Grafting Polymerization On Cellulose Based Textiles: A 13C Solid State NMR Chracterization

Grafting of methyl methacrylate and ethyl acrylate onto cellulose chains of textiles with oxidized sites has been carried out. To this aim, carboxyl and carbonyl groups have been introduced by oxidation of the cellulose and used as photosensitive agents, allowing the formation of radical sites. The copolymerization has been started irradiating the substrate with ultraviolet light for a short time. With the grafting of acrylic monomers the mechanical strength and the thermal stability of cellulose based textiles may be improved, as well as the resistance to chemical and biological agents. The method has been successfully tested performing the grafting on a naturally aged cotton sample. It is worth to note that the grafting does not affect the aspect of the material. All samples have been characterized with 13C solid state NMR spectroscopy. A semi-quantitative evaluation of the grafting has been performed either studying the cross-polarization dynamic process, or by direct integration of resonances in 13C single pulse excitation spectra.