AA-SAS共聚物混凝土抗泥剂的制备及性能

Preparation and Properties of AA-SAS Copolymer Anti-clay Agent for Concrete

摘要:

以丙烯酸（AA）和烯丙基磺酸钠（SAS）为原料合成一种共聚物抗泥剂AA-SAS，以改善泥土对混凝土性能造成的不利影响。采用IR、GPC、TG和XRD对共聚物进行了结构表征，考察了共聚物AA-SAS对含不同泥土的水泥净浆及混凝土工作性能的影响。结果表明，共聚物AA-SAS相对聚羧酸减水剂相对分子质量更低，扩散自由度更大，可以优先被混凝土中泥土吸附，从而减少泥土对减水剂的吸附，其对膨润土、高岭土、云母和渭河土均具有较好的抗泥作用。在高含泥量混凝土中添加共聚物AA-SAS后，混凝土工作性能明显得到改善，当共聚物AA-SAS折固掺量为混凝土胶凝材料质量的0.11%时，混凝土0.5h坍落度和扩展度分别提高了15和90mm，1h坍落度和扩展度分别提高了20和100mm。与作者前期合成的聚合物（AA-AM）混凝土抑泥剂相比，共聚物AA-SAS的抗泥效果更佳。

Abstract:

An anti-clay agent AA-SAS was synthesized by acrylic acid (AA) and sodium allylsulfonate(SAS) to improve the adverse effects of the clay for concrete. The copolymer was analyzed by IR, GPC, TG and XRD. The effect of the copolymer on the workability of cement paste and concrete with different clay was investigated. The results show that the molecular weight of AA-SAS is smaller and the diffusion rate of which is faster than polycarboxylate superplasticizer. The copolymer can be adsorbed preferentially by the clay in the concrete, thus reducing soil adsorbing polycarboxylate superplasticizer. The copolymer has a good anti effect on bentonite, kaolinite, mica and Weihe clay. The workability of concrete is improved obviously while adding the copolymer. When the solid content of AA-SAS was 0.11% of the cementing material, the 0.5 h concrete slump and fluidity is improved by 15 and 90 mm, and the 1 h concrete slump and fluidity is improved by 20 and 100 mm. In comparison with polymer（AA-AM）synthesized previously, the copolymer AA-SAS shows better property on resisting clay.