反应详情

The polyurethane polymer of Example 2 is prepared from a mixture of the ingredients in the amounts listed in Table 1, wherein Polyol A, Isocyanate A, and Catalyst A are as identified in Example 1. Surfactant A is an organosilane surfactant degassing agent commercially available form Union Carbide Corp. under the trade designation L-5304. Isocyanate B is a mixture of methylene diphenyldiisocyanate with tripropylene glycol and dipropylene glycol, having an average molecular weight of 364, commercially available from The Dow Chemical Company under the trade designation Isonate 181. Polyol B is a polyether triol of 2600 molecular weight formed from a heterofeed mixture of 50 weight percent ethylene oxide and 50 weight percent propylene oxide commercially available from The Dow Chemical Company under the trade designation Polyglycol 15-200. Polyol C is a 400 molecular weight polyether having about 100 weight percent oxyethylene groups and a nominal functionality of 2. The mixture is vacuum degassed for 2 minutes. Then, Isocyanate A is mixed into the mixture to form an admixture which is degassed for and additional 2 minutes. The admixture is poured into a open steel mold which is maintained at a temperature of 50° C. for a period of 8 hours, after which it is placed in an oven at 180° F. for a period of 24 hours.