Reactions of halogenated 1,2-epoxypropanes and diethylaminoethyl cotton^†

Diethylaminoethyl (DEAE)-cotton has been reacted with epichlorohydrin (1,2-epoxy-3-chloropropane) neat, in alcoholic solvents, and in aprotic solvents at temperatures ranging from 25 to 95°C. Fabric properties and electron micrographs of fibers removed from these chemically treated DEAE cottons have been compared with those obtained when DEAE-cottons were treated under similar conditions with other halogenated 1,2-epoxypropanes, and with 1,2-epoxy-4,4,4-trichlorobutane. For comparative purposes, epichlorohydrin was reacted with an aminized cotton containing primary amine groups, with cotton containing quarternary ammonium groups, and with DEAE-cottons in which the tertiary amine groups had been quaternized. For reaction at 95°C with net epichlorohydrin, greatest increase in conditioned wrinkle recovery was observed with DEAE-cottons. Only with DEAE-cottons were the add-ons and recovery angles imparted by epichlorohydrin affected by the anion associated with the amine groups. None of the halogenated 1,2-epoxypropanes reacted with unmodified cotton in the absence of a basic catalyst. Those that reacted with unmodified cotton in the presence of an external base catalyst did not improve conditioned recovery angles. The mono-, di-, and trichloro-1,2-epoxypropanes all increased the conditioned and wet wrinkle recovery of DEAE-cotton when reacted neat at 95°C. The type of oxirane ring opening of epoxypropanes was shown to be influenced by the degree of chlorination of the carbon alpha to the ring. Both primary amine groups and quaternary amine groups catalyzed the epichlorohydrin–cellulose reaction. Dilution of epichlorohydrin with alcohols or decreasing reaction temperature lowered add-ons and improvements in wrinkle recovery properties. Use of aprotic solvents for the DEAE-cotton-epichlorohydrin reaction gave finished cotton fabrics having only high wet wrinkle recovery properties.