气相生长碳纤维在水泥基材料中的分散性研究

以脱油沥青(DOA)为原料,采用化学气相沉积法(CVD)制备出气相生长碳纤维(VGCFs).利用硬化试件电阻测试法和硬化试件断面形貌法.测试了VGCFs增强水泥的电阻率、变异系数和断面扫描电镜形貌,考察了3种不同制备工艺下VGCFs在增强水泥复合材料中的分散性.结果表明,先将分散剂、消泡荆、VGCFs在水中预分散再加入超细矿粉和水泥的搅拌工艺分散效果最好,干混法与湿混法较差.采用合理的制备工艺(预分散法),当VGCFs掺量为0.2%(体积分数)时可制得纤维均匀分散、电阻率小、变异系数小的VGCFs增强水泥.

Study on the Dispersion of Fibers in Cement Reinforced with VGCFs

VGCFs are prepared from de-oiled asphalt(DOA) by chemical vapor deposition(CVD). Based on the measurements of the resistivity, the variation coefficient and scanning electron microscopy(SEM) fractographs for the specimen. The influence of different preparation processing on the dispersion of carbon fiber in cement reinforced with VGCFs are studied. The results indicate that using dispersant and defoamer for pre-dispersion, together with proper manufacturing technology, the dispersion of VGCFs in cement can be improved, compared to the corresponding other two methods. VGCFs reinforced cement is carried out by reasonable preparation process( pre-dispersion method) when VGCFs dosage is 0. 2%,and its fibers distribute evenly, resistivity and coefficient of variation is small.