Various types of chemical admixtures are used to improve the structural properties of concrete such as processability, pumpability, solidification properties, mechanical properties, freeze-thaw resistance, and shrinkage. In addition, chemical admixtures can be used to make and build special concretes such as high flow concrete, high strength concrete, underwater concrete, and shotcrete.
In 1981, polycarboxylate comb polymer (PCE) was invented as a new type of concrete superplasticizer, which is clearly a milestone in concrete technology. With the help of these mixtures, it is now possible to formulate very advanced concrete, for example, ultra-high-strength concrete (UHPC) with a compressive strength of 150 MPa or compacted self-compacting concrete (SCC). In addition, specific PCE molecules are designed to provide a long slump (2 hours) for ready-mixed concrete without sacrificing early strength. These examples illustrate the extraordinary contribution of PCE superplasticizers to modern concrete technology.
PCEs are comb-shaped polymers that can be individually adapted as necessary. The negatively charged polymers absorb to the surface of the cement, shifting its surface potential towards more negative values while the side chains create a form of spatial protection. Both properties increase the clearance intervals and mobility of the cement particles in the cement paste of fresh concrete. This leads to significantly higher water reduction and far greater plasticizing than encountered with conventional superplasticizers or plasticizers based on naphthalene or melamine condensates. Our cooperative manufactures advanced polymers in-house based on its own patented processes, enabling it to offer a wide range of PCE-based superplasticizers.