Enhancement of Vicker's hardness of nanoclay-supported nanotube reinforced novel polymer composites

摘要

Carbon nanotubes as a reinforcement engineering material in polymer composites holds the promising potential for low-weight composites of extraordinary mechanical, electrical, and thermal properties. The size scale, high aspect ratio, low density, and other exceptional properties of nanotubes are generally advantageous when they are applied in a variety of applications. However, in the case of nanotube-reinforced polymer composites, there has only been a moderate strength enhancement that is significantly below the theoretically predicted potential 1. To achieve the full reinforcing potential of nanotubes, there remains two critical issues that have to be firstly solved, (i) the dispersion of nanotubes in a polymer matrix and (ii) the inter-facial bonding between the nanotubes and the polymer matrix. In general, weakly interacted nanotube bundles and aggregation of nanotubes would result in a poor dispersion state that significantly reduces the aspect ratio of the reinforcement 2. The reason for the weak interfacial bonding behavior lies in the atomically smooth, non-reactive surface of the nanotubes that cannot ensure efficient load transfer ability from the polymer matrix to the nanotube lattice 3. To solve this problem, a number of methods have been developed to maximize the benefits of nanotubes in polymer composites, i.e. surfactant assisted dispersion 4, sonication with high power 5, in situ polymerization 6, electric field or magnetic-induced alignment of nanotubes 7,8, plasma polymerization 9, and surface modification such as inorganic coating 10, polymer wrapping 11, as well as protein functionalization 12.