Synthesis Of Melamine Intrinsic Structural Flame Retardant Polyether Polyols And Its Research In The Polyurethane Rigid Foam

In this paper, for the insufficient of higher price, bigger viscosity, the synthesis reaction must be carried out under high temperature and high pressure of the structural flame retardant polyether polyol, the intrinsic structure flame retardant polyether polyol which with lower cost, higher-fire-retardant properties had been developed. Further, polyurethane rigid (PUR) foam with efficiently and lasting flame retardant also be manufactured.Firstly, melamine and formaldehyde, epichlorohydrin were used as the main raw materials, and melamine intrinsic structure flame retardant polyether polyol (MFRP polyol) had been synthesized through mannich reaction, anionic ring-opening polymerization. FTIR and’H-NMR all showed that the molecular structure contains the characteristic absorption peak of triazine ring and ether linkage. Effect of the ratio of the reactant, pH value, polymerization temperature and time on the properties of MFRP aslo be system studied. Results showed that the pH value between 7.5-8.0, glycerol as coinitiator, polymerization reaction under the condition of 85℃ for 24 h, viscosity and yield of MFRP polyol are 4583 mPa.S/25℃,93.4%, respectively. Then, MFRP polyol was uesd as the resin to manufacture intrinsic structure flame retardant PUR foam, which the foam has good cell structure, and the oxygen index of it can achieve to 24.2% without adding any flame retardant.Second, low molecular weight phenolic resin was introduced into in the molecular structure of MFRP polyols, thus the melamine-phenolic intrinsic structure flame retardant polyether polyol (MPFRP polyol) which with lower cost, higher-fire-retardant properties had been synthesized.Finally, MPFRP polyol was uesd as the resin cooperate with foaming agent (foam catalyst, blowing agent, flame retardant, isocyanate) to manufacture PUR foam based on the principles of formula design. And effect of different foaming components on the properties of PUR foam had been system studied. The results showed that the oxygen index of MPFRP based PUR foam can reach to 29% and the viscosity can be reduced by adding 25wt% flame retardant (TCPP/DMMP), and the heat-resisting performance also be improved.