加压氧化对抑制中间相沥青纤维氧化粘连并丝的影响

Effect of Oxidization-Stabilization under Pressure on Inhibiting the Adhesion of Mesophase Pitch Fibers

为了解决中间相沥青纤维氧化稳定化过程中由于纤维表面发生小分子挥发以及低分子质量组分软化导致的粘连并丝问题,采用加压空气和加压氧气对中间相沥青纤维进行氧化稳定化热处理,研究氧气分压和氧化气体的总压力对沥青纤维氧化粘连的影响。利用悬垂度的测试表征氧化沥青纤维的粘连程度,悬垂度越大说明纤维粘连程度越小。结果表明:空气中压力由0.10 MPa增至2.60 MPa时,氧化沥青纤维束的悬垂度由6%增加到82%;纯氧气氛下压力从0.40 MPa提高到0.60 MPa时,纤维束的悬垂度从42%提高到68%。分析表明,氧分压的提高起到抑制粘连的主要作用,而在相同氧分压下,总压提高也有利于降低粘连。另外加压氧化的方式有效地提升了氧化沥青纤维的均匀性。

Filaments in a mesophase pitch fiber tow could adhere to each other during the oxidization-stabilization process due to the volatilization of small molecules and softening of low molecular components.In order to solve this problem,pitch fibers are oxidized in air and oxygen under different pressures,and the adhesion of oxidized fibers are studied.The adhesion degree of oxidized pitch fibers is characterized by drape degree test.The greater the drape degree,the smaller the adhesion degree.The results show that in air,when the pressure increase from 0.10 MPa to 2.60 MPa,the drape degree of oxidized pitch fibers increase from 6%to 82%,while in oxygen,when the pressure of pure oxygen increased from 0.40 MPa to 0.60 MPa,the drape degree of oxidized pitch fibers increase from 42%to 68%.It is concluded that the increase of oxygen partial pressure plays a major role in the inhibition of adhesion,and the increase of total pressure with the same oxygen partial pressure is also beneficial to reduce adhesion.In addition,the homogeneity of oxidized pitch fiber can be improved by pressurized oxidation.