Dyeing of Newly Synthesized Poly (Methacrylic Acid)-Carbamoylethylated Cotton Graft Copolymers

Unmodified cotton (substrate 1), carbamoylethylated cottons (CEC) having 0.21, 0.67 and 1.1% N (substrate II-IV) were graft copolymerized with methacrylic acid (MAA) at different initiator (PMPS) and monomer concentrations. This was done to tailor poly (MAA)-grafted carbamoylethylated cottons having different graft yields (expressed as meq-COOH/100 g sample). The resulted tailored cotton graft copolymers were dyed with two different dyes namely direct dye as well as basic dye (that has no or little affinity to cotton cellulose) to see their suitability towards dyeing. It was found from the data that; (a) the graft yield increases by increasing the initiator and monomer concentration within the range studied irrespective of the substrate used and follows the order: substrate IV>substrate III>substrate II>substrate I; (b) the introduction of carbamoylethylated groups (CONH2) in the molecular structure of cotton cellulose offered extra additional sites for graft copolymerization reaction, that enhance the susceptibility of cotton towards grafting; (c) the colour strength K/S of carbamoylethylated cottons dyed with direct dye decreases after copolymerization with poly (methacrylic acid) prior to dyeing; (d) the resulted poly (MAA)-carbamoylethylated cottons graft copolymers show higher affinity for basic dye and bring about what we called perceptible shade and (e) dyeing of unmodified cotton and poly (MAA)-cotton graft copolymer were done just for comparison.