The Chemical Modification of the Tara Micropowder and Its Application in Tanning

摘要

Tara is a leguminosae whose pod is abundant in about 60% tannins and the others are non-tannin, cellulose, semicellulose and polysaccharides etc. Tara extract is widely used in tanning and preparation of gallic esters. In this paper, Tara bean pod was comminuted ultrafine to micropowder at the first, and then chemically modified by oxidative degradation with H_2O_2. The modified product can be used directly in tanning or retanning without extracting of Tara. Thereby, the utilization ratio of vegetable tannin from Tara pod is increased. The modified micropowder has good dispersing and penetrating capability and water solubility. It is shown that resultant leather has lighter colour and better fillness than Tara extracts, and has more full and tight handles.