| 摘要 |
PURPOSE:To obtain the titled foam having high gas-permeability, formability and physical properties and sufficient heat-weldability, by using a polyol composition containing a modified polyol produced by reacting a specific diol having low molecular weight, etc., with a specific amount of a polyisocyanate. CONSTITUTION:A modified polyol is produced by reacting a mixture of (A) 50-97wt.% (based on the sum of the components A-D) polyether polyol having an OH value of 25-170, (B) a diol containing secondary OH group and having a molecular weight of <=200 (e.g. di- or trioxypropylene glycol) and, if necessary, (C) a mono-ol or a polyol other than the component B and having an average molecular weight of <=1,000 with (D) 0.3-1.2 times equivalent of a polyisocyanate based on the sum of the components B and C. The obtained modified polyol is optionally diluted with (E) a polyol having an OH value of 28-120 and the obtained polyol composition is made to react with (F) a polyisocyanate in the presence of a foaming agent, a catalyst, etc.
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