油剂结构与性能对PAN氧化碳化的影响

Effect of structure and properties of spinning finishes on pre-oxidation and carbonization of PAN

采用傅里叶变换红外光谱、元素分析、热重分析和粒径分析等方法研究了2种聚丙烯腈(PAN)纤维纺丝用油剂A和B的结构与热性能,以及油剂对PAN纤维预氧化和碳化过程的影响。结果表明:油剂A和B均为氨基改性硅油,热分解主要发生在模拟低温碳化阶段,油剂B的耐热性较油剂A更好;油剂A和B在模拟低温碳化阶段,其失重率分别为91.1%,81.7%,失重终止温度分别为456,718℃;油剂A和B的粒径分别为406,244 nm,油剂B的上油效果更好;经油剂A和B上油后制得的碳纤维的拉伸强度分别为3.62,4.13 GPa,拉伸模量分别为274,281 GPa;经热稳定性更好的油剂B上油后得到的PAN原丝在模拟氧化碳化过程中能够有效防止纤维热粘连,制备的碳纤维力学性能更好。

The structure and thermal property of two kinds of spinning finishes,A and B,for polyacrylonitrile（ PAN） precursor were studied by Fourier transform infrared spectroscopy,elemental analysis,thermogravimetric analysis and particle size analysis,as was the effect of the spinning finishes on the pre-oxidation and carbonization process of PAN precursor. The results showed that spinning finishes A and B belonged to amino modified silicon oil,their thermal decomposition primarily occurred during the simulated low-temperature carbonization stage,and spinning finish B was better than spinning finish A in heat resistance; the weight loss of spinning finishes A and B were 91. 1% and 81. 7% and their decomposition termination temperatures were 456 and 718℃,respectively,during the simulated low-temperature carbonization stage; the particle sizes of spinning finishes A and B were406 nm and 244 nm,respectively,and spinning finish B provided better oiling effect; the tensile strength of the carbon fiber oiled with spinning finishes A and B was 3. 62 and 4. 13 GPa,and the tensile modulus was 274 and 281 GPa,respectively; and the PAN precursor oiled with spinning finish B with good thermal stability could efficiently avoid the heat adhesion during the simulated pre-oxidation and carbonization stages and contribute better mechanical properties to the carbon fiber thereof.