Superplasticizers are chemical additives used in cement and concrete production to reduce the amount of water needed, resulting in a stronger finished product and lower costs. They come in four main chemical groups and create dispersion between cement particles and water. While they have advantages such as slower setting times and efficient delivery, they must be added on site, which can be costly and result in loss of consistency.
Superplasticizers are a type of linear polymer chemical additive used in cement and concrete production as high-end water reducers. This simply means that superplasticizers reduce the amount of water needed to make cement and concrete products workable. The result is the creation of a free flowing wet concrete mix and a stronger finished product. Furthermore, the reduced water content also requires less cement mix, thus lowering costs.
Chemically speaking, superplasticizers come in four main chemical groups, all of which include sulfonic acid as a component of the polymer: polycarboxylate derivatives, melamine-sulfonated formaldehyde (SMF) condensates, naphthalene-sulfonated formaldehyde (SNF) condensates ) and modified lignosulfonates (MLS ). As a linear polymer, the superplasticizer creates dispersion between the cement particles and the water content of the mix by neutralizing the ionic charge of the cement particles. When this happens, the concrete particles and water are separated, making the concrete flow more freely with a lower water content.
Adding a superplasticizer to a cement or concrete mix creates slightly slower setting or drying times. When coupled with the high slump value of superplasticizer enriched concrete products, it is understandable how these two characteristics can be beneficial to the concrete and cement industry. Adding superplasticizers to the cement plant mixer allows the cement to remain workable for a longer period of time, reducing the amount of water that has to be transported to a construction site. Additionally, the ability of superplasticizers to create free-flowing cement-concrete mixes that are essentially self-leveling makes the delivery of these products more efficient.
Despite the obvious advantages of superplasticizers, these products have some disadvantages. For optimal performance and to avoid loss of consistency, superplasticizers must be added on site, immediately before delivery of the concrete. Unfortunately, this comes with the added expense of special equipment, little control over the uniform addition of superplasticizers, and often involves adding extra water to the mix. The addition of superplasticizers in the concrete and cement plant reduces these risks and the wear of the truck mixer. This may, however, result in slump being lost before it reaches the customer’s job site.
Protect your devices with Threat Protection by NordVPN
