Microcombing enables high-performance carbon nanotube composites

A processing approach, microcombing, has been reported recently to produce dry carbon nanotube (CNT) films with superior mechanical and electrical properties by taking advantage of its efficiency in straightening the wavy CNTs and aligning the strands. Here, we report the fabrication of CNT composite films with aligned CNTs and CNT strands, reduced waviness, high CNT weight fraction, and relatively uniform CNT distribution, using poly(vinyl alcohol) (PVA) as a model matrix. These structural features give the micro-combed CNT/PVA composite films electrical conductivity of 1.84 × 105 S/m, Young's modulus of 119 GPa, tensile strength of 2.9 GPa, and toughness of 52.4 J/cm3, which improve over those of uncombed samples by 300%, 100%, 120%, and 200%, respectively, and are also much higher than those obtained by other processing approaches. Moreover, this method is expected to be applicable to various polymer matrices as long as they can be dissolved in the solution.