Super dispersants are suitable for aqueous systems

As a special type of surfactant, the molecular structure of a hyperdispersant contains two groups that are opposite in solubility and polarity, one of which is a shorter polar group called a hydrophilic group. Its molecular structure characteristics make it easy to orient and arrange on the surface of a substance or at the interface between two phases, reducing interfacial tension and having a good dispersion effect on aqueous dispersion systems.

The super dispersant suitable for water-based systems consists of two parts: lipophilic and hydrophilic. In order to achieve good dispersion effect, the molecular weight of the hydrophilic part is generally controlled at around 3000-5000. If the hydrophilic chain is too long, the super dispersant molecules are easily detached from the pigment surface, and the hydrophilic chains are prone to entanglement and flocculation; The molecular weight of the hydrophobic part is generally controlled between 5000 and 7000. If the hydrophobic chain is too long, it often cannot fully adsorb onto the particle surface and form a ring or bind with adjacent particle surfaces, resulting in "bridging" flocculation between particles. The suitable proportion of hydrophilic parts in the polymer dispersant chain segment is 20% to 40%. If the proportion of hydrophilic ends is too high, the solvation of the dispersant will be too strong, the binding force between particles and dispersants will be relatively weakened, and dispersants will easily fall off; On the contrary, if the proportion of hydrophilic end is too low, the dispersant cannot be completely dissolved in water, and the dispersion effect decreases.

For diameters ranging from 0.1 to 10&Particles with a thickness of 5-20nm can provide sufficient repulsive force to stabilize the particles. Having anchoring groups and soluble dispersant chains are important elements in the composition of polymer dispersants. The adsorption forms of copolymers with different structural types on particle surfaces are not the same. Polymers that can effectively stabilize should have a structure where one end is anchored to the particle surface and the other end can freely stretch in the solvent.