炭纤维层间化合物的制备及其膨化(英文)

PREPARATION OF INTERCALATION COMPOUNDS OF CARBON FIBERS AND THEIR EXFOLIATION

在浓硝酸溶液 (13mol dm3)中 ,通过恒电流电解 ,成功地进行了中间相沥青和聚丙烯腈基两种炭纤维(MPCF ,PANCF)的硝酸插层。虽经水洗和干燥后有部分被分解成残余化合物 ,但从其层间距增至 0 .78nm左右这一现象证实已形成了层间化合物。经急剧加热至 10 0 0℃后 ,观察到了显著的形貌变化 ,单根纤维沿着纤轴被劈裂开 ,转变成一束微纤维。低结晶度PAN CF经急热处理后 ,被观察到了这种膨化现象。对经 2 0 0 0℃左右处理的MPCF ,在两个阶段 ,电解时CF的电势明显增加 :15 0 0℃处理的MPCF电解电势逐渐增加 ,而 115 0℃处理的MPCF 。

Intercalation of nitric acid into mesophase pitch based and PAN based carbon fibers was successfully carried out by electrolysis of the fibers using a constant current in a concentrated nitric acid solution of 13?mol/dm 3. Formation of intercalation compounds was confirmed from the fact that the interlayer spacing increased to about 0.78?nm, though a fraction decomposed to the residual compounds after rinsing and drying. After rapid heating to 1?000?℃, a marked morphological change was observed, a single fiber being converted to a bundle of thin filaments split along the original fiber axis. For PAN based carbon fibers with low crystallinity, the exfoliation was observed after rapid heating. Potential change of carbon fibers during their electrolysis markedly increased in two steps for mesophase pitch based carbon fibers heat treated above 2?000?℃. For carbon fibers treated at 1?500?℃, however, potential increased gradually, with almost no increase for those treated at 1?150?℃.