酰化单宁的制备及其鞣制性能  

Preparation and tanning properties of acylated tannin

作　　者：郭林新 强涛涛 马养民 任龙芳 GUO Linxin;QIANG Taotao;MA Yangmin;REN Longfang(College of Bioresources Chemical and Materials Engineering,Shaanxi University of Science&Technology,Xi'an 710021,Shaanxi,China;College of Chemistry and Chemical Engineering,Ankang University,Ankang 725000,Shaanxi,China;Key Laboratory of Chemical Additives for China National Light Industry,Xi'an 710021,Shaanxi,China)

机构地区：[1]陕西科技大学轻工科学与工程学院,陕西西安710021 [2]安康学院化学化工学院,陕西安康725000 [3]中国轻工业轻化工助剂重点实验室,陕西西安710021

出　　处：《精细化工》2021年第12期2546-2551,2557,共7页Fine Chemicals

基　　金：陕西省教育厅重点科学研究计划(协同创新中心项目)(20JY003);陕西高校青年创新团队。

摘　　要：以单宁为原料,制得酰化单宁。优化反应条件,并以酰化单宁为鞣剂进行皮革鞣制,测定皮革的性能并推断鞣制机理。结果表明,将1 g单宁溶于6 g三氟乙酸中,添加1.5 g乌洛托品,在100℃下回流反应1.5 h,制备得到醛基含量为2.33 mmol/g的酰化单宁。以酰化单宁为鞣剂,鞣制皮革的收缩温度可达(85.3±2.5)℃,撕裂强度为(47.7±1.3)N/mm,抗张强度为(10.2±1.1)MPa,断裂伸长率为97.9%±2.0%,优于未改性单宁鞣制的皮革。此外,鞣制的皮革还具有较强的抗紫外性能。酰化单宁保留了其原有的活性基团,在鞣制过程中与皮革胶原纤维分子形成氢键交联作用,引入的醛基可以和胶原纤维分子中的氨基发生反应形成稳定的化学键。在两种作用力的共同影响下,使得皮革的性能得到显著提高。Acylated tannin was prepared from tannin, the reaction conditions were optimized and the acylated tannin was used as tanning agent for leather tanning. The properties of the tanned leather were measured and the tanning mechanism was inferred. The results showed that by dissolving 1 g of tannin in 6 g of trifluoroacetic acid, adding 1.5 g of hexamethylenetetramine, and reflux reaction for 1.5 h at 100 ℃, the acylated tannin with aldehyde group content of 2.33 mmol/g was prepared. The shrinkage temperature of leather tanned with acylated tannin was(85.3±2.5) ℃, the tear strength was(47.7±1.3) N/mm, the tensile strength was(10.2±1.1) MPa, and the elongation at break was 97.9%±2.0%, which were better than those of unmodified tannin tanned leather. In addition, the tanned leather also had strong anti-ultraviolet capability.Acylated tannin retained their original active groups, which could form hydrogen bond cross-linking with leather collagen fiber molecules during the tanning process. The introduced aldehyde groups could react with the amino groups in the collagen fiber molecules to form stable chemical bonds. The combined influence of the two forces made the properties of tanned leather significantly improved.

关 键 词：单宁 酰化改性 抗紫外性能 鞣制机理 皮革化学品 

分 类 号：TS529.2[轻工技术与工程—皮革化学与工程]