碳前驱体CH_3ArCH_2NH_2的热解性能及动力学研究

Studies on Pyrolysis Properties and Kinetics of Carbon Matrix Precursor CH_3ArCH_2NH_2

通过密闭压力容器法、常压DSC、高压DSC及紫外分光光度定量分析法等实验手段 ,对液相沉积法制碳 /碳复合材料用碳前驱体CH3ArCH2 NH2 的热裂解行为进行了研究 ,获得不同温度、不同压力下该碳前驱体的热分解温度和残碳率 ,用等温动力学和非等温动力学方法获得了热裂解反应的表观活化能 .实验结果表明 ,常压热裂解温度大约为 5 30 15～ 5 5 6 5 5K ,1～ 3MPa的高压范围内的热裂解温度大约在 6 18 34～6 75 49K ;密闭压力容器中的残碳率为 5 6 2 3 % ,常压下的残碳率为 2 8 96 %～ 36 47% ,而高压下残碳率可达 5 9 11% ;根据基辛格等方法获得了等温条件下和非等温条件下热裂解反应的表观活化能Ea 分别为2 0 6 78kJ/mol和 183 93kJ/mol,反应级数n≈ 1.

Pyrolysis behavior of carbon matrix precursor CH_3ArCH_2NH_2 used for preparing C/C composites by rapid densification process was investigated by closed-pressure-vessel method, DSC, high-pressure DSC methods and ultraviolet spectrophotometric method. The pyrolysis temperatures and carbon residual ratios of the compound at different temperatures and different pressures were derived and the apparent activation energy was also obtained by isothermal dynamic and non-isothermal dynamic method. The experimental results are as follows: at the atmospheric pressure, the pyrolytic temperature is about 530.15—547.15 K; at the pressure as high as 1—3 MPa, the pyrolytic temperature is about 618.34—675.49 K. The carbon residual ratios in the closed pressure vessel, at the atmospheric pressure and at a high pressure are 56.23%, 28.96%—36.47% and 59.11% respectively. Based on Kissingers method and the result of isothermal experiment, the apparent activation energies of the pyrolysis reaction under the isothermal and non-isothermal conditions are 206.78 kJ/mol and 183.93 kJ/mol respectively, and the reaction order \{n≈1\}.