Characterization of injection-molded high-strength/high-stiffness thermoplastic hybrid materials containing thermotropic liquid crystal polymer (LCP), polyphenylene sulfide (PPS) with carbon fibers

Abstract

In this study, thermotropic liquid crystal polymer (LCP)-based hybrid materials with various carbon fiber (CF) and polyphenylene sulfide (PPS) contents were developed to replace the heavy metal brackets used for liquid crystal displays (LCDs) in thin, light mobile devices. To determine the physical properties of the composite, several characterization methods, including mechanical, thermal, and morphological tests, were used. As the CF content increases, the tensile and flexural moduli also increase because of the high modulus values of CF. However, some strength-related properties, such as the tensile, flexural, and impact strength, decrease because of the lack of interfacial compatibility between the CF and matrix polymers. Additionally, as the thickness of the LCP-based hybrid material decreases, the flexural strength and flexural modulus increase because of the highly oriented characteristics of LCPs at the surface. To improve the interfacial strength between the CF and LCP, epoxy is a good compatibilizer. In addition, PPS can be used to reduce the weld line formation of LCP and improve the processability of LCP-based hybrid materials with high CF contents.