Non-covalent interactions between carbon nanotubes and conjugated polymers

Abstract

Carbon nanotubes (CNTs) are interest to many different disciplines including chemistry, physics, biology, material science and engineering because of their unique properties and potential applications in various areas spanning from optoelectronics to biotechnology. However, one of the drawbacks associated with these materials is their insolubility which limits their wide accessibility for many applications. Various approaches have been adopted to circumvent this problem including modification of carbon nanotube surfaces by non-covalent and covalent attachments of solubilizing groups. Covalent approach modification may alter the intrinsic properties of carbon nanotubes and, in turn make them undesirable for many applications. On the other hand, a non-covalent approach helps to improve the solubility of CNTs while preserving their intrinsic properties. Among many noncovalent modifiers of CNTs, conjugated polymers are receiving increasing attention and highly appealing because of a number of reasons. To this end, the aim of this feature article is to review the recent results on the conjugated polymer-based non-covalent functionalization of CNTs with an emphasis on the effect of conjugated polymers in the dispersibility/solubility, optical, thermal and mechanical properties of carbon nanotubes as well as their usage in the purification and isolation of a specific single-walled nanotube from the mixture of the various tubes. IntroductionEver-increasing demand for materials with defined functions and properties urge researchers to seek for ways to design and synthesize novel materials. To this end, nanostructured-materials are getting increasing attention owing to their interesting and unusual properties. Among them, the carbon nanotubes (CNTs) are of particular interest to researchers from different disciplines such as chemistry, physics, biology, medicine and engineering because of their extraordinary structural, mechanical and electronic properties and also for their potential applications in many areas including optoelectronics, nanotechnology, nanomedicine, chemical and biological sensing and etc. 1-8CNTs having a cylindrical nanostuctured-shape consist of seamless rolls of graphitic sheets and can be classified as singlewalled nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) depending on the number of graphene sheets they contain as shown in Fig. 1. Diameter of SWCNTs could vary between 0.4 nm and 3 nm while a diameter range of 2-30 nm is characteristic for MWNTs. The length of both SWCNTs and Deparment of Chemistry and Institute of Materials Science and Nanotechnology, Bilkent University, Bilkent, Ankara, Turkey 06800. E-mail: dtuncel@fen.bilkent.edu.tr D€ on€ us Tuncel D€ on€ us Tuncel graduated from University of North London. Then she went on to study her PhD degree at Cambridge University in the Melville Polymer Synthesis Laboratory and after a while she moved to Imperial College, London and completed her study in 1999 under the supervision of Dr Joachim Steinke in the area of supramolecular c...

Carbon nanotube-based antimicrobial biomaterials formed via layer-by-layer assembly with polypeptides

“…However, SWNT properties are known to be highly dependent on surface chemistry, and covalent functionalization alters these intrinsic properties [50]. Non-covalent functionalization of SWNT with amphiphilic molecules such as surfactants, polymers, and biomacromolecules is an alternative method toward SWNT dispersibility, and generally leaves intrinsic properties unperturbed [51,52].…”

Structure of a carbon nanotube–dendrimer composite

“…However, processing CNT´s and introducing them into real applications is severely limited by their low solubilities in organic solvents. In recent past, two general strategies have been explored for improving the CNT solubility: (i) covalent functionalization of sp2 carbons at the sidewalls with organic molecules [18][19][20][21][22][23][24] and (ii) non-covalent functionalization through supramolecular interactions [25][26][27][28][29][30][31][32] (eg. π-π stacking interactions).…”

The Ugi reaction in polymer chemistry: syntheses, applications and perspectives

“…Plenty of methods have been developed to solve this problem, including the conjugation of solubilizer on the CNT surface ('grafting to' method), in-situ polymerization on CNT surface ('grafting from' method), etc. [77][78][79][80][81][82][83][84] . However, most of those methods do suffer from tedious processes, harsh reaction conditions or unsatisfactory solubilization effect.…”