The reduction of carbon nanotube (CNT) length during the manufacture of CNT/polymer composites and a method to simultaneously determine the resulting CNT and interfacial strengths

Carbon nanotube/epoxy composites with an excellent dispersion of carbon nanotubes (CNTs) were prepared using a three-roll calandering technique. CNT length after processing of composites is measured and then characterized using a two-parameter Weibull distribution function. Significant reduction of the CNT length is observed as a result of the processing and it is thus suggested that great attention should be paid to the retention of CNT length after processing in order to obtain good mechanical properties. Because of the difficulties in manipulating nanometer sized CNTs during measurement of CNT strength and CNT–polymer interfacial strength, CNT strength and CNT–polymer interfacial strength have previously been determined using complicated methods with expensive or specially designed equipments. In this work a simple methodology based on the modified rule of mixtures is proposed to simultaneously determine the CNT strength and CNT–polymer interfacial strength.