in the foregoing disclosure is not to be limited either in spirit or scope by these examples those skilled in the art will readily understand that known variations of the conditions and processes of the following preparative procedures can be used to prepare these compositions unless otherwise noted all temperatures are degrees celsius and all parts and percentages are parts by weight and percentages by weight respectively 2004 g of a hydroxy polyether based on trimethylolpropane propylene oxide and ethylene oxide having a molecular weight of 6000 and 126 g of a hydroxy polyether based on bisphenol a and propylene oxide having a molecular weight of 560 as well as 9 g of trimethylolpropane were reacted with 2162 g of desmodur u00ae w 4 4 u2032 diisocyanatodicyclohexylmethane commercially available from bayer ag at 100 u00b0 c to 110 u00b0 c until the calculated nco content of 14 5 wt was reached 4 g of dibutyl phosphate were added and the excess 4 4 u2032 diisocyanatodicyclohexylmethane was removed by means of thin layer evaporation at 150 u00b0 c to 180 u00b0 c under a pressure of 0 1 mbar the prepolymer had a viscosity of 20 000 mpa u00b7 s at 23 u00b0 c a specific nco content of 2 65 wt and thus an equivalent weight of 1585.