The differences between emulsion type and water-soluble acrylic resin.

In fact, water-based resins can be classified into water-emulsion type, water-dispersed type and water-soluble type according to their appearance. Many people think they are the same resin, but in fact, they are not. Not only are their appearances different, but their uses and properties are also very distinct.

At present, some vague concepts have emerged in society, referring to all water-based resins as water-soluble resins. Waterborne acrylic resins are generally divided into waterborne emulsion type acrylic resins and waterborne solid acrylic resins. Water emulsion type resins are prepared by adding emulsifiers. Water-soluble resins achieve self-emulsification by the hydrophilic groups on the polymer chains. Water-dispersible resins fall between the two types, with a small amount of emulsifier added and insufficient hydrophilic groups. They rely on external forced power, such as high-speed stirring for dispersion, or use ultrasonic waves to achieve water dispersibility. Therefore, its particle size and transparency also lie between the previous two. The water emulsion type is oily and usually appears milky white. Water-soluble resin is transparent and is a true solution in a molecular-level dispersed state, belonging to a nano-scale dispersed state.

Acrylic resin features excellent light resistance, weather resistance, no yellowing, and long-term high gloss maintenance. It can also be modified through grafting, copolymerization, and blending with other monomers and polymers to achieve superior water resistance, chemical resistance, anti-fouling, and anti-corrosion properties. It is widely used in many fields such as coatings, adhesives, inks, textile and leather auxiliaries.

The structures and properties of water-emulsion acrylic resins and water-soluble (including water-dispersible) acrylic resins are different, and thus their applications are naturally distinct. Water emulsion type resins are relatively oily and can only be dispersed in water by being encapsulated with surfactants, namely emulsifiers. Therefore, when they are used in combination with other resins and additives, special care should be taken to prevent this coat from being stripped off by temperature, stirring force, or adsorption and reaction by external substances, thus avoiding demulsification and flocculation. Water-soluble resins, due to the presence of many polar groups in their molecular chains, such as hydroxyl groups, carboxyl groups, sulfonic acid groups, amino groups, amide groups, hydroxymethyl groups, vinyl oxide groups, etc. Therefore, water dispersions and water-soluble resins possess certain polymer surface activity. The surface activity varies depending on the proportion and distribution of hydrophilic and hydrophobic groups, such as wetting and dispersion, emulsification and defoaming, penetration and adsorption, etc. Selecting additives and compounding conditions based on the structural properties of these water-soluble resins can enable them to find ideal applications in coatings, adhesives, textile and leather auxiliaries. The application range of water emulsion resins is narrow (5-40 degrees). Beyond this range, demulsification may occur. Water-soluble resins have a wide range of operating temperatures, can withstand freeze-thaw cycles and heat resistance, and can achieve better performance and a wider range of applications than water emulsions. For instance, the water-based wood paint we have developed can withstand boiling water, soaking in water at 68-72 degrees Celsius, 95% medical alcohol and 4. The paint film remained intact after 30 days in a 5% iodine-containing salt water solution. The hardness reaches 2H, with an impact resistance of 50cm. The paint film is full and smooth, and can fully rival solvent-based PU paint.