不同磷酸酯单体的EPEG型聚羧酸减水剂的制备及抗泥性能

Preparation and mud resistance of EPEG polycarboxylate superplasticizer with different phosphate monomers

摘要:

以乙二醇单乙烯基醚（EPEG）为大单体，丙烯酸（AA）为小单体，2-羟乙基甲基丙烯磷酸酯（HEMAP）或封端酰胺磷酸酯（CAP）为功能单体，采用水溶液自由基共聚法合成了两种EPEG型抗泥型聚羧酸减水剂PCE-EP1和PCE-EP2。采用FTIR、1HNMR对减水剂结构进行表征，通过水泥净浆流动度测试了合成的减水剂对水泥的分散性能以及抗泥性能，并结合XRD，XPS探究了减水剂与水泥、蒙脱土之间的作用机理。结果表明：当减水剂折固掺量为0.2%，蒙脱土掺量为2%时，掺PCE-EP1和PCE-EP2有一定的抗泥性。XRD表明说明减水剂PCE-EP1、PCE-EP1对蒙脱土没有进行插层吸附，从而提高了该减水剂对泥土的分散能力。

关键词:EPEG;聚羧酸减水剂;蒙脱土;分散性;抗泥性

Abstract:

With ethylene glycol monovinyl ether (EPEG) as the major monomer, acrylic acid (AA) as the minor monomer, and 2- hydroxyethyl methacrylate (HEMAP) or blocked amide phosphate (CAP) as the functional monomer, two EPEG mud-resistant polycarboxylate superplasticizers PCE-EP1 and PCE-EP2 were synthesized by free radical copolymer-ization in aqueous solution. The structure of superplasticizer was characterized by FTIR and 1HNMR. The dispersion and anti-mud performance of the synthesized superplasticizer to cement were tested by the fluidity of cement paste. Combined with XRD and XPS, the interaction mechanism between superplasticizer and cement and montmorillonite was explored. The results show that when the dosage of superplasticizer is 0.2% and the dosage of montmorillonite is 2%, PCE-EP1 and PCE-EP2 have certain mud resistance. XRD shows that the water reducing agents PCE-EP1 and PCE-EP1 have no intercalation adsorption on montmorillonite, thus improving the dispersing ability of the water reducing agent to soil.

Key words:EPEG; polycarboxylate superplasticizer; montmorillonite; dispersion; mud resistance