Admicellar Polymerization and Mixing in a Laboratory Dyeing Unit-A Variant of Rocking Reactors

Abstract

Mass transfer in a laboratory dyeing machine, consisting of cylindrical canisters mounted on a carousel with a horizontal axis, has been examined to adapt the unit for modification of cotton by admicellar polymerization. Canisters located at the periphery of the carousel are canted relative to the axis of rotation so that fluid in the canister moves front-to-back and back-to-front over the course of one revolution in a fashion similar to a rocking reactor. Dissolution of benzoic acid in water at 30 °C has been used to determine mass transfer coefficients β in the dyeing system as a function of rotational rate and fill volume. Mixing in the dyeing system improved with canister fill fraction to an optimum of 0.9, while rotation rate had little effect over the available range. Findings for β as well as predictions for β obtained from estimates of specific mixing power are compared to values from the literature for a rocking reactor. The process of admicellar polymerization on cotton was subsequently examined in the laboratory dyeing machine. Cotton with a water repellent coating prepared in the unit was evaluated using various techniques. Conditions favorable to mass transfer in the model experiments were consistent with those providing optimal performance of the water-repellent coating applied by admicellar polymerization.

Admicellar Polymerization and Its Application in Textiles

“…(Table XIII is a compilation of the polymerization process parameters of all the applications of ADPM cited in this review.) There has been a study to perform ADPM in laboratory dyeing units, 122 and its industrial developments for inorganic substrates have been reported. 123 Substantial literature [124][125][126][127][128][129][130][131][132][133][134] is also available on ADPM, which highlights its potential in commercial application.…”