Finishing of cotton by methacrylic acid in presence of NaH2PO4 and K2S2O8 as catalysts under thermal treatment

Abstract Cotton fabric was modified using methacrylic acid (MAA) as the finishing agent in the presence of NaH2PO4 and K2S2O8 catalysts separately or in selected combinations, employing a pad–dry–cure technique. Treatment with 8% MAA at 30°C and at pH 6 produced optimum effects: a batching time of 45–60 min at 30°C followed by drying of the batched fabric at 95°C for 5 min and curing of the dried fabric at 140°C for 5 min produced most balanced improvements in the properties such as wrinkle recovery, abrasion resistance, extensibility and moisture regain with retention of more than 75% of the original strength. NaH2PO4 catalyst allowed esterification of MAA with the cellulosic constituent of the cotton, and K2S2O8 catalyst allowed radical polymerization of free MAA or cotton-bound MAA moieties; the said process ultimately led to some degree of cross-linking of the chain polymers of cotton.