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Synthesis and the Effects of New Melamine Superplasticizer on the Properties of Concrete

DOI: 10.1155/2013/708063

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Abstract:

This work deals with the synthesis of new melamine superplasticizer (NMS) with high molecule weight and comparatively high processing thermostability by the reaction among melamine, formaldehyde, and sulfonated glucose. The surface activity and the structure of new melamine superplasticizer and their performance in concrete were evaluated. The effect of molecular weight of synthesized new melamine superplasticizer on the performance of the concrete was determined. The results showed that the new melamine superplasticizer has been proved to be more efficient as a superplasticizer used in concrete. 1. Introduction Superplasticizers (SPs) are recognized as important admixtures for their applications in modern concrete technology. Efforts have long been made by scientists and technologists to keep fresh concrete fluid to provide homogeneous transport of all particles in the building industry [1]. Traditional techniques which use the superplasticizers such as sulfonated melamine formaldehyde condensate (SMF) and sulfonated naphthalene formaldehyde condensate play a positive role in maintaining high fluiding concrete. The superplasticizers interact with the surface of cement particles and involve dispersion and decreasing of the natural tendency to coagulate in concrete. Polycarboxylates (PC) are recently commonly used as superplasticizers to disperse cement particles in concrete and mortar. However, it has been known that the dispersing force of PC for cement and its time variation are significantly affected by even slight differences in concrete components or mixing conditions. Such instability of the dispersing force is explained by the incompatibility between cement and PC [2–4]. Moreover, the side chain of the copolymer-type PC is composed of polyethylene oxide units. The methyl oxide bonds are easy to break under heat and oxygen. Furthermore, as a new generation water-reducing agent, the PC water-reducing agent would face the problem of short resources in the near future for nonregenerate ability of crylic acid derived from petroleum, so melamine superplasticizer has shown great advantage. Melamine superplasticizer is one of the most commonly employed due to its colorless, nontoxic, and good thermal stability [5–8]. However, the application of traditional melamine water reducing agent is becoming less and less due to the complex production process, high cost, and relatively inferior slump loss. Along with the architecture industrial development and on the concrete performance requirements to improve, the development of high performance superplasticizer

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