乙醛酸/2-氨基-1,4-苯二磺酸Schiff碱的制备与助浸酸性能

Preparation of Schiff Base of Glyoxylic Acid and 2-Amino-1,4-Benzenedisulfonic Acid and its Application in Pickling

摘要:

以乙醛酸和2-氨基-1,4-苯二磺酸为主要原料，制备了一种富含磺酸基和羧基的Schiff碱，将得到的Schiff碱作为浸酸助剂应用于制革浸酸过程中，并对酸皮膨胀度、蓝皮收缩温度、废液铬含量等指标进行了测试。结果表明：质量分数2％（以灰皮质量为基准，下同）的浸酸助剂应用于无盐浸酸，皮块膨胀度为4％左右，在此基础上复配质量分数1％的NaCl，皮块不膨胀。将质量分数4.5％的铬粉应用于少盐浸酸铬鞣，蓝湿革收缩温度（Ts）可以达到105.5℃。与传统浸酸铬鞣相比，废液中Cr2O3的质量浓度从3.305g/L下降1.546g/L，Cl-的浓度从374.2mmol/L下降至59.6mmol/L。ESEM结果表明：少盐浸酸铬鞣蓝湿革纤维分散均匀，粒面平整，毛孔清晰。EDS结果表明：铬元素在皮块纵切面方向分布均匀，抗张强度、断裂伸长率及撕裂强度较传统浸酸铬鞣分别提高至32.8MPa、56.8％和80.2N/mm。

Abstract:

A Schiff base rich in sulfonic acid group and carboxyl group was prepared by glyoxalic acid and 2-Amino-1,4-benzenedisulfonic acid and was treated as pickling auxiliary used in pickling process，swelling rate of acidic pelts, shrinking temperature of wet-blue leather, the content of Cr2O3 and of spent tanned liquor has been determined. Result shows: 2％ pickling auxiliary（based on limed pelts weight, same below） was used in salt-free pickling, swelling degree of pelts pickled was about 4％, on this basis, 1％ sodium chloride was added into pickling liquor, swelling phenomenon of pelts pickled was avoided. 4.5％ chrome powder was applied to less-salt pickling chrome tanning, Ts of wet-blue leather could achieve to 105.5℃. Compared with traditional pickling chrome tanning process, the content of Cr2O3 and Cl- of spent tanned liquor significant were reduced from 3.305g/L和374.2mmol/L to 1.546g/L and 59.6mmol/L. Observation from ESEM showed that fiber uniformly dispersed, surface smooth, pores clear, and EDS showed chromium elements was uniformly distributed in cross section of pelts. Compared with traditional process, tensile strength, elongation at break and tear strength were up to 32.8MPa, 56.8％ and 80.2N/mm respectively.