Utilization of Partially Methylolated Poly acrylamide Guar Gum in Pigment Printing

Polyacrylamid-guar gum composite has been prepared via graft copolymerization of acrylamide onto guar gum using the KBrO₃/ thiourea redox system. The amide groups (40%) in the composite are converted to reactive groups through methylolation with formaldehyde, with a view to obtaining reactive composite. The composite and the reactive composite were used as pastes for printing cotton fabrics with pigment dyes. The prints were assessed for color strength (K/S) and overall fastness properties.

Printing was carried out under different conditions, including the amount of composite used as a substitute for kerosene emulsion, the amount of binder incorporated into the printing paste and the types of catalysts. The printed samples were evaluated by monitoring the color strength (K/S) and fastness properties such as washing, rubbing and light. Based on the results obtained, it is concluded that a partial substitution ratio of 20/75 (composite/kerosene emulsion), 8gm binder/100gm printing paste and 1% of catalyst (NH4Cl, DAP, Citric acid or [NH4]2SO4) represent the proper formulation for gaining good dye fixation and excellent fastness properties. The results indicate that the reactive composite prepared is the most suitable thickener for printing cellulosic fabrics with pigment dyes.