Flame Retardance For Rice Straw Polyurethane Foam

Rice straw was used to produce rice straw liquefication with liquefying technology of our laboratory.The liquefied rate of rice straw liquefication is 55%,hydoxyl value is 450mg/g.We found that liquefied product is polyether full of hydroxyl,so it could replace polyether polyol to react with isocyanate to produce polyurethane.A physically-bLown polyurethane foam is made with liquefied rice straw as raw materials,we toke tertiary amine catalyst PC5 and PC8 as co-catalyst.We prePared polyurethane foam at different formula,including Pantane content,the proportion of co-catalyst,and foam stabilizer amount was tested,and tested their mechinical properties.Test results shows that the most optimum formula was confirmed by Material Testing Machine,.And we make use of FT-IR and SEM to investigate foam's chemichal structure surface morphology.The test results show the best formula of rice straw polyuthane is:foaming dosage 3%,catalyst dosage 2.5%,catalyst ratio PC5PC8=45,foaming stablizer dosage 4%.And this formula,relative tensile strengTh is 8.07 KPam3Kg-1,relative compression strength is 4.21 KPam3Kg-1,Which confirms rice straw liquefication can replace polyol to make polyurethane foam.For the polyuthane foams are badly in need of better flame retardancy,some phosphrous flame retardants,melamine,nano TiO2 and kaolin as flame retardants were selected as flame retardant addictives to improve the flame retardancy of polyurethane foam.By the combination analysis of results from LOI test,TG test,TG-IR test,char morphology of char layer.We found that melamine nano and kaolin can enhance the intensity of char layer and combination of melamine and phosphrous flame retardants can behave better than single additives.