Effect of acid value on the esterification mechanism of maleinized soybean oil with cotton

Aqueous solutions of maleinized soybean oil (MSO) were evaluated as formaldehyde-free reagents for cellulosic textiles. The reactivity of cotton cellulose with MSO reagents (having acid values of 156 and 230 mg KOH/g) neutralized with aqueous ammonia, in excess of functional groups, was studied using diffuse reflectance infrared Fourier transform spectroscopy. The acid value of aqueous ammonia-neutralized MSO influenced the formation of protonated amide intermediates. Cyclic anhydride and protonated amide functional groups were identified as reaction intermediates, which resulted in carboxylic ester linkages between MSO and cellulose upon elevated temperature curing.