| 摘要 |
A prepolymer having an NCO content of less than 10%, based on the reaction of (a) diisocyanate with (b) polyether alcohol, the (b) polyether alcohol comprising (b1) and (b2) and/or (b3) with the following meanings for (b1), (b2) and (b3): (b1) polytetrahydrofuran having a molecular weight of from 1800 to 2100 g/mol and (b2) polyether alcohol having a molecular weight of from 500 to 7000 g/mol, based on ethylene oxide and/or propylene oxide, and/or (b3) polytetrahydrofuran having a molecular weight of from 800 to 1200 g/mol. |
