Leather and Shoe Research Association of New Zealand, P.O. Box 8094, Palmerston North, 4472, New Zealand.
Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, UK.
Int J Biol Macromol. 2019 Apr 1;126:123-129. doi: 10.1016/j.ijbiomac.2018.12.187. Epub 2018 Dec 22.
The inefficiency of the chromium (III)-collagen cross-linking reaction during conventional leather processing results in severe environmental pollution from the waste chromium in the effluent. A mechanistic study using synchrotron-based small-angle X-ray scattering (SAXS) and differential scanning calorimetry (DSC) on ThruBlu tanned leather, revealed the effect of chromium sulphate and its pre-treatments on collagen structure and stability. By pre-treating with complexing agents such as sodium formate and disodium phthalate, as well as nanoclay (sodium montmorillonite), the uniformity through bovine hide collagen matrix were improved significantly. These pre-treatments effectively reduce the reactivity of chromium during its cross-linking reaction with collagen while retaining its bound water. However, collagen pre-treated with a covalent cross-linker (glutaraldehyde) results in a decrease in both chromium-collagen cross-linking and bound water while improving uniformity. These molecular-level insights can be developed into metrics to guide us towards a more sustainable future for the leather industry.
传统皮革加工过程中铬(III)-胶原交联反应的效率低下，导致废水中的铬对环境造成严重污染。利用基于同步加速器的小角 X 射线散射（SAXS）和差示扫描量热法（DSC）对 ThruBlu 鞣制皮革进行的一项机理研究，揭示了硫酸铬及其预处理对胶原结构和稳定性的影响。通过用甲酸钠和邻苯二甲酸钠等络合剂以及纳米粘土（钠蒙脱石）预处理，可以显著提高牛真皮胶原基质的均匀性。这些预处理方法在保持结合水的同时，有效降低了铬与胶原交联反应的活性。然而，用共价交联剂（戊二醛）预处理胶原会导致铬-胶原交联和结合水减少，同时提高均匀性。这些分子水平的见解可以发展成为指导我们皮革工业走向更可持续未来的指标。
