optionally (e) further additives to form a reaction mixture, applying the reaction mixture to a reinforcing material and curing the reaction mixture, where the isocyanates (a) have a viscosity of not more than 500 mPas at 25° C. and the compounds (b) having groups which are reactive toward isocyanates comprise a polyetherol (b1) having a functionality of 4 or more and a viscosity at 25° C. of 10 000 mPas or less, a polyetherol (b2) having a functionality of 3.5 or less and a viscosity at 25° C. of 600 mPas or less, a polyesterol (b3) having a viscosity at 25° C. of 2000 mPas or less, chain extenders (b4) comprising at least 30% secondary OH groups and optionally a crosslinker (b5). The present invention further relates to a process for producing such rigid polyurethane foams and the use of the rigid polyurethane foams for the insulation of liquefied natural gas tanks.
展开▼