Preparation Of Casting Polyurethane Elastomer Composites And Their Properties

We need a large number of composite materials with good abradability, water resistance and properties of reduction of vibration and noise when empoldering marine resources. Polyurethane elastomer (PUE) composites have not only higher strength, good abradability, medium resistance, damping properties but also 30 years of life, so it is a kind of interesting and valuable composite.In this paper, the casting PUE composite was synthesized by prepolymerizing. The reaction mechanism was discussed by FT-IR spectra, and the microstructure and morphology were characterized by XRD and SEM. The macroeconomic performances were characterized by the electronic universal testing machine, viscoelastic apparatus and permeability cup.First of all, the preparation conditions of the HTPB PUE were studied. The best batch formula was obtained by comparing the static mechanical properties of the composite materials. When the prepolymer was synthesized with hydroxyl-terminated polybutadiene 2600 as soft segment, 2, 4-toluene diisocyanate as hard segment, 4.9%～5.0% of -NCO, DADMT/TMP (1:1) as mixed chain extender, equivalent coefficient of 1.1 and 10% of DPB, the mechanical properties of the PUE material were the best.Second, the modification of the PUE was also studied. The linear polymer and functional fillers were added during the synthesis to improve the mechanical and damping properties of the PUE composites. (1) PU/E-51 composites. The mechanical performance test showed that the mechanical properties of the composite were improved greatly when the amount of E-51 added was 1/3 of the prepolymer. The DMA test implied that, compared with pure polyurethane material, the damping peak of the PU/E-51 substantially moved to the high temperature zone, and the damping temperature zone was widened too. (2) PU/piezoelectric ceramic composite. The mechanical performance test showed that the mechanical properties were the best when the amount of the piezoelectric ceramic was 60% of the prepolymer. The DMA measurement showed that the storage modulus and loss modulus of the composite decreased much faster with increasing temperature. While the polyurethane material was modified simultaneously by piezoelectric ceramic and hollow glass microballoon, the heat-resistant property of composite was improved, which leaded to the slow decrease of storage modulus and loss modulus.Finally, the paper also designed a new synthetic method of polyurethane/small organic molecule hybridized damping materials. The XRD patterns indicated that the crystalline structure was formed in the composite when the small organic molecules were added into the reaction system in a fusion state. The DMA test showed that the loss factor was greatly improved after modification and it was higher than before at the temperature range of T> -53℃. The DMA frequency spectra showed that the storage modulus and loss modulus increased faster than before and the maximum value of the loss factor was 0.47. In addition, the storage modulus and loss modulus increased much faster from 0.1 to 100000 Hz.