一种高性能聚羧酸减水剂的合成研究

Synthesis of Polycarboxylate Superplasticizer

以聚乙二醇单甲醚1200(MPEG1200)与丙烯酸(AA)为原料,在无溶剂条件下进行酯化法,成功制备了丙烯酸聚乙二醇单甲醚1200酯(AA-MPEG1200)大单体。并以所合成的大单体与甲基丙烯酸(MAA)、甲基丙烯磺酸钠(SMAS)、2-丙烯酰胺基-2-甲基丙磺酸(AMPS)等不饱和单体在过硫酸铵(APS)引发下共聚,合成聚羧酸减水剂。经正交实验优选出最佳合成工艺条件如下:即MAA/AA∶MPEG-AA为4∶1,AMPS∶MPEG-AA为0.4∶1,SAS∶MPEG-AA=0.6∶1,APS用量为单体总质量的5%;反应温度为80℃、反应时间为8 h。所合成的聚羧酸减水剂具有良好的分散性和保塑性。

Acrylic acid methoxypolyethylene glycol 1200 ester （AA-MPEG1200） as was successfully synthesized by solvent-free reaction of methoxypolyethylene glycol 1200 （MPEG1200） and acrylic acid （AA）. The synthesized intermediate macromonomer was mixed with methylacrylic acid （MAA）, sodium methallyl sulfonate （SMAS）, 2-acrylamide-2-methyl propane sulfonic acid （AMPS） to synthesis polycarboxylate superplasticizer in the presence of initiator ammonium persulfate （APS）. The optimum synthetic conditions for the macromonomer were obtained by orthogonal experiments as follows： the molar ratio of MAA/AA to MPEG-AA is 4 ： 1, the molar ratio of AMPS to MPEG-AA is 0.4 ： 1, the molar ratio of SAS to MPEG-AA is 0.6 ; 1, the amount of APS is the 5 % according to the mass of macromonomer. The optimum reaction temperature and time is 80 ℃ and 8 h. In addition, the polycarboxylate water reducer synthesized by this macromonomer displays good dispersability and fluidity keeping ability.