The invention relates to an elastic polyurethane foam having a resonance frequency of up to 3.5 Hz and a process for producing same. This foam is lobtained by using as main reactant materials at least one polyol selected from among specific polyoxyalkylene polyols and polymer dispersion polyols based on said polyoxyalkylene polyols as the matrix land a polyisocyanate compound. This foam is produced by using a polyoxyalkylene polyol having a particularly low hydroxyl value (X mg KOH/g) and a particularly low total unsaturation (Y meq/g) or a polymer dispersion polyol based on said polyoxyalkylene polyol as the matrix. More specifically the polyoxyalkylene polyol has a hydroxyl value (X mg KOH/g) of 5 to 38 and a total unsaturation (Y meq/g) of up to 0.07, with the proviso that Y ≤ 0.9/(X-10). A preferred polyoxyalkylene polyol is one containing 70 wt.% or more oxypropylene groups and 5 wt.% or more oxyethylene groups. The use of a small amount of a crosslinking agent together with the polyoxyalkylene polyol is preferred. This foam has vibration properties suited for seat cushions of automobiles. Therefore, it can give a comfortable ride.
本发明涉及一种共振频率高达 3.5 赫兹的弹性聚
氨酯泡沫塑料及其生产工艺。这种泡沫塑料是通过使用至少一种选自特定聚氧亚烷基多元醇的多元醇和基于所述聚氧亚烷基多元醇的聚合物分散体多元醇作为主要反应物材料,并以多
异氰酸酯化合物为基体,从而获得的。使用羟值特别低(X 毫克 KOH/克)、总不饱和度特别低(Y meq/克)的聚氧烷基多元醇或以上述聚氧烷基多元醇为基质的聚合物分散体多元醇作为基质,可以产生这种泡沫。更具体地说,聚氧亚烷基多元醇的羟值(X 毫克 KOH/克)为 5 至 38,总不饱和度(Y meq/克)最高为 0.07,但 Y ≤ 0.9/(X-10)。优选的聚氧亚烷基多元醇是含有 70 wt.% 或更多氧
丙烯基团和 5 wt.% 或更多氧
乙烯基团的多元醇。在使用聚氧烷基多元醇的同时,最好使用少量的
交联剂。这种泡沫塑料具有适合汽车坐垫的振动特性。因此,它能带来舒适的乘坐体验。