Microwave-assisted Synthesis of Modified Polyaspartic Acid in Solvent  

作　　者：张玉玲 黄君礼 程志辉 杨士林 

机构地区：[1]School of Municlpal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China

出　　处：《Chinese Journal of Chemical Engineering》2007年第3期458-462,共5页中国化学工程学报（英文版）

基　　金：Supported by Harbin Key Technologies R&D Program(No.2003AA4CS123).

摘　　要：Polyaspartic acid(PASP)is suitable for the inhibition of scale deposition from water.To enhance its in- hibition efficiency,PASP was modified by reacting aspartic acid(Asp)with glutamic acid(Glu)to provide Asp-Glu copolymer under microwave irradiation.The influence of reaction parameters on conversion,molecular weight and inhibition of CaCO3 precipitation was investigated Infra-red.(IR), 1H nuclear magnetic resonance( 1H NMR)and 13C nuclear magnetic resonance( 13C NMR)spectroscopies were used to characterize the copolymer.The results show that copolymerization of aspartic acid and glutamic acid is catalyzed by a small amount of phosphorous acid (H3PO4)in solvent,the product conversion is 98.05%under the following conditions:the molar ratio of glutamic acid to reactant[Glu/(Asp+Glu)]is 0.3 and that of catalyst(Cat)to reactant[Cat/(Glu+Asp)]is 0.05(0.65ml H3PO4),the volume of solvent dimethylformamide is 16ml,the microwave power used is 720W and the reaction for 3 min.The weight average molecular weight of copolymer synthesized under these conditions is 2709 and the inhi- bition rate for CaCO3 is 97.75%.Polyaspartic acid（PASP）is suitable for the inhibition of scale deposition from water.To enhance its inhibition efficiency,PASP was modified by reacting aspartic acid（Asp）with glutamic acid（Glu）to provide Asp-Glu copolymer under microwave irradiation.The influence of reaction parameters on conversion,molecular weight and inhibition of CaCO3 precipitation was investigated Infra-red.（IR）, 1H nuclear magnetic resonance（ 1H NMR）and 13C nuclear magnetic resonance（ 13C NMR）spectroscopies were used to characterize the copolymer.The results show that copolymerization of aspartic acid and glutamic acid is catalyzed by a small amount of phosphorous acid （H3PO4）in solvent,the product conversion is 98.05%under the following conditions：the molar ratio of glutamic acid to reactant[Glu/（Asp＋Glu）]is 0.3 and that of catalyst（Cat）to reactant[Cat/（Glu＋Asp）]is 0.05（0.65ml H3PO4）,the volume of solvent dimethylformamide is 16ml,the microwave power used is 720W and the reaction for 3 min.The weight average molecular weight of copolymer synthesized under these conditions is 2709 and the inhibition rate for CaCO3 is 97.75%.

关 键 词：microwave irradiation aspartic acid glutamic acid COPOLYMER conversion ratio scale inhibition 

分 类 号：O632.5[理学—高分子化学]