端羧基超支化聚酯高吸收铬鞣助剂研究

Study on the Carboxyl Terminated Hyperbranched Polyester as an Auxiliary for High Absorption Chrome

在铬鞣中使用质均分子量1909,支化度为0.72的水性端羧基超支化聚酯HBP-4作为高吸收铬鞣助剂,探讨其对铬鞣剂耐碱稳定性的影响,考查其添加时间节点、添加量对铬鞣效果的影响,及其在自碱化铬鞣中的应用。结果表明,HBP-4在提碱开始时加入,用量为皮重的1.5%时,铬吸收率比对照组增加22.3%,蓝皮收缩温度提高5℃,成革抗张强度最多可提高86.2%。鞣后蓝皮断面扫描电镜照片证实了HBP-4可提高胶原纤维的交联密度。HBP-4用在自碱化铬鞣中也可提高铬吸收率和成革品质。

A water-soluble carboxyl terminated hyperbranched polyester HBP-4(Mw=1909,DB(degree of branching)=0.72)was used as high absorption chrome tanning auxiliary.Firstly,the effect of HBP-4 on the alkali resistance of chrome tanning agent was determined.Then the optimum application process of HBP-4 was investigated by changing its dosage and adding time.The results showed that when the HBP-4 was added at the beginning of basifying treatment and the dosage of HBP-4 was 1.5%of the leather weight,the chromium absorption rate was increased by 22.3%,the shrinkage temperature of wet-blue leather was increased by 5℃,and the tensile strength of leather was increased by 86.2%.The SEM photos for the fracture surface of tanned wet-blue leather confirmed that HBP-4 could increase the crosslinking density of collagen fibers.Moreover,HBP-4 can also improve the chrome absorption,thermal stability and mechanical property of leather in the self-alkalifying chrome tanning.