Generally speaking, matting agent with the paint storage time, will be in a certain degree of stratification and precipitation, the surface of the organic treatment of the product will be better anti-sink performance. Therefore, when designing the formula, we should consider how to avoid the precipitation problem of matting powder and fill in the appropriate anti-sink additives.
The adsorption between pigments and their derivatives L10 is difficult for some organic pigments, such as phthalocyanine blue, dioxazine violet and other polymer dispersants, to adsorb on the surface. If the chemical structure of such pigments is to be changed This type of dispersant is more effective for high molecular weight pigments with large planar structure. In other words, by attaching a polar polymer to the phthalocyanine blue molecule for modification, a polymer dispersant that can be adsorbed on the surface of the phthalocyanine blue can be obtained.
In summary, the interaction between the polymer and the pigment surface includes van der Waals dispersion force, electrostatic force (interaction between ions), chemical interaction between acid/base, hydrogen bonding force, etc. The interaction between the polymer or dispersant and the pigment particles may be pp wax products one force at work, or two or more forces at work.
There are many factors that affect the adsorption of polymer compounds on the surface of pigments. Here are several main factors.
The effect of polymer concentration on adsorption is in different polymer compound solutions,
Vmax~10kT; when y=30mV, a=0.2pm, Vmax~3kT. In these two cases, agglomeration of carbon black can be observed, and the particle size becomes a~1jm. This is because the carbon black has a small particle size and a low energy barrier Vmx x.
Sato et al. studied the relationship between impurity flocculation and test potential in non-aqueous pigment dispersions. He believes that it is difficult for pigments with the same symbol to agglomerate. When different symbols are used, both inorganic pigments are difficult to agglomerate. When inorganic and organic pigments are mixed, agglomeration will occur, and when both are organic pigments, agglomeration will also occur.
Leave a message
We’ll get back to you soon