Effects of the Heat Treatment on the Mechanical Properties of a Novel Thermotropic Liquid-Crystalline Polymer Fiber

Abstract:

Thermotropic liquid-crystalline polymers (TLCPs) have aroused wide public concern which is attributed to their high strength, stiffness, chemical resistance and perfect dimensional stability as high-performance engineering materials. Vectran heat treated after melt spinning is a representative commercial aromatic copolyester fiber. In this study, a novel TLCP melt-polymerized with 4,4’-diphenyloxide dicarboxylic acid (DODA), 4-acetoxybenzoic acid (ABA), hydroquinone diactate (HQA), 2,6-naphthalene dicarboxylic (NDA) and terephthalic acid (TA) were melt spun into fibers and heat treated to enhance the breaking strength and Young’s modulus. Intermolecular mechanical elements slipped between 120-130 °C and crystallization or the conformational rotations occurred along the extended polymer chain. For this new TLCP fiber, the optimal heat treatment temperature was 260 °C and the suitable heat-treatment time was over 48 hours. The breaking strength, Young’s modulus and breaking elongation of the as-spun fiber were improved from 1.58GPa, 45.21GPa and 1.97% to 3.20GPa, 133.44GPa and 2.42% respectively after heat treatment.

• Periodical: Solid State Phenomena (Volumes 181-182)
• Pages: 63-66
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.181-182.63
• Online since: November 2011
• Authors: Wei Biao Zhu, Hai Xiao Gan, Yuan Yuan Zhuang, Wei Min Qin, Yan Ping Wang, Yi Min Wang
• Keywords: Crystallization, Heat Treatment, Mechanical Property, TLCPs Fiber

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