Concrete superplasticizers are chemical admixtures that dramatically reduce the water content of concrete. They transform stiff low-slump concrete into flowing, pourable, easy-to-place concrete and improve workability, speed finishing and help to increase strength, conserve cement, reduce shrinkage and thermal cracking. They are commonly used in the manufacture of ready-mix concrete, precast concrete and shotcrete. There are many types of superplasticizers available in the market such as sulphonated naphthalene, polycarboxylate and lignosulfonates. Fritz-Pak offers two types of sulphonated naphthalene superplasticizer: Supercizer 1 and Supercizer 5.

The main advantages of using sulphonated naphthalene plasticizers are that they have very high permeability and excellent flowability properties, even at very low dosages. They are also less sensitive to temperature than other superplasticizers and can be added at the point of concreting.

In contrast to traditional sulphonated plasticizers, the addition of NSF does not have a significant effect on the setting time of concrete. The only exception is when using lignosulfonate based superplasticizers which can retard initial set by about an hour.

Another advantage of NSF is that the concrete containing it has much higher early strength than conventional concrete. This is due to the fact that the NSF promotes the hydration reaction of cement by providing more hydration sites. The early strength is also boosted by the fact that NSF reduces slump loss at the time of placement. Slump loss is caused by the evaporation of water from the concrete during transport and handling. Adding NSF to the mix at the final stage of concreting prevents this slump loss and maintains fresh concrete slump until discharge at site.