发明名称 |
PROCESS FOR THE PRODUCTION OF SOLUBLE HIGH MOLECULAR WEIGHT POLYURETHANES WHICH ARE FREE FROM ISOCYANATE GROUPS |
摘要 |
<p>AN IMPROVED PROCESS FOR THE PRODUCTION OF SOLUBLE HIGH MOLECULAR WEIGHT POLYURETHANES WHICH ARE FREE FROM ISOCYANATE GROUPS of the Invention This invention relates to an improved process for the production of high molecular weight polyurethanes which are free from isocyanate groups and are soluble in organic solvent in reduced reaction times. The reactants, polyol and isocyanate, for example, are mixed together with solvent and the temperature is permitted to rise under the effect of the heat of reaction. The reaction mixture is then cooled with solvent addition in such a way that the viscosity of the reaction mixture remains constant until the optimum temperature for the polyurethane formation reaction ("specific reaction temperature") is reached. The mixture is then gradually cooled until there is no residual isocyanate present and the polymer is recovered from the reaction mixture.</p> |
申请公布号 |
CA1052043(A) |
申请公布日期 |
1979.04.03 |
申请号 |
CA19760249657 |
申请日期 |
1976.04.06 |
申请人 |
BAYER AKTIENGESELLSCHAFT |
发明人 |
NIEDERDELLMANN, GEORG;KLUSSMANN, HENNING;CONRAD, HORST |
分类号 |
C08G18/00;C08G18/08;(IPC1-7):08G18/08 |
主分类号 |
C08G18/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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