PAN基碳纤维纺丝原液的均一性和分散性研究

HOMOGENEITY AND POLYDISPERSITY OF THE PAN--BASED CARBON FIBER SPINNING SOLUTIONS

运用动态流变手段，通过绘制logG′-logG″图和测定体系的凝胶点，对不同温度和非溶剂含量的PAN／DMSO／H2O体系的均一性和分散性进行了研究，并通过凝胶点的测定对体系所处的状态进行了验证。结果表明，当水含量为5％时，体系在60℃～70℃之间由均一液态转变成均一凝胶态；对于水含量不同的其他体系，70℃时均未发生凝胶化转变，依然处于均一的溶液态。通过理论分析，实验采用的常规分子量和较高浓度的PAN溶液均匀稳定，呈现单分散性，是较为理想的纺丝原液。

The homogeneity and polydispersity of PAN/DMSO/H2O spinning dopes with conventional PAN molecular weight and comparative high PAN concentration had been investigated by using rheology method. The homogeneity and polydispersity of PAN/DMSO/H2O was reflected through log G′--log G＂ plot as well as gel point tcmperature gained from the crossover of G′ and G＂. For system with 20% PAN and 5% H2O,the PAN dope at 70℃ and 80℃ belongs to solution state and 50℃ and 60℃ belongs to gel state. At 70℃, all samples belong to solution state. The theoretical analysis indicates PAN/DMSO/H2O system with conventional PAN molecular weight is close to mono--disperse systems,whieh is very suitable for gel spinning.