Flexible resilient flame-retardant and intumescent polyurethane foam is prepared from a reaction mixture comprising a polyether polyol, an organic polyisocyanate, a blowing agent, a surfactant, a catalyst, a flame-retardant and hydrated alumina; the amount of flame-retardant is 30 to 160 parts by weight/100 parts of the polyol. Preferably, the mixture also comprises a low-viscosity linear polyester. In a preferred embodiment, the hydrated alumina is predispersed in a mixture comprising the flame-retardant and a low-viscosity linear polyester; in another preferred embodiment, a char former and/or a fugitive viscosity modifier is/are included.
柔性弹性阻燃和膨胀聚
氨酯泡沫由反应混合物制备而成,该混合物包括聚醚多元醇、有机多
异氰酸酯、发泡剂、表面活性剂、催化剂、阻燃剂和
水合氧化铝;阻燃剂的用量按重量计为 30 至 160 份/100 份多元醇。混合物最好还包括低粘度线性聚酯。在一个优选的实施方案中,
水合氧化铝预先分散在由阻燃剂和低粘度线性聚酯组成的混合物中;在另一个优选的实施方案中,还包括一种
炭化剂和/或逸散粘度调节剂。