| 摘要 |
<p>Flexible polyurethane faoms are prepd. by foaming a compsn. comprises (1) a polyol consisting of (a) 50-98 pbw of a polyether polyol or mixt. of such polyols having 2-3 OH gps per mol. and n OH equiv. wt. 900-2300, and (b) 50-2 pbw of a solid polymer of one or more ethylenically unsatd. monomers free from gps reactive with NCO or OH gps, the polymer having a mol. wt. at least 5,000; the polyol compsn. being prepd. by adding (b) in the form of a latex having a particle size 1000-7000 A to (a) and removing water to the extent so that mixt. contains zero to suitable amts required for foaming; and (2) an organic polyisocyanate in amts such that NCO- active H ratio is 0.8-1.5:1. Flexible, highly resilient polyurethane foams having improved physical properties esp. tear strength, tensile strength, elongation and indentation load deflection, are obtained. Foams do not require the use of a 'crosslinker.'.</p> |
