Film-forming additives and their applications in latex paint coatings (4)

5 Highly environmentally friendly biodegradable film-forming additives
biodegradable materials are materials that can be completely decomposed by microorganisms into low-molecular compounds under appropriate and indicative natural environmental conditions. Fully biodegradable materials can be completely decomposed by microorganisms and have a positive effect on the environment.
environmental protection film additive products have non-toxic environmental characteristics, to reduce the VOC effect of coatings is significant. As an efficient film-forming additive for all types of water-based latex and dispersive coatings, it is particularly effective in light and semi-gloss paints. It is a special polymerizer and solvent for latex coatings, which gives latex paint the best polymeric properties. It is ethylene acetate, acrylic fat, styrene-acrylic lipids and other polymers of strong solvents, water solubility is small, lower than the rate of water volatility, to ensure that it is fully absorbed by latex particles, forming an excellent continuous coating film, thus giving latex paint the best polygene and color display, while having good storage stability. The product has high boiling point, good solubility, moderate volatility rate, excellent fusion and coupling ability, and significant effect on improving the leveling, gloss and fullness of coating film. Products can dissolve both water-repulsive compounds, but also dissolve water-soluble compounds, so there is a "one-world solvent" called. As a green film additive, the product has been optimized, in latex paint, it can effectively gather, soften, fuse emulsion particles, so that the film temperature of emulsion greatly reduced, conducive to the construction of latex paint applications. In addition, environmental protection film additive products for pigment addition, not only has a certain wet dispersion effect, but also can improve the uniformity and stability of pigments in latex paint, for the paint film anti-scrub performance, freeze-thaw stability, adhesion, mechanical strength have a certain role in promoting.
A good film-forming agent must have the following properties: it is an active solvent of polymer parts in a coating; The film-forming nature of high-polymers is related to temperature, each high-polymer has its own film-forming temperature, below which the high-polymer will not become a film. This temperature is called the minimum film-forming temperature of a highly polymer. Some highly polymers have very low minimum film-forming temperatures and are easy to film-forming, but are not suitable for coatings. If the high-polymer is to form a film below the minimum film-forming temperature, a film-forming agent must be added to the high-polymer. In the design of coating formulation, it is necessary to take into account the harsh temperature and humidity conditions, the use of mixed solvents can change the hardness of the paint film, the amount of film-forming agent affects the drying time of the paint film and the performance of the final paint film.
main component of AH-12, an environmentally friendly film-forming additive, is ester compounds, which have non-toxic and environmentally friendly properties and have a significant effect on reducing voC in coatings. As an efficient film-forming additive for all types of water-based coatings and dispersive coatings, it is particularly effective in light and semi-gloss coatings. Environmentally friendly film-forming additive AH-12 is a strong solvent of various polymers such as ethylene acetate, acrylic, styrene-acrylic lipids, water solubility is small, less volatile than water, easy to be absorbed by latex particles, forming an excellent continuous coating film, thus giving latex paint the best polysexuality and color display, while having good storage stability. Environmentally friendly film-forming additive AH-12 has a high boiling point, good solubility and moderate volatility rate, and has excellent fusion and coupling ability, which has remarkable effect on improving the leveling, gloss and fullness of coating film. In addition, environmentally friendly film-forming additive AH-12 for pigment addition, not only has a certain wet dispersion effect, but also can improve the uniformity and stability of pigments in latex paint, for the paint film anti-scrub performance, freeze-thaw stability, adhesion, mechanical strength have a certain role in promoting. Environmental protection film additive products are widely used in building coatings, high-grade automotive coatings and automotive repair coatings, electrophoretic coatings, ship container coatings, wood coatings, coils and coiled steel coatings;6 The use of film additives in latex paint
many emulsion production plants have film additives that match them, and if the production plant does not have a supporting additive, the corresponding additive varieties must be determined through testing. In practical applications, two or more film-forming additives are often used together. Film additives on the emulsion has a greater cohesion, so when adding should avoid adding a high concentration of film additives, preferably in the appropriate stage of coating production, so as not to damage the stability of the emulsion, film additives have direct addition, pre-mixing and pre-emulsification to add 3 ways:
directly add. Membrane additives can be added directly to the pigment mixture before adding emulsion, preferably before the coating is ground to disperse emulsification, or after the emulsion is added to the coating, but must be added at a very slow speed and in a stirring state.
premixed to join. In cases where direct addition of film-forming additives can damage the emulsion, it can be premixed with surfactants and propylene glycol before adding. Pre-emulsified addition. For photocinted latex
paints with low pigment volume concentrations, they can be pre-emulsified before film-forming additives are added, emulsified with water, thickeners and dispersants, and then added.7 Conclusion
From the film-aiding process, film-forming additives provide sufficient free volume in the film-forming process to deform polymer particles and the polymer molecular chain segment diffusion, winding and fusion into a continuous film. According to the theory of free volume, the amount of film-forming additives can be estimated by formula. However, the reality is that different film-forming additives on the same emulsion to reduce the minimum film-forming temperature is different, it is clear that the other properties of film-forming additives also have a significant impact. Film-forming additives play an extremely important role in latex paint, especially the study of the role of film-forming additives is particularly important. The water-soluble
compatibility and volatility of film-forming additives affect the presence, movement and use of film-forming additives in coatings. Studying the effects of film-forming additives on emulsion coatings will be of great help to a deep and detailed understanding and grasp of the film-forming process of water-based coatings, to improve the film-forming properties of coatings, to reduce the dosage of film-forming additives, and to develop environmentally friendly coatings such as low VOC or zero VOC..