| 摘要 |
<p>Graft polymers, (I), contain (a) 2-4 pts. wt. vinyl phosphonate esters and (b) 0-3 pts. wt. N-contg. ethylenically unsatd. monomer on 100 pts. wt. polyether-polyol having average mol.wt. 1500-10000. The P- and opt. N-contg. (I) are used as flame-proofing agents in prepn. of opt. cellular polyurethanes by reacting (i) polyisocyanates with (ii) sufficient (I) to provide 0.3-1 wt.% P in polyurethane, (iii) further higher- and low mol.wt. cpds. contg. isocyanate-reactive H atoms, opt. in the presence of (iv) blowing agents, catalysts and further additives. Polyalkylene oxide graft copolymers contain esp. 0.6-1 wt.% P and 0.2-0.7 wt.% N, are light yellow, transparent and neutral. (I) have low viscosity and can be added directly to soft foam-producing compsns. Self-extinguishing polyurethanes can be obtd., without loss in cell structure, elasticity, tensile strength and extensibility. In an example, acrylonitrile and imethyl vinyl phosphonate were grafted onto a 95/5 C3H6O/C2H4O polyether.</p> |
