What are the differences between the various types of water-based acrylic resins?

In the current society, some vague concepts have appeared, and water-based resins are generally referred to as water-soluble resins. In fact, water-based resins can be divided into water-emulsion type, water-dispersed type and water-soluble type according to their appearance. Many people think that it is the same resin, but it is not, not only the appearance is different, but also the use and characteristics are very different.

Water-based acrylic resins are generally divided into water-based emulsion-type acrylic resins and water-based solid acrylic resins. The water-emulsion resin is prepared by adding an emulsifier, and the water-soluble resin is realized by self-emulsifying with hydrophilic groups on the polymer chain. The water-dispersible resin is between the two. The amount of emulsifier added is small and the hydrophilic group of the band is insufficient. It depends on external force, such as high-speed stirring and dispersion, or ultrasonic waves to achieve water dispersibility. Therefore, its particle size and transparency are also between the former two. The water-emulsion type is oily, generally milky white, and the water-soluble resin is transparent.

Acrylic resin has excellent light resistance, weather resistance, non-yellowing, long-term high gloss performance, and can be modified by grafting, copolymerization and blending with other monomers and polymers to obtain excellent water resistance and chemical resistance. Anti-fouling and anti-corrosion, etc., are widely used in many fields such as coatings, adhesives, inks, textile and leather auxiliaries.

Water-emulsion acrylic resins and water-soluble (including water-dispersed) acrylic resins have different structures, different properties, and naturally different uses. The water-emulsion resin is oily, and it is completely dependent on the surfactant, that is, the emulsifier, to wrap it in order to disperse in the water. Therefore, when they are used in combination with other resins and additives, special care should be taken that the coat is not demulsified and flocculated by temperature, stirring power, or by the adsorption and reaction of admixtures. Water-soluble resin, because there are many polar groups in the molecular chain, such as: hydroxyl, carboxyl, sulfonic acid, amino, amide, methylol, oxyethylene, etc. Therefore, water dispersions and water-soluble resins have certain polymer surface activity. According to the proportion and distribution of hydrophilic groups and hydrophobic groups, the surface activity is different, such as: wetting and dispersing, emulsification and defoaming, osmotic adsorption, etc. are all different. According to the structural properties of these water-soluble resins, the selection of auxiliaries and compounding conditions can make them find ideal applications in coatings, adhesives, textile and leather auxiliaries. The water emulsion resin has a narrow application range (5-40 degrees), beyond this range, it is possible to break the emulsion. The water-soluble resin has a wide use temperature, can withstand the test of freezing and thawing and heat resistance, and can obtain better performance and larger application fields than water emulsion. For example, the water-based wood lacquer developed with water-soluble resin is resistant to boiling water. It is immersed in water of 68-72 degrees, 95% medical alcohol and 4.5% iodized salt solution for 30 days, and the paint film is intact. The hardness reaches 2H, the impact resistance is 50cm, and the paint film is plump and smooth, which is completely comparable to solvent-based PU paint.

1. Water-based emulsion acrylic resins are generally water-based emulsion-type acrylic resins, which are often referred to as acrylic emulsions. Most of these products are reacted with acrylate monomers without methyl, so the glass transition temperature of such resins must be lower than that of solid acrylic resins. They have a lower TG, so in some substrate (soft) applications they are incomparable to other solid acrylics. In particular, the application of softer substrates such as paper and leather is the best embodiment. When they are phenylated and vinegared, they become styrene-acrylic emulsions and vinegar-acrylic emulsions, which are the styrene-acrylic emulsions, vinegar-acrylic emulsions, and pure acrylic emulsions that we often see. In fact, it only refers to adding monomers such as styrene and vinyl acetate during emulsion polymerization, so that they have other more properties. When the pure acrylate is reacted, it is called pure acrylic resin, also called pure acrylic emulsion. Another largest application of these resins is architectural coatings, which account for a large share of the market.

2. Water-based solid acrylic resin, this type of resin is developing slowly in our country! This type of resin is mainly produced in a few companies such as Germany, South Korea, Japan, and Taiwan. They are currently used in paper varnishes and printing inks, and other uses are waiting for new development.