Abstract The development of carbon structures in mesophase pitch fibers was studied with controlling the initial temperature (Ti) of the stabilization process to optimize the mechanical properties of final carbon/graphite fibers. To understand the relationship between Ti and chemical structural change by thermostabilization, the pitch fiber was thermally treated from various Tis up to 350 °C with an elevation rate of 2 °C/min. Various analyses of the oxygen species in the fiber revealed that changing Ti governed the amount and distribution of oxygen in the stabilized fibers, while determining the effective duration of thermostabilization and preserving hydroxyl groups originally present in the precursor fiber. Among various samples, stabilized fibers with Ti of 150 °C contained the largest amount of oxygen in the fiber, resulting in the highest degree of polyaromatic inner structure after the subsequent carbonization and graphitization to show the best tensile strength and modulus. We also demonstrated that the optimal mechanical, electrical, and thermal properties of the resulting graphite fiber were comparable to those of commercially available fiber products (XN-80-60s), indicating that Ti should be carefully considered to enhance the properties of carbon and graphite fibers.

中文翻译：

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通过调节初始稳定温度提高中间相沥青基石墨纤维的物理性能

摘要 通过控制稳定化过程的初始温度 (Ti) 来优化最终碳/石墨纤维的机械性能，研究了中间相沥青纤维中碳结构的发展。为了通过热稳定了解 Ti 与化学结构变化之间的关系，将沥青纤维从各种 Tis 热处理至 350 °C，升温速率为 2 °C/min。对纤维中氧物质的各种分析表明，改变 Ti 控制了稳定纤维中氧的数量和分布，同时确定了热稳定的有效持续时间并保留了最初存在于前体纤维中的羟基。在各种样品中，Ti 为 150 °C 的稳定纤维在纤维中含有最多的氧，在随后的碳化和石墨化后产生最高程度的多芳烃内部结构，以显示最佳的拉伸强度和模量。我们还证明了所得石墨纤维的最佳机械、电学和热学性能与市售的纤维产品 (XN-80-60s) 相当，表明应仔细考虑 Ti 以增强碳和石墨的性能纤维。