Carbon nanotubes (CNTs) are ~100 times stronger than steel, lighter than aluminium and ~10 times more conductive than copper. These extraordinary physical properties are an ideal complement for polymers, which are often fragile and typically insulating, but easily processible. Consequently, the reinforcement of polymers with carbon nanotube fillers has been one of the most active areas of research in CNT science and composite materials in general.
However, the improvement in mechanical properties of the CNT-polymer composites remains far behind the theoretical predictions, by several orders of magnitude. These disappointing experimental results are due to a combination of imperfect individualization of the CNTs and poor load transfer from the polymer to the CNTs.
In PINT, we explored the direct connection of the polymer matrix to the macrocycles to form Polymers Interlocked with carbon NanoTubes (PINTs). The PINT strategy addresses all the critical issues for SWNT-polymer composites at the same time: effective control of SWNT-polymer interface through non-covalent but very strong mechanical bonds, SWNT-polymer alignment through control of the number of mechanical bonds per unit length of the composites, and efficient dispersion (“solubilization”) of the SWNTs induced by the presence of the macrocycles. Our results have shown load transfers of 20%-60%, results that have allowed us to establish a longer term research contract with Danish company Nanocore ApS (www.nanocore.com) for three years, to exploit commercial application of PINTs.
