AbstractThe reaction of cotton cellulose with d,l isomers of butadiene diepoxide (BDO) in the presence of base catalysis has been investigated as a continuation of work previously reported on the reaction between cotton cellulose and the meso isomer (BDE). The BDO has been found to react similarly out of CCl4 solutions with fabrics pretreated with dilute solutions of base. However, unlike the meso isomer, which is less soluble in concentrated base, the BDO has been found to increase dry as well as wet crease resistance of cotton pretreated with aqueous solutions as concentrated at 23% NaOH. Increased wet crease resistance was imparted to cotton at low add‐ons of BDO to fabric pretreated with all concentrations of base. Increased dry crease resistance was imparted at low add‐ons of BDO to only those fabrics pretreated with dilute solutions of NaOH. For those fabrics pretreated with 10% or 15% NaOH, higher add‐ons of BDO were required to impart high dry as well as high wet crease resistance. Speed of the reaction was increased with increase of base concentration or by removal of water from fabrics pretreated with dilute base. With the latter, rate of increase of dry crease resistance also increased. Optical microscopical examinations of fibers and electron micrographs of ultrathin cross sections of these fibers after immersion in cuene gave evidence of degree of crosslinking of the cellulose. Evidence from these microscopical observations has been correlated with textile properties of fabrics. Intersting changes in fabric properties of BDO treated cotton with heat have been investigated. Optimum fabric properties have been obtained by reducing the amount of water in cotton after pretreatments with aqueous base and thus reducing the degree of polymerization of BDO. Data are also given to show influence of hydration of cation of strong base on degree of polymerization of BDO.