Study on Synthesis and Properties of MDI-50 Type Polyurethane Elastomer

MDI-50,polyol and 3,3′-dichloro-4,4′-diamino-diphenylmethane(MOCA) chain extender were used to prepare MDI-50 type polyurethane elastomer.The effects of the mass fraction of free-NCO in prepolymer and molecular weight of polyol on mechanical properties of the elastomer were studied.The structure and performance were analyzed by means of differential scanning calorimeter(DSC),Thermo gravimetric analysis(TG),Fourier transform infrared(FTIR) spectroscopy and mechanical properties test.And it was compared with TDI-80 type polyurethane elastomer.The results showed that the comprehensive properties of MDI-50 type polyurethane elastomer were better than TDI-80 type polyurethane elastomer.The hardness,tearing strength and tensile intensity of MDI-50 type polyurethane elastomer increased with the increase of the mass content of free-NCO in prepolymer.When the molecular weight of polyol increased,the elongation at break of the elastomer increased.