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Superplasticizer was in the 1990s the emergence of a new type of superplasticizer, with a low dosage of high dispersion, slump loss, high early strength cement and good adaptability, therefore, superplasticizer research are increasingly favored by society and become the focus of research at home and abroad. However, there still exist molecular structure design is unreasonable, synthetic process is also lack of systematic research, need to be further optimized, and on the synthesis mechanism and other aspects of the mechanism of the research work carried out by small, need to be further explored. The main subject for the above has done some work. This issue through molecular design, selection of acrylic acid, polyethylene glycol, sodium methacrylate as raw materials, and by means of orthogonal experiment and single factor test to identify the impact SUPERPLASTICIZERS significant factor is synthesized poly acrylic superplasticizer optimum process parameters. Accordance with the relevant standards and requirements admixtures, the subject of polyacrylic acid superplasticizer on homemade conducted a comprehensive evaluation of the performance, and with naphthalene superplasticizer and a foreign superplasticizer were compared. The results show that self-polyacrylic acid superplasticizer paste fluidity, slump loss, setting properties, water reduction and compressive strength are superior to currently naphthalene superplasticizer, but also with ordinary portland cement has a good adaptability to achieve concrete admixtures qualified requirements. But with a foreign presence superplasticizer also have a certain gap, the synthesis process needs to be further improved. By UV-visible spectroscopy, infrared spectroscopy, gel permeation chromatography (GPC), high performance liquid chromatography method for analysis of its composition and structure, are discussed in the polymer having a functional group of the types and number average molecular weight and its distribution and composition and the relationship between performance and further analysis of the polyacrylic acid superplasticizer mechanism of action. Its main mechanism for the reduction of water and cement superplasticizer adsorption between a particle dispersion, ie a cement superplasticizer a water system superplasticizer adsorbed on the surface of cement particles to form a double layer, resulting in electrostatic repulsion role in the adsorption process, the main chain length side chains in the system can be fully extended and play space steric effect, it superplasticizer cement particles can produce stronger dispersion and dispersion stabilizing role.
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