Oxidised multi-wall carbon nanotubes-(R)-polylactide composite with a covalent β-D-uridine filler-matrix linker

Oxidised multi-wall carbon nanotubes (MWCNTs)-(R)-polylactide (PLA) composite was prepared in 85% yield via in-bulk Ring Opening Polymerisation (ROP) of (R,R)-lactide at elevated temperature using a 'grafting-from' technique. Outer nanotube walls were firstly covalently functionalised with a beta-D-ouridine linker-through the more reactive hydroxyl group (5'-OH)-enabling further a direct growth of the polymer from the free secondary hydroxyl groups (2'- and 3'-OH) present in the beta-D-ribofuranose moiety. The morphology and chemical structure of the composite were comprehensively studied revealing a high-quality MWCNT-filler dispersion and loading of ca. 7 wt%, accompanied by a high molecular weight (Mw) of the (R)-PLA matrix equal to 116,700 Da. The presence of nanotube-filler affected the alignment of polymer fibrils in the composite. The elaborated approach may be implemented to a larger scale fabrication of biodegradable composites for medicinal applications or other functional materials where an enhanced matrix-filler interaction is required. (C) 2012 Elsevier B.V. All rights reserved.