Synthesis Of Aminosulfonic-Based Superplasticizer And Its Utilization On Highly-Fluidized Concrete

Superplasticizer is a kind of concrete additive which can improve workability and reduceevidently water of concrete, and it is one of the important products of new building materialsindustry. In this paper the history of inventing, the status of producing and application ofsuperplasticizers are described in detail, and the characteristics of the main typesuperplasticizers as well are summarized. The action mechanism of superplasticizer is alsodiscussed. On the basis of carefully analyzing and summarizing the factors influencingaminosulfonic-based superplasticizer properties such as molar ratio of reactors, the reactiontemperature and time, the pH value of reaction solution and the drippy speed of formaldehyde,the optimum parameters of synthesizing technology have been determined. By theco-polycondensation of p-aminobenzene sulfonic acid, phenol and formaldehyde, ASP wassynthesized successfully in laboratory. According to standards of GB/T8077-2000, theproperties such as the main uniformity, fluidity of cement paste, compatibility with differentcements, water reducing rate of mortar have been tested. Some properties of naphthalenesulfonate superplasticizer are also tested and compared with ASP. The results show that, theASP is a kind of low-alkali water reducing agent, with high dispersivity, less or none flow lossof cement paste, accommodated well with 3 kinds of cement in Nanning made by rotary kiln.The water reducing rate of is 25.9% with dosage of 1.0% (weight of cement). The modifiedASP was made by using some admixtures. The water-reducing rate of the modified ASP was greatly improved and the bleeding ratio of paste was decreased at low dosage. It is asignificant attempt in modifying the performance of aminosulfonic-based superplasticizer.The ASP was used to make highly fluidized concrete which property was studied as well.When the water-binder ratio of concrete is 0.35, the dosage of ASP is 0.39%, the slump isover 25cm, the spread diameter is over 55cm. Concrete with ASP shows well fluidity andself-compacting, and the 28-days compressive strength of concrete is over 50MPa. It satisfiesthe construction well in high temperature weather of summer in Guangxi ZhuangAutonomous region.