In 1930s, it was found that adding sulfite pulp waste liquid into concrete can improve the workability, strength and durability of the mixture. 1935, a water reducer with lignosulfonate as the main component was first developed by E.W. Shengdian in the United States, and 1937 was patented} s}, which was widely used in slipform concrete, dam concrete and winter construction concrete in the United States in the 1950s. 1962, the Japanese Hattori Jianyi Company developed the water reducer with the sodium salt of R-tea sulfonic acid formaldehyde condensate as the main component for the first time, referred to as tea water reducer. This water reducing agent has the characteristics of high water reducing rate, and is suitable for preparing concrete with high strength (compressive strength 100 MPa) or slump greater than 20. Subsequently, in 1964, the Federal Republic of Germany successfully studied sulfonated melamine formaldehyde resin water reducer. This water reducing agent has the same characteristics as tea water reducing agent, with high water reducing rate, good early strength effect and low air permeability. At the same time, it has good adaptability to steam-cured concrete products and cement products with high aluminate content (mainly C3A), and can be used to prepare high-strength or high-fluidity concrete. Germany invented flowing concrete, which made concrete develop from manual pouring or hanging pot pouring to pumping construction, saving manpower, improving work efficiency, ensuring quality, eliminating noise, and the technical level and construction level of concrete have made a great leap.
Due to the important contribution of superplasticizer to concrete modification, its application has become the third major breakthrough in the history of concrete development after reinforced concrete and prestressed concrete. Marked by the development and application of superplasticizer, concrete technology has entered the third generation from plasticity, hardness to fluidization.
In the early 1990s, the concept of high performance concrete (HPC) was first put forward in the United States, which required high strength, high fluidity and high durability of concrete. High performance concrete puts forward higher requirements for water reducing agent, which requires high water reducing rate, high fluidity and small slump loss over time. Some new superplasticizers have been developed and applied rapidly, such as polyaspartic acid and sulfamic acid superplasticizers. China's blending started a little later than foreign countries, but it developed rapidly. In 1950s, the research and application of lignosulfonate and air entraining agent began. After 1970s, both tea water reducer and onion water reducer had their own products. In the late 1990s, modified melamine, sulfamate and aliphatic superplasticizer developed rapidly. Since 2006, driven by the construction of high-speed railway, polyaspartic acid series high-performance water reducer has also made rapid development. Water reducing agent promotes the development of new concrete technology and the application of industrial by-products in cementitious materials system in China, and gradually becomes an essential material for high-quality concrete.