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To improve the performance of unsaturated polyester (UP) under cold-heat alternate temperature, selfsynthesized reactive thermotropic liquid crystalline polymer (TLCP)-methacryloyl copolymer (LCMC), UP, and glass fiber (GF) hybrid composites was prepared by molding technology. The apparent activation energy and crystal behavior analysis of LCMC/UP blends were investigated by Differential scanning calorimetry and X-ray diffraction (XRD), respectively, the results showed that the addition of LCMC can reduce apparent activation energy and accelerate the curing reaction of UP, the XRD analysis indicated that the crystal phase of LCMC still exist in the blends after blending with UP. The effect of LCMC content on the properties of LCMC/UP/GF hybrid composites such as impact strength, bending strength, and ring-on-block wear were also investigated through static mechanical tests and wear tests. The mechanical properties of hybrid composites increased significantly because of the addition of LCMC. The wear tests showed that LCMC can improve the wear resistance of the UP/GF/LCMC hybrid composites even though the content of LCMC was at a relatively low level (5-7.5 wt %). This makes it possible to develop novel kind of UP-based materials with good wear resistance for various applications. The Worn surface was observed by scanning electron microscopy (SEM) and the mechanism for the improvement is discussed in this paper.

In situ hybrid composites of thermotropic liquid-crystalline polymer (TLCP), unsaturated polyester (UP) and glass fiber (GF) have been successfully prepared by melt mixing technology. The mechanical properties and dynamic mechanical properties and the morphologies of these in situ hybrid composites have been studied by static mechanics analysis, dynamic mechanical analysis (DMA) and scanning electron microscopy (SEM). The static mechanical test results showed that the impact strength and the bending strength, bending modulus, specific strength and specific modulus of the in situ hybrid composites tend to increase with the increase of TLCP content for the composites containing TLCP content below 5%. DMA results indicate that the microstructure of curing network, glass transition temperature and obdurability of composites with TLCP content below 5% have been improved. Scanning electron microscope observations revealed that the interfacial adhesion between matrix and fiber had been improved with the addition of TLCP.

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Unsaturated polyester (UP) reinforced with self-synthesised reactive thermotropic liquid crystalline polymer (TLCP)-methacryloyl copolymer (LCMC) and glass fibre (GF), the hybrid composites of UP/GF/LCMC were prepared by moulding technology. The dynamic mechanical analysis indicated that storage modulus and glass transition temperature (T g ) of hybrid composites increased significantly because of the addition of LCMC. The effect of LCMC content on the mechanical properties of LCMC/UP/GF hybrid composites such as impact strength, specific strength and modulus and load-displacement relationship were also investigated through static mechanical tests. The mechanical properties of hybrid composites increased significantly because of the addition of LCMC. The crystal behaviour analysis of LCMC/UP blend was investigated by X-ray diffraction and polarising optical microscopy. The results showed that the crystal phase and texture structure of LCMC still existed in the blends after blending with UP. The morphology of fracture surfaces of hybrid composites containing different TLCP contents was observed by scanning electron microscopy. The present paper discussed the mechanism for the improvement of dynamic mechanical and mechanical properties.