Wetting agent surfactant plays an important role in the wetting process of pigment

2021-03-05 17:02:02

Both wetting agent and dispersant are surfactants. Wetting agent plays a role in the wetting process of pigment, which can reduce the interfacial tension between liquid and solid, improve the dispersion efficiency of pigment and shorten the grinding time. Low molecular weight has high wetting efficiency. Dispersants play an important role in the process of pigment dispersion and stabilization. They can be adsorbed on the surface of pigment ions to form charge repulsion and steric hindrance effects, which make the dispersion in a stable state.

Coating and ink are water-based and solvent-based, so wetting agent dispersant is also water-based and solvent-based. According to molecular weight, wetting dispersant can be divided into low molecular weight and high molecular weight. Low molecular weight wetting dispersant generally refers to low molecular weight compounds with molecular weight less than several hundred. The wetting dispersant of the molecular chain refers to the high molecular weight compound with molecular weight of tens of millions or even millions and surface activity. In order to distinguish two types of molecular weight wetting dispersants, they are called new high molecular weight surfactants. The wetting dispersants with low molecular weight and high molecular weight are different in structure and application principle.

Leveling agent is a common coating additive, which can promote the coating to form a flat, smooth and uniform film in the process of drying. There are many kinds of leveling agents, and the types of leveling agents used in different coatings are not the same. After the coating is applied, there is a process of flowing and drying to form a flat, smooth and uniform film. Whether the film can achieve the characteristics of smoothness is called leveling. Shrinkage is one of the characteristic defects in the process of leveling and film forming. To improve the leveling property of the coating, it is necessary to adjust the formulation and add appropriate additives to make the coating have appropriate surface tension and the ability to reduce the surface tension gradient.

Anti sagging agent is a kind of compound that can improve the viscosity of paint and prevent sagging during the curing or construction process of paint. Most of these compounds can make the paint have thick deformation. The modified clay is the main thixotropic agent of alkyd coatings. The modified bentonite forms the gel structure through hydrogen bond in the paint. They can be added to the abrasive, destroy the aggregate structure by grinding, or add it in a pre gelation manner.