PURPOSE: To obtain a flexible urethane foam having excellent water absorptivity, water retentivity and durability, by reacting a polyol with a polyisocyanate in the presence of a catalyst, a blowing agent and a specified block or graft polymer.
CONSTITUTION: In a process for producing polyurethane foams comprising reacting a polyol with a polyisocyanate in the presence of a catalyst, a blowing agent and a water-absorptive material, there is used, as said water-absorptive material, a block and/or graft copolymer consisting of hydrophobic segments and hydrophilic segments. A variety of combinations of hydrophobic segments and hydrophilic segments can be used as the water-absorptive materials, but those combinations are particularly preferred which have a sequence of (hydrophobic segment)-(hydrophilic segment)-(hydrophobic segment).
HORIGUCHI SHIYOUJIROU
NAKAMURA MICHIEI
TAKIZAWA MINORU
SAKAMOTO SHIGERU
| JPS5175796A | 1976-06-30 | |||
| JPS5437199A | 1979-03-19 | |||
| JPS53138500A | 1978-12-02 |