Research Of Properties And Prediction Of Using Age Of GF/UPR Immersing In Hydrothermal Environment Condition

Glass fiber unsaturated polymer resin owns a lot of fascinating properties, such as high strength with low density, high specific modulus, excellent weather fastness resistance, good design ability and low cost. Those characteristics contribute to the application of GF/UPR in lots of fields, for example, aerospace industry, aviation industry, architecture industry and transportation industry. More and more fiber reinforced composites has been used in city heating pipes. Because the using conditions of heating pipes are always of high temperature and constant humidity. This paper has conducted the following researches.In the view of Si O2 and unsaturated polyester resin cannot connect well. This paper through certain technical means and control, showed by infrared detection which fully proves the presence of organic key group in the modified nano-silica by silane coupling agent KH570. The particles gain a wonderful dispersion, meanwhile KH570 can provide a connection point between Si O2 and the UPR. The use of nano-particles properly can improve the glass-transition temperature of the pure resin. When the mass fraction of the modified Si O2 is 6%, the glass-transition temperature is 12 ℃ higher than the pure unsaturated polyester resin. After that, the higher the mass fraction of the particle is, the lower the glass-transition temperature of the resin is. And the modified resin gets better mechanical properties.The glass fiber reinforced unsaturated polyester resin panels can be manufactured through winding technology. Moisture diffusion and mechanical properties of GF/UPR composites have been investigated by immerging thin specimens in water with high temperature. The materials get saturation differently in different temperature conditions. Tensile strength, tensile modulus, bending strength and shearing strength present decay law separately. Taking strength for example, the shearing strength decreases mostly in 85 ℃ and reaches 37.88%, the bending strength gets 30.23%, while the tensile strength is 30%. The SEM photograph shows that moisture mainly destroys the interface of the material.With the help of the test data and the doseresp equation, we get tensile strength, bending strength, shearing strength attenuation curve of the GF/UPR composites. Finally we have used tensile strength predicting equation to predicted the lifetime of the materials.