Exploiting new comonomers is still required for high performance polyacrylonitrile (PAN) based carbon fiber. In this paper, we have proposed an efficient methodology, combining of theoretical calculation and experimental verification, to develop new comonomer for polyacrylonitrile (PAN)-based carbon fiber. The cyclization energy barriers of PAN copolymers, including comonomers of α-nitryl acrylic acid (IA-NO₂), α-amino acrylic acid (IA-NH₂), acrylamide (AAM), itaconic acid (IA), and ethylenesulfonic acid (ESA), have been calculated based on the autocatalytic cyclization mechanism using density functional theory (DFT) at B3LYP/6-31 + G (d, p) level. The theoretical calculation indicated that ionic cyclization of nitrile group was more easily initiated by ESA than other comonomers. Correspondingly, the PAN copolymers including comonomers of ESA and IA have been prepared and studied on their properties. The experimental results further demonstrated the P(AN-co-ESA) copolymer had better thermal properties such as smaller cyclization energy, slower heat release rate, and higher char yielding. Therefore, this theoretical calculation combined with experimental verification methodology is a powerful tool for exploiting new comonomer for PAN-based carbon fiber.

高性能聚丙烯腈（PAN）基碳纤维仍需要开发新的共聚单体。在本文中，我们提出了一种有效的方法，将理论计算和实验验证相结合，以开发用于聚丙烯腈（PAN）基碳纤维的新型共聚单体。PAN共聚物的环化能垒，包括α-腈丙烯酸（IA-NO ₂），α-氨基丙烯酸（IA-NH ₂）的共聚单体），丙烯酰胺（AAM），衣康酸（IA）和亚乙基磺酸（ESA）是基于B3LYP / 6-31 + G（d，p）级的基于密度泛函理论（DFT）的自催化环化机理计算的。理论计算表明，与其他共聚单体相比，ESA更容易引发腈基的离子环化反应。相应地，已经制备了包括ESA和IA的共聚单体的PAN共聚物并对其性能进行了研究。实验结果进一步表明，P（AN-co-ESA）共聚物具有较好的热性能，例如环化能较小，放热速率较慢，焦炭产率较高。因此，这种理论计算与实验验证方法相结合，是开发用于PAN基碳纤维的新型共聚单体的有力工具。