Abstract:

A new bicyclooxazolane retanning agent (Retanal X-1) and glutaraldehyde were used to retanning for the cattle blue wet leather, respectively.At the same time the synthetic tanning agent and wattle extract retanning agent also have been used in order to compare the application results. The above processes also have been carried out with sheep blue wet leather.After retanning,the total chemical oxygen demand (COD), total chromium content (TCr), total nitrogen content (TKN) of waste water were determined, and the physical and mechanical properties of the obtained leather were measured.The results showed that the retanned cattle leather with Retanal X-1 displayed softer and higher physical and mechanical properties than leather treated with the glutaraldehyde agent and the former demonstrated higher chrome adsorption(39.7%) after synthetic tanning and wattle extract were added.The retanned sheep leather with Relugan RE acrylic resin retanning agent revealed better physical and mechanical resistance than leather treated with the other two acrylic resin retanning agents, the results also showed that the retanned sheep leather with Relugan RE,owned the highest chrome adsorption(6.45%),among the three acrylic resin retanning agents.In summary, the experimental results indicated that Retanal X-1 could increase the absorption of chromium and improve the physical and mechanical properties of the leather.

Key words: oxazolidine, application, retanning, chromium absorption