木质素栲胶的制备、表征及复鞣的作用

采用氢气还原降解木质素的方法制备了木质素栲胶,用Folin-Ciocalteu试剂法对木质素栲胶中酚羟基含量的变化进行了测定,并利用紫外吸收光谱和红外吸收光谱对其化学结构进行了分析。用木质素栲胶对铬鞣猪皮正面革进行复鞣实验,研究了不同用量木质素栲胶对成革感观和物理性能的影响。结果表明,降解后木质素栲胶中酚羟基的质量摩尔浓度增加了30.12%;当木质素栲胶的加入量为2%时,成革的弹性和柔软性好,丰满度良好,粒面紧实,收缩温度为94.8℃,抗张强度为14.5N/mm2,撕裂强度为19.3N/mm,复鞣效果最佳。木质素栲胶的复鞣性能达到了植物复鞣剂的水平。

Preparation, characterization and retanning function of lignin extract

Lignin extract was prepared by degradation of lignin with hydrogen.The content of phenolic hydroxyl of lignin extract was determined by Folin-Ciocalteu reagent method and the chemical structure was analyzed by means of UV and FT-IR.Lignin extract was used in chrome-tanned pigskin grain leather retanning test,the effects of different amount of lignin extract on leather appearances and physical properties were studied.The results showed that the content of phenolic hydroxyl of lignin extract was increased by 30.12%.The retanning effect was best when the amount of lignin extract was 2%,the leather was elastic,soft and full,the grain face was tight,the shrink temperature was 94.8 ℃,the tensile strength was 14.5 N/mm2 and the tear strength was 19.3 N/mm.The retanning performances of lignin extract are as well as vegetable retannage.