【摘要】 测量了不同氧化深度的三类碳纤维(丙烯腈长丝、丙烯腈碳毡和粘胶碳毡)的低温氮吸附等温线。Pickett修正三参数BET方程能很好地关联这些等温线,三类碳纤维具有不同的n值。应用V—n作图法获得了它们的主要孔结构参数,利用Mp—Wp和D-R—Wp的组合方法获得了它们的孔分布数据。结果指出,总表面积、总孔体积、微孔表面积和微孔体积的大小与碳化温度和碳化原料有关,并且随氧化深度而增加;但非微孔表面积基本保持恒定,约为4—12m~2/g。微孔分布的最可几孔半径随氧化深度增加而减小,各类样品的非微孔分布几乎落在同一条孔分布曲线上。更多还原

【Abstract】 Nitrogen isotherms of three kinds of carbon fiber carrier treated at 450 -550℃ in air for 2 hours were determined. Each of them could be well correlated with Pickett’s three parameters BET equation. Some of their pore structure parameters were obtained by V-n plot and their pore size distributions by Mp-Wp and D-R-Wp methods. The results indicated that their total and micropore surface areas, total and micropore volumes depended on the temperature of carbonization and the precursor of carbon fiber and increased with the weight loss. For mesopore and macropore surface areas, however, all had a value of 4- 12m2/g irrespective of the amount of weight loss. It was evident that these represented the roughness of external surface. Micro-pore size distribution curves of these three samples were similar, but the maximum of the curves were different from each other. Their mesopore size distributions estimated by Wp method all fell on the same curve.更多还原