改性聚天冬氨酸的热缩共聚合成

Thermal polycondensation synthesis of modified polyaspartic acid

以天冬氨酸(Asp)、谷氨酸(Glu)为原料,热缩共聚得到改性聚天冬氨酸(即Asp/Glu共聚物,PAG)。考察了反应条件对共聚物产率和重均分子质量的影响,并研究了重均分子质量与其阻垢性能的关系。结果表明:以Na2SO4为催化剂,聚合温度为180℃,n(Glu)∶n(Asp+Glu)=0.1,n(催化剂)∶n(Asp+Glu)=0.030,反应100 min,共聚物的产率达到96.2%,相对分子质量约为2 200,对硫酸钙的阻垢效果最佳;在同样的反应温度、原料配比和催化剂用量的条件下,反应120 min,所得产物的相对分子质量约为3 000,产率达99.4%,对碳酸钙具有最佳阻垢效果。

Modified polyaspartic acid （copolymer between aspartic acid and glutamic acid, PAG） was synthesized with aspartic acid and glutamic acid as raw materials, The influence of reaction conditions on the product conversion rate and the weight average molecular weight was investigated. And the relationship between the weight average molecular weight of the copolymer and its scale inhibiting was analyzed. The results showed that the yield and weight average molecular weight of the copolymer were 96,8% and 2200 respectively when the reacting substance reacted at 180℃ for 100min with Na2SO4 as the catalyst,and with 0.1 of n（Glu） ： n（Asp ＋ Glu） and 0.035 of n（catalyst） ： n（Asp ＋ Glu） .The copolymer made under the above conditions had good inhibiting on CaSO4, Under the same conditions of reaction te,nperature, n （Glu） ： n （ Asp ＋ Glu） and n （catalyst）： n （Asp ＋ Glu） the yield and weight average molecular weight of the copolymer is respectively 99.4% and 3 000 after 120 min of reaction. And the copolymer had optimal inhibiting on CaCO3 ,