混合锆类粉体对高模量碳纤维表面改性的研究

Surface modification of high modulus carbon fiber by mixed zirconium powders

混合锆类粉体是含有锆元素的无机陶瓷材料。采用溶胶-凝胶法与碳热还原法制备得到了ZrO_(2)、ZrB_(2)、ZrC、ZrN混合锆类陶瓷粉体,并利用连续上浆工艺将其涂覆到碳纤维表面。采用X射线衍射仪对锆类粉体进行了结构与组分的分析。通过扫描电子显微镜、热重测试研究了混合锆类粉体的加入对碳纤维表面形貌、耐热性能的影响。结果表明,实验条件下制备混合锆类粉体的最佳原料配比是n(Zr)∶n(B)∶n(C)=1∶2.5∶12,粉体的最佳烧结温度为1600℃,此时粉体中ZrB_(2)含量相对最多;高模碳纤维经过10%粉体上浆改性后,碳纤维的起始氧化温度从675.1℃升高到了717.9℃,氧化反应的表观活化能从76.41kJ/mol升高到115.43kJ/mol。

Mixed zirconium powders are inorganic ceramic materials containing zirconium elements.Mixed zirconium ceramic powders-ZrO_(2),ZrB_(2),ZrC and ZrN were prepared by sol-gel and carbothermal reduction methods,and were coated onto the carbon fiber surface using continuous sizing process.The structures and components of mixed zirconium powders were analyzed by X-ray diffractometer.The effects of the addition of mixed zirconium powders on the morphology and heat resistance of carbon fibers were studied by scanning electron microscope and thermogravimetric analyzer.The results showed that the optimum experimental conditions for synthesis of mixed zirconium powders were as follows:sintering temperature was 1600℃,and material ratio was n(Zr)∶n(B)∶n(C)=1∶2.5∶12,when the ZrB_(2)content in the powders was relatively the most.After being modified by 10%powder sizing,the initial oxidation temperature of carbon fibers increased from 675.1℃to 717.9℃,and the apparent activation energy of oxidation reaction increased 76.41kJ/mol to 115.43kJ/mol.