Study on Synthesis and  between Molecular Structure and Performance of Ether-type Polycarboxylate Superplasticizer

The development and progress of concrete admixture technology has played a decisive role in the technological progress of the concrete industry. Throughout the industry, the entire industry has experienced the development of the first generation of ordinary water reducers represented by wood calcium and the second generation of superplasticizers represented by naphthalene series. As the third generation, the latest generation of high performance water reduction The agent, polycarboxylate high-performance water reducer has good performance in water reduction, moisture retention, plasticization, shrinkage and environmental protection, and has become the future development direction of the concrete admixture industry.

In the 21st century, with the vigorous development of the construction industry, the concrete preparation and construction technology at home and abroad has made great progress. The performance of concrete mixes is from the early dry hardness to the plasticity and fluidity of today, and the strength of concrete. The comprehensive performance of low-intensity to medium-high strength and concrete has been developed from ordinary performance to medium-high performance. Various concretes such as high-performance concrete (HPC), self-compacting concrete (SCC) and underwater non-discrete concrete have become more and more widely used. The large trend of large-span, large-volume, high-rise and mechanized construction of concrete structures determines that concrete will develop in the direction of high work performance, high mechanical properties and high durability. The improvement of concrete performance and the advancement of technology are inseparable from the renewal of raw material varieties and the advancement of raw material technology. As the main influence factor in the development of concrete technology today, the development and progress of concrete admixture technology will become more and more important. In practical engineering, the structural parameters of polycarboxylates are designed by selecting different synthesis conditions to functionalize the polycarboxylate superplasticizer (early strength, water reduction, moisture retention, bleed air, etc.) and pass different types of polycarboxylates. The acid water reducing agent is compounded to form a new water reducing agent, which can provide options for concrete raw material adaptability and different engineering applications. For example, high water reducing polycarboxylate water reducing agent is mainly used for large fluidity requirements and high pumping. The commercial polystyrene water reducing agent is mainly suitable for mass concrete, high temperature construction concrete and concrete which needs long distance transportation or long time to be placed; the air entrained polycarboxylic acid water reducing agent is concrete. The system introduces a large number of tiny bubbles, improves the workability of the concrete mixture, reduces bleeding and segregation, and improves the frost resistance and impermeability of the concrete. It is often used for impermeability, frost resistance, severe bleeding, and sulfate attack resistance. Concrete. In addition, since the production process and products of polycarboxylic acid-based high-performance water reducing agent are non-polluting and meet the requirements of green environmental protection, it has also become a key and priority development project not only in developed countries but also in developing countries.