聚丙烯腈热稳定化纤维的裂解行为

在聚丙烯腈基碳纤维(PANCF)制备过程中会有40%~50%的质量损失,主要发生在300~800℃范围内。对PAN裂解失重行为的研究有利于理解PANCF类石墨结构的形成机理,为制备高性能碳纤维和提高碳化收率提供理论依据。通过热重分析法(TGA)模拟PAN纤维的裂解失重过程,结果表明:在空气中进行稳定化的纤维主要有两个阶段的裂解,分别受腈基的环化率和氧含量控制。环化率和氧含量通过影响裂解行为在碳纤维中形成的缺陷结构,最终影响碳纤维的致密性。环化率越高,形成的缺陷结构越少,碳纤维的致密性越好;相反氧含量越高,形成缺陷结构越多,碳纤维的致密性越差。

Degradation Behavior of Thermal Stabilized Polyacrylonitrile Fibers

In the temperature range of 300-800℃,40％-50５ of the mass lost during the processing of polyacrylonitrile based carbon fiber (PANCF).Understanding the degradation behavior will be valuable in understanding the formation mechanism of pseudo-graphite structure,and providing theoretic basis for producing high performance carbon fiber and increasing the carbonization yield.The simulation of the degradation progress was carried out on the thermogravimetric analyzer (TGA),the results show that there are two degradation steps for PAN fiber stabilized in air,and controlled by cyclization coefficient and oxygen content.The cyclization coefficient and oxygen content are effective to the density of carbon fiber by influencing the degradation behavior,which cause defects in the fiber.The higher cyclization coefficient leads to form less structural defects and higher density of the fiber;on the contrary,the higher oxygen content leads to form more structural defects and lower density of the fiber.