Modification of jute fibre by sulphonation for diverse textile use

Jute fibre is, by nature, hard and coarse. Treated with a sulphite of sodium in its neutral solution at about 165degreesC some of its properties were found to improve as lignin undergoes sulphonation reaction. Incrustation due to lignin is loosened, dislocated and partially removed as soluble lignin sulphonates come out in solution, but a major portion of them condenses to form solid lignin sulphonates remaining insoluble in the fibre and imparting new properties to fibres. Carbohydrate materials like hemicelluloses are also removed proportionately with the soluble lignin sulphonates. The rate of delignification as well as condensation of lignin sulphonates in the fibre was found to be dependent upon the degree of sulphonation of the fibre. It is seen that the sulpho-groups; increase rapidly at the beginning of the treatment. The ratios of acidic sulphur to total sulphur lie within the limit of about 0.75, which means that about 25% of the sulphur was non-acidic in the sulphonated jute fibre.