The dispersion behaviour of different carbon-based nanofillers in deionized (DI) water was investigated in the study at hand by using polycarboxylates as surfactants. Carbon nanotubes (CNTs), carbon black (CB) and expanded graphite (EG) were firstly characterized in respect of their morphology. Subsequently, they were dispersed in DI water using two polycarboxylate (PCE) comb-type copolymers which differed in length of their chemical backbones. Optical microscopy and light transmission analysis during centrifugation disclosed a clear difference in the dispersibility among the nanofillers under investigation. Small CB particles showed excellent dispersion in DI water even with no surfactant. CNT was dispersed significantly better than EG, whereby the PCE with the longer backbone yielded better filler dispersion in both cases. After incorporating the carbon nanofillers into a cementitious matrix, interestingly, the highest compressive and flexural strengths at an early age were measured for the CNT samples with worse filler dispersion. This effect is explained by the role of the PCE and the aspect ratio of the carbon nanofiller, both of which determine the microstructure in the hardened cement-based matrix collaboratively.

通过使用聚羧酸盐作为表面活性剂，在手头的研究中研究了不同碳基纳米填料在去离子（DI）水中的分散行为。碳纳米管（CNTs），炭黑（CB）和膨胀石墨（EG）首先在形态上得到了表征。随后，使用两种聚羧酸酯（PCE）梳型共聚物将它们分散在去离子水中，所述聚羧酸酯的化学主链长度不同。离心过程中的光学显微镜和透光分析表明，正在研究的纳米填料之间的分散性存在明显差异。即使没有表面活性剂，小的CB颗粒也显示出在去离子水中的优异分散性。CNT的分散性明显好于EG，因此在两种情况下，具有较长主链的PCE均具有更好的填料分散性。将碳纳米填料掺入水泥基中后，有趣的是，对于填料分散性较差的CNT样品，在早期发现了最高的抗压强度和弯曲强度。PCE的作用和碳纳米填料的长径比可以解释这种效果，两者共同决定了水泥基硬化基体的微观结构。