| 摘要 |
PROBLEM TO BE SOLVED: To provide a production method of polyisocyanate polyaddition (PIPA) polyol, to provide the PIPA polyol, and to provide the use method of the PIPA polyol in production of polyurethane.SOLUTION: There is provided a method for producing a polyol comprising a particulate material in dispersed form by reacting an MDI-based polyisocyanate and a polyol having an equivalent weight of up to 400, which reaction is carried out in a polyol having an equivalent weight of 500 or more wherein the polyol having an equivalent weight of 500 or more is a polyoxyethylene polyoxypropylene polyol which has an oxyethylene content of 15-49 wt.% calculated on the total oxyalkylene groups present wherein 20-80% of the oxyethylene groups resides at the end of the polymer chains. |
