| abstract |
PURPOSE: To obtain a preformed fiber polyisocyanurate composite having high rigidity, high heat resistance, rapid curability and a short molding cycle, by preparing an RIM reaction solution by using a specified polyol and a specified mixing ratio of an organic polyisocyanate to a polyol. n CONSTITUTION: The preparation of an RIM reaction solution is performed so that the two following requirements may be met: (1) a single or mixed polyether-polyol of a hydroxyl value of 40W400 is used as the polyol and (2) of the mixing ratio of the organic polyisocyanate to the polyol is controlled so that the isocyanurated isocyanate concentration [NCO]T defined by the equation I may fall in the range of 3.0W5.5mmol./g, wherein [NCO]T is the theoretical concentration (mmol./g) of an isocyanate consumed in a isocyanuration, [NCO]O is the isocyanate concentration (mmol./g) of the organic polyisocyanate, OH-V is the hydroxyl value of the single or mixed polyol, and WA is the weight fraction of the organic polyisocyanate. n COPYRIGHT: (C)1988,JPO&Japio |