PAN纤维碳化裂解的TG-FTIR联用分析

Analysis of pyrolysis for PAN fiber using TG-FTIR

利用TG-FTIR联用分析仪,结合气相裂解质谱,采用国产PAN原丝经预氧化后在200~1350℃范围进行了裂解产物分析。结果表明：PAN预氧化纤维热裂解起始温度在300℃左右,在366.2、624.2和868.0℃出现3个失重速率峰。从纤维中脱除的主要物质如CH_4、NH_3、CO_2、C2H_2等小分子气体产物,同时也包含少量具有较高沸点结构复杂的芳香类物质。裂解产物种类和含量与碳化裂解温度密切相关,其中产生NH_3和C2H_2的裂解温度为380℃,CH_4在480℃出现峰值,CO_2在整个碳化过程均有产生,并且在320、840和1260℃出现峰值。PAN预氧化纤维热裂解的质谱分析很好地验证了TG-FTIR分析结果。

Pyrolysis of stabilized PAN fibers under N2 at 200~1350℃ was analyzed using TG-FTIR and PyGC.The pyrolysis began at around 300℃.Three peaks at 366.2,624.2and 868.0℃ were found in the DTA curve,which indicating fast loss of weight for fibers at these temperatures.The main products of pyrolysis were CH_4,NH_3,CO_2,C2 H and some aromatic molecules.The type and amount of pyrolysis products was strongly temperature dependant.Most of NH_3 and C2H_2was get off from the fibers at 380℃,and CH_4 was at 480℃.The production of CO_2 can been seen at whole carbonization pyrolysis,and three get-off peaks can been seen at 320,840 and 1260℃.PyGC results conformed well with the TG-FTIR analysis.