| 摘要 |
This invention is directed to a process for producing flame retardant flexible polyurethane foams having a porosity generally in the range between 0.5 and 10 cubic feet per minute. A polyol having an average molecular weight between about 250 and about 6,500, preferably about 3,500 to 6,500, is reacted with a polyisocyanate, such as toluene diisocyanate, which comprises a mixture of 2,4- and 2,6-toluene diisocyanate isomers. The formulation of the present invention includes a flame retardant mixture of a plasticizer and dibromoneopentyl glycol. The plasticizer is either a halogented phosphonate or halogenated phosphate ester. Chlorine is the preferred halogen atom. The weight ratio of those ingredients is between about 20/80 and about 90/10. The concentration of that mixture is in excess of about 20 to about 60 percent by weight of the polyol. Other ingredients that can be included in this formulation are water, a silicone surfactant, a tertiary amine catalyst, a tertiary amine co-catalyst, an auxiliary blowing agent and a tin catalyst. This process results in foam products that are flame retardant, suitable for automotive and furniture applications, and have low flame spread indices according to the Radiant Panel Test ASTM E 162-78.
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