BDMA in epoxy resin, mainly used to promote the curing system of acid anhydride, polyamide, aliphatic amine, etc., to accelerate the curing of products, widely used in epoxy resin electronic potting materials, encapsulation materials, epoxy floor coatings, marine paint used as curing accelerator.
Generally speaking, this type of dispersant consists of at least one anchor group and a three-dimensional backbone. The simplest types are oleic acid and soybean lecithin, and then synthetic dispersants  are used. The stability of adsorbed oleic acid in water dispersion medium is shown in Figure 26-7. The stability of pigments adsorbing natural or synthetic additives in non-aqueous media is shown in Figure 26-8. Since the 1950s, organic pigments have replaced inorganic pigments with environmental issues, such as those containing cadmium and lead. Because organic pigments have a high specific surface area, they are difficult to stabilize, and can achieve high gloss when they have a certain color strength, so a new type of dispersant 117 must be developed, as shown in Figure 26-9. Choose the correct dispersant The main points of preparing color paste and being able to adapt to terminal coatings are pigment solids, compatibility and viscosity.
Stability of colloidal particles adsorbing oleic acid in non-aqueous media
It is very important to understand the performance of various dispersants. Some have good compatibility and are used in organic and inorganic pigments.
(Features: increasing molecular weight and anchoring groups) Others have lower viscosity, carnauba wax price and some have higher gloss.
Water-based color paste dispersant
Similar to solvent-based dispersants, water-based color paste dispersants also have at least one anchor group and a three-dimensional main chain. Unlike solvent-based color pastes, water-based color pastes do not use resin. The advantage is diversity and compatibility, but the disadvantage is the decrease in chemical stability. So we can see in the market that decorative coatings usually use resin-free color paste systems, while high-performance industrial paints use resin-containing color pastes. This does not mean that the performance of decorative coatings is poor, but the traditional concept is that a large amount of dispersant and surfactant without resin color paste will have a negative effect on the performance of the coating. In the past, this view was correct.
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