| 摘要 |
Flame resistant polyurethane foams are produced from polyisocyanates and organic compounds with reactive hydrogen atoms by foaming with water and/or other blowing agents in the presence of red phosphorus. The red phosphorus may be used in combination with halogen containing organic and/or inorganic compounds. Suitable polyisocyanates are diisocyanated, a crude diphenyl-methane-4,41-diisocyanat being used in the examples. Triisocyanates such as toluene 2:4:6-triisocyanate may also be used. The preferred compounds containing reactive hydrogen atoms are (A) a polyester prepared from adipic acid, phthalic acid, oleic acid and trimethylolpropape, (B) an addition product of trimethylolpropane and propylene oxide with OH number = 380, (C) as for (B) but with OH number = 550, and (D) N,N,N1,N1-tetrakis-(hydroxypropyl) ethylene diamine. Other blowing agents are halogenated alkanes such as trichloromonofluoromethane and compounds which decompose to split off nitrogen, such as azodiiso-butyric nitrile. Suitable halogen containing compounds are antimony and arsenic halides, ammonium halides, halogenated castor oil or tall oil, halogenated hydrocarbons, esters of hexachloro - endomethylene - tetrahydrophthalic acid, pentabromo - diphenyl ether and organic compounds containing phosphorus atoms in addition to halogen in the molecule. Suitable catalysts are tertiary amines and organic tin compounds. The red phosphorus may be added in amounts of 0.05 to 20% by weight of the mixture to be foamed. |
