The price of concrete admixture’s raw materials has been rising rapidly recently. This has caused the concrete industry to rethink its use of polycarboxylate concrete admixture. Polycarboxylate water reducing admixture (PCE) is a versatile concrete admixture with many benefits. It can improve the strength, other physical and mechanical properties of concrete and mortar. It can also save cement and replace special cement, accelerate the early strength development of concrete and adjust the hydration heat release rate of cement. It can also improve the workability of concrete, such as slump retention for longer periods of time and pumping ability.

PCE is a synthetic high-performance plasticizer based on a polycarboxylic acid main chain and grafted with different lengths of side chains derived from maleic anhydride. The negatively charged polymer backbone adsorbs onto the positively charged colloidal particles of unreacted cement, especially the tricalcium aluminate (C3A) mineral phase. This interaction creates a double electric layer that repels the water molecules and keeps the cement slurry in a thick colloidal suspension.

Unlike polynaphthalene sulfonate (PNS) or lignosulphonate, which are commonly used as water-reducing admixtures, a PCE admixture has no retarding effect and can be easily adjusted to suit various types of concrete. It also has good compatibility with fly ash and other raw materials.

Moreover, a PCE admixture can be formulated with a defoamer to control unwanted air entrainment. This makes it an excellent choice for air-entrained concrete applications. In fact, some studies have shown that using a PCE admixture can replace both a PNS/lignin water-reducing product and an air entraining agent (AEA) at one-third the dosage rate, while meeting required air contents.