Study On Properties And Synthesis Of High Temperature Resistant Glass Fiber Reinforced PA10T1010

PA10T is a new type of high temperature resistant polyamide material developed by the Kingfa SCI.&TECH.Co.,LTD.It has excellent heat resistance,rigidity and dimensional stability.However,the melting point of PA10 T is 315?,which is close to its decomposition temperature,and hence the melt processing window is narrow so as to limit its industrial processing and application.Institute of Macromolecules and Bioengineering in North University of China broadened the processing window of the material on the premise of maintaining the excellent comprehensive properties of the material by the modification of the copolymerization of PA10 T and PA1010.In order to further improve the comprehensive performance and processing performance of PA10T/1010,in this paper,a series of composite materials PA10T1010/GF were prepared by melting and blending different proportion of PA10T1010 and modified glass fiber.And the effects of glass fiber content on the thermal properties,mechanical properties and crystallization properties of PA10T1010/GF composites were studied by differential scanning calorimeter(DSC),thermogravimetric analyzer(TG),dynamic mechanical analyzer(DMA),electronic tensile test machine and pendulum impact tester,respectively.The study of mechanical properties shows that the tensile strength,bending strength,flexural modulus,notch impact strength and non notched impact strength of the composites are obviously improved with the increase of glass fiber content in the composite PA10T1010/GF.When the glass fiber content is 35%,the tensile strength and flexural strength are increased by 426% and 208% respectively.The DMA test showed that the glass fiber enhanced the PA10T/1010 obviously.With the increase of the glass fiber content,the energy storage modulus of the composites increased,the internal friction angle tan delta decreased and the water absorption of composite materials decreased.The thermal properties showed that the thermal deformation temperature of the composite PA10T1010/GF increased significantly with the increase of glass fiber content,making it wider application fields.TG analysis showed that the addition of glass fiber did not change the thermal decomposition mechanism of PA10T/1010,but it improved the thermal stability.DSC and XRD analysis showed that the existence of glass fibers reduced the melting point of PA10T/1010 and improved its processability,but did not change the crystal structure of PA10T/1010.The study of rheological properties showed that both PA10T/1010 and PA10T1010/GF are pseudoplastic fluids,and their non-Newtonian index increases with the increase of temperature.The addition of glass fiber can improve the sensitivity of apparent viscosity to shear stress and shear rate,thus improving the processing properties of the composites.Moreover,with the increase of shear stress,the viscous activation energy of PA10T/1010 and PA10T1010/GF decreases.The isothermal crystallization kinetics of PA10T/1010 and PA10T1010/GF composite were studied by the Avrami equation.The results showed that the crystalline form of PA10T/1010 and PA10T1010/GF both may be the mixture growth with one-dimensional and two-dimensional growth,and the crystallization temperature has little effect on the crystal growth mode.The addition of glass fiber may make PA10T/1010 nucleate along the surface of glass fiber and grow in bundles.The non isothermal crystallization kinetics of the material was studied by Jeziorny method.The results showed that the growth mode of PA10T/1010 and PA10T1010/GF composite crystal at the early stage of crystallization was the mixture growth with two dimensional disk like growth and three dimensional spherulite growth.In the later stage of crystallization,the crystallization rate of polymer becomes slower and the crystallization mode is more complicated.The addition of glass fibers makes the crystallization more complex,which may be caused by matrix PA10T/1010 induces transverse crystal along the surface of glass fiber,but the existence of glass fiber accelerates the rate of non isothermal crystallization.To sum up,PA10T/1010 was synthesized by one step direct melt polycondensation,and the PA10T1010/GF composite with different glass fiber content was prepared by melt blending with glass fiber through a reactive twin screw extruder.Based on the analysis and study of the mechanical properties,thermal properties,rheological properties and crystallization kinetics of PA10T/1010 and PA10T1010/GF,the effects of different glass fiber content on the properties of the composites are obtained,which provides a scientific basis for the industrial application of this kind of materials.