聚丙烯腈纤维孔隙结构对预氧化的影响

The influence of pore structure of polyacrylonitrile fiber on the oxidative stabilization

采用湿法纺丝,通过不同的牵伸条件,制备具有相同的化学组分和不同孔隙率(体密度)的聚丙烯腈纤维,然后在相同的条件下预氧化。借助红外吸收光谱(FT-IR)、场发射扫描电子显微镜(FESEM)、差示扫描量热(DSC)等表征手段对原丝和预氧丝的环化度、皮芯结构及预氧丝横截面的氧径向分布进行分析对比。实验结果表明,随着孔隙率降低(体密度增加),纤维径向的氧含量梯度变大,皮芯结构趋于严重。

Polyacrylonitrile （PAN） fibers with different porosities were prepared by wet spinning under different stretching conditions. The fibers were oxidized under the same condition. The influence of the porosity on the pre- oxidation of the PAN fibers was studied by infrared absorption spectrum （FT-IR）, field emission scanning electron microscope （FESEM） and differential scanning calorimetry （DSC） The results show with the porosity decrease （density increase）, the oxygen uptake during oxidation became low, and the gradient of radial oxygen distribution became steeper, which would lead to form serious skin-core structure in the fibers.