再生植物鞣剂的性能与应用

Properties and Application of Re-generated Vegetable Tanning Agent

为充分利用植鞣废液中的酚类物质,减少废液排放量,采用亚硫酸钠对植鞣废液进行磺化;然后用甲醛进行交联制备再生植物鞣剂;再从组成、结合能力、渗透能力和鞣制性能等方面对比了再生植物鞣剂与杨梅栲胶的异同,并将再生植物鞣剂与杨梅栲胶共同用于植鞣过程,同时对鞣制所得植鞣革的性能进行表征。实验结果表明,再生植物鞣剂中单宁含量低、非单宁含量高,与皮胶原蛋白的结合能力和结合稳定性较弱,粘度较高且渗透性速度较慢,但是在单宁含量为8 g/L时可使皮粉收缩温度达81.2℃。再生植物鞣剂与杨梅栲胶共同用于植鞣过程,所得植鞣革撕裂强度更好、收缩温度更高,抗张强度、断裂伸长率、粒面和横切面形貌与常规植鞣革无显著差异。本研究可为植鞣废液的循环利用以及植鞣清洁化过程提供参考。

For fully utilizing the phenolic substances in vegetable tanning effluent and reducing effluent discharge during vegetable tanning process,the effluent was sulfonated with sodium sulfite at first,and then formaldehyde was used to crosslink to prepare re-generated vegetable tanning agent(RVTA).Then the similarities and differences between bayberry extract and RVTA were compared in terms of component,combination ability,penetration and tanning properties.RVTA was used in tanning process with bayberry extract,and the performances of tanned leather were also tested.The results showed that there was more non-tannin composition but less tannin composition in RVTA and it had weak combination ability and stability with collagen together with slightly poor permeability.However,shrinkage temperature of hide powder tanned by RVTA could reach 81.2 ℃ when tannin content was 8 g/L.By using RVTA together with bayberry extract in vegetable tanning process,the tear strength and shrinkage temperature of the leather was better,and the tensile strength,elongation,grain and cross-section morphology were comparable with leather tanned by bayberry extract.This work would provide a reference for vegetable tanning effluent recycling and cleaning process of vegetable tanning.