For concrete applications, water reducers are classified broadly into two categories: normal water reducers, and high-range water reducers. The normal water reducers are also called plasticizers, while the high-range water reducers are called superplasticizers. Plasticizers can reduce the water requirement by 5 - 15%, and superplasticizers by 15 - 40%. Sodium and calcium lignosulfonate salts are an example of plasticizers, and sulfonated naphthalene formaldehyde (SNF), and polycarboxylic ether (PCE) are examples of superplasticizers.

Lignosulfonates are generally regarded as 1st-generation water reducers, SNF, 2nd-generation, and PCE’s, 3rd-generation water reducers. A lignosulfonate is a metallic sulphonate salt derived from the lignin recovered from processing wood waste. The resultant aqueous solution of lignosulfonic acid, simple sugars, starches, and natural gums is known as lignin liquor. The composition of the liquor is dependent on the wood species (hardwood, softwood) and the reaction conditions. Performance of the liquor as a plasticizer or retarder is dependent upon the proportioning of these compounds, their molecular weights, and the degree of sulfonation. Sodium lignosulphonates have less of a retardation effect than calcium lignosulphonates.

The mechanism of water reduction is different among the types of water reducers. Lignosulfonates and SNF-based water reducers work on the mechanism of lowering zeta potential, which leads to electrostatic repulsion to disperse the cement particles. PCE water reducers on the other hand, cause dispersion of cement particles by steric hindrance.

Olive & Branch M&D offers a sodium lignosulfonate plasticizer, that has superior dispersing and binding properties. Visit our Plasticizer product page below to learn more about this product.