| 摘要 |
Reaction products, from diphenylmethane-2,4'-diisocyanate with a fraction of at least 95 wt. % of 2,4' isomer with at least one polyether polyol and/or polyalkylene glycol with a molecular weight of less than 1,000 and/or a crystalline or part-crystalline, or glassy amorphous polyester polyol and, optionally, polyester polyols and/or polyether polyols with a molecular weight greater than 1,000, which are liquid at room temperature, can be reacted to give adhesive compositions with a very low content of residual monomeric diisocyanate of less than 0.5, preferably less than 0.25 wt. %. Said hot-melt adhesive compositions comprise, in addition to the low content of monomeric diisocyanate a high fusion stability and a low viscosity. |
