| 摘要 |
<p>A prepolymer obtainable by polymerising a mixture comprising: (A) an isocyanate component (B) a polyol component comprising one or more rigid foam polyols; and (C) a low viscosity component which is non-reactive towards isocyanate and hydroxyl groups; and subsequently removing free diisocyanate monomer from the prepolymer to a level of less than 2% by weight.</p> |
