Technological evaluation of methacrylic acid/fenugreek gum grafted products as thickener in textile printing
The graft copolymerisation of methacrylic acid onto fenugreek gum has been performed using potassium persulphate as initiator. The rheological properties of the grafted product and its utilization as a thickening agent in printing cotton fabrics with reactive dyes were thoroughly investigated. It was found that polymethacrylic acid/fenugreek gum grafted products are characterised by non-Newtonian pseudoplastic behaviour. The apparent viscosity at a constant rate of shear depends on the amount of the monomer used. Furthermore, the results obtained indicate that polymethacrylic acid/fenugreek gum grafted products can be used safely, either alone or in a mixture with sodium alginate, to give printed goods characterized by soft handling and excellent colour fastness properties. Infra-red spectra of fenugreek gum before and after grafting with methacrylic acid indicate some physicochemical changes in the structure.