binder fluid

In process engineering, a binder fluid is defined as a liquid containing one or more binders (e.g. polymers, sugars, starch or cellulose derivatives) in dissolved or dispersed form. When wetting powders, it builds up cohesive and adhesive forces between the particles. When the binder fluid comes into contact with a collection of particles, liquid bridges and films are initially formed. During subsequent drying, cooling or chemical curing, the binder solidifies and imparts mechanical strength to the resulting granules, tablets or agglomerates.

In powder mixers – such as those from amixon® – binder liquid is typically sprayed into the moving bulk material in a fine mist, ensuring that each particle is wetted as evenly as possible and resulting in a narrow distribution and strength range for the granules. In this process, the composition (binder content, viscosity) of the binder liquid, the spray pattern and the dosing strategy significantly determine the agglomerate size, dust-free nature and the subsequent disintegration and dissolution properties of the end product.