AlCl₃-Et₃NHCl离子液体中聚天冬氨酸的合成

杨士林,刘春涛,曲滨鸿,黄君礼

1.哈尔滨工业大学市政环境工程学院;2.黑龙江大学化学化工与材料学院



摘要:

为改进传统L-天冬氨酸液相聚合方法,以L-天冬氨酸为原料,在AlCl3-Et3NHCl离子液体中液相聚合合成聚天冬氨酸(PASP).研究离子液体组成、反应条件对聚天冬氨酸重均分子量及其CaCO3阻垢效果的影响,分析产品的红外谱图特征.结果表明,在离子液体AlCl3-Et3NHCl中合成产品具有PASP结构特征;PASP聚合物重均分子量为1 000～5 000;聚合反应的最佳条件为:AlC13与盐酸三乙胺的摩尔比为2.2∶1、反应温度为220℃、天冬氨酸质量浓度为0.2 g/mL、反应时间为2.0 h,其合成产物重均分子量为4 750、对CaCO3阻垢率最佳可达93.8%,与传统液相聚合工艺相比阻垢率提高5%.离子液体可以用于L-天冬氨酸液相聚合.

关键词:  离子液体  聚天冬氨酸  合成  阻垢性能

DOI：10.11918/j.issn.0367-6234.2011.06.009

分类号:TQ085.4

基金项目:黑龙江省自然科学基金资助项目(E2007-25)



Synthesis of polyaspartic acid in AlCl₃-Et₃NHCl ionic liquids

YANG Shi-lin^1,2, LIU Chun-tao³, QU Bin-hong³, HUANG Jun-li¹

1.School of Municipal and Environmental Engineering,Harbin Institute of Technology,150090 Harbin,China;2.School of Chemistry and Materials Science,Heilongjiang Univercity,150080 Harbin,China);3.School of Chemistry and Materials Science,Heilongjiang Univercity,150080 Harbin,China)

Abstract:

To improve traditional L-aspartic acid polymerization in organic liquids,Polyaspartic acid(PASP) was synthesized in the medium of AlCl3-Et3NHCl ionic liquids by polymerization using L-aspartic acid as a raw material.The influence of composition of ionic liquids and reaction conditions on PASP weight average molecular weight and inhibiting effect on calcium carbonate were studied.The characteristics of the infrared spectrum of the product were analyzed.The results show that the obtained product in the medium of AlCl3-Et3NHCl ionic liquids is PASP,the molecular weight of PASP is between 1 000-5 000,and the optimal conditions of polymeric reaction are that the molar ratio of anhydrous aluminum chloride and triethylamine hydrochloride is 2.2∶1,reaction temperature is 220 ℃,concentration of L-aspartic is 0.2 g/mL and reaction time is 2.0 h.Under the above conditions,its molecular weight is 4 750,the scale inhibition rate to calcium carbonate reaches to 93.8% and it is increased by 5% compared with the traditional liquid-phase polymerization process.The PASP can be synthesized in ionic liquids.

Key words:  ionic liquids  polyaspartic acid  synthesis  scale inhibition performance