Waterborne epoxy coatings are coatings in which water is the solvent or dispersion medium. Waterborne epoxy coatings include water soluble epoxy coatings and water emulsion coatings. Water-soluble coatings are often also called electrophoretic coatings, that is, the resin dissolves in water to form a uniform colloidal solution. If the resin ions are charged, the colloidal particles can be electrophoretically deposited on the surface of the workpiece under the action of direct current. According to the decentralized system, it can be divided into: 1) Water-soluble epoxy coatings Water-soluble epoxys can be further divided into water-soluble anionic resin coatings (anode electrophoretic coatings) and water-soluble cationic resin coatings (cathode electrophoretic coatings). Water-soluble curing agents such as melamine formaldehyde resin, benzoguanamine formaldehyde resin, urea-formaldehyde resin and isocyanate blocking are often used. a)The resin of the water-soluble anionic resin coating is reacted with an acid or an acid anhydride of an epoxy resin having a high hydroxyl group content, and neutralized with an amine to obtain a water-soluble anionic resin. b)The resin of the water-soluble cationic resin coating is obtained by adding an epoxy resin to an amine, introducing a semi-blocked polyisocyanate as a crosslinking agent, and finally neutralizing with an acid. 2) Water-based epoxy coatings Water-based epoxy coatings emulsify lower molecular weight epoxy resins with suitable emulsifiers and have good storage and stability. Most of the practical medium temperature curing types are water emulsion coatings. Sinograce Chemical produces water based coating,Water-based glue, polyurethane coating visit us sinograce chemical: https://www.sinogracechem.com Get a Quote Now :sales@sinogracechem.com Telephone               :+86 0551 63459511

Classification and characteristics of water-based coatings - water-based alkyd paints The vegetable oil is reacted with an acid anhydride after alcoholysis to form an alkyd resin, and the content of the hydrophilic group can be increased to form a water-soluble or water-dispersible resin.Water-soluble water-based alkyds are quite transparent in appearance but have color,The alkyd emulsion was brown and yellow and opaque. The unsaturated bond in alkyd resin is the basic guarantee of excellent properties.Like the solvent-type alkyd, the performance of the coating can be adjusted by the length of the oil. The oiliness is short, the drying is fast, the gloss is high, the hardness of the paint film is large, the oiliness is long, the flexibility of the paint film is good, and the impact resistance is good.Therefore, water-based alkyd can be divided into short oil degree and long oil degree. Alkyd resins have a good permeability to wood and are particularly suitable for making water-based colorants.Another advantage of water-based alkyds is the use of oxygen in the air to cross-link the curing, so the solvent resistance of the paint film is much better than that of other single-component water-based paints.Acrylic modified waterborne alkyd is an acrylic monomer which is incorporated into the molecule during the synthesis of alkyd, and the gloss retention of the modified alkyd resin is remarkably improved.Recently, in order to further improve the performance of waterborne alkyd paints, an alkyd/acrylic hybrid technology has been developed to form a core shell system in which an alkyd polymer is a core and an acrylic polymer is a shell, the hydrophilic acrylic shell protects the alkyd core from hydrolysis.After the coating, the water in the paint evaporates, and the fine particles of the emulsion penetrate into the micropores of the wood, and the linear polymer molecules are further oxidized and crosslinked to form a film. The aqueous urethane oil is an alkyd resin modified with a diisocyanate.The diisocyanate reacts with the hydroxyl group of the alkyd resin to form a polyurethane structure, which has the properties of certain polyurethanes while retaining the characteristics of oxidative crosslinking of the alkyd resin. The one-component water-based paint thus produced is convenient to construct and has excellent performance. One of the finevarieties in water-based paints. Sinograce Chemical produces water based coating,Water-based glue, polyurethane coating visit us sinograce chemical: https://www.sinogracechem.com Get a Quote Now :sales@sinogracechem.com Telephone               :+86 0551 63459511

Classification and characteristics of waterborne coatings - waterborne polyurethane coatings Polyurethane is a general term for a class of macromolecular compounds having a carbamate structure in a molecular structure, and is usually produced by a polyaddition reaction of a diisocyanate and a polyol. In view of the variety of isocyanates and polyols, the resulting polyurethanes can range from soft to hard, from brittle to tough, from highly elastic to rigid in a variety of forms. Polyurethane coatings also have a wide range of performance adjustments.Depending on the type of isocyanate used to prepare the polyurethane, the polyurethane emulsion and the corresponding lacquer can be classified into two major categories, aliphatic and aromatic.The aliphatic paint film has excellent weather resistance and yellowing resistance, and can be used as an outdoor decorative paint; aromatic waterborne polyurethane is mostly used for interior decoration paint.The polyol used is a polyether polyol, a polyester polyol, a polyolefin polyol, etc.,thus, the title of polyether polyurethane waterborne coating, polyester polyurethane waterborne coating, etc. A hydrophilic group or a hydrophilic segment must be introduced during the synthesis of the aqueous polyurethane.The most common hydrophilic groups are anionic carboxylic acid groups and sulfonic acid groups; macromolecular backbones and side chains may also have cationic groups such as quaternary ammonium ions; or nonionic polyoxyethylene long segments and The hydrophilic group hydroxymethyl group, the corresponding aqueous polyurethane is called anionic, cationic and nonionic.The particle size obtained by polymerization is polyurethane emulsion and polyurethane dispersion (PUD). The latter usually has a nanometer particle size, and the appearance is translucent or completely transparent. It is one of the best waterborne wood lacquer bases. It is specifically referred to as a nanoemulsion to distinguish it from a normal emulsion that is white in appearance. Waterborne polyurethane has excellent flexibility after film formation. It is often blended with a relatively rigid acrylic emulsion. The obtained waterborne wood lacquer has the advantages of both, especially in the film formation at lower temperatures. Better paint film hardness.A better method is to introduce an acrylic monomer in the process of preparing the polyurethane dispersion to form a core-shell structured particle in which the polyacrylate is a core and the polyurethane is a shell.This polyurethane-acrylic dispersion (PUA) is considered to be a fourth-generation polyurethane dispersion, specifically called a hybrid , which is better than a blend of acrylic emulsion and polyurethane dispersion, mainly in distribution. The paint is more stable, has better low-temperature film formation, no stickiness, high hardness, good flexibility, good adhesion, etc., and has been widely used. The aliphatic polyurethane dispersions represented by Sinograce Chemic...

Classification and characteristics of waterborne coatings - Waterborne acrylic coatings The emulsifier that USES when polymerization can be anionic, also can be nonionic or cationic, corresponding latex and the lacquer that make also can call anionic, nonionic or cationic. Acrylic waterborne wood lacquer is a variety of applications that have been used earlier and are still in large quantities. Since the beginning of the widespread introduction of acrylic architectural latex paints in the 1970s, waterborne acrylic wood lacquers have also appeared on the market. Acrylic emulsion is formed by polymerization of vinyl monomers with acrylate monomers as main monomers. Various additives such as an emulsifier, a stabilizer, and a pH adjuster are added during the polymerization, and the system is quite complicated. The distribution of hard and soft chain segments of polymer molecules in emulsion particles can be controlled by using different monomers, adjusting the dosage and changing the feeding method, so as to obtain emulsions with different vitrification temperature (Tg) or different minimum film-forming temperature (MFFT). The emulsifier used in the polymerization may be anionic or nonionic or cationic, and the corresponding emulsion and the resulting lacquer may also be referred to as anionic, nonionic or cationic. Acrylic emulsion is obtained by polymerization of acrylic monomer only, and the paint is called pure acrylic water paint. Other vinyl monomers can be added to modify the emulsion during polymerization. For example, styrene can be added to improve the hardness of paint film and reduce the cost. Fluorine-containing and silicon-containing monomers were introduced to improve the surface properties of the film, reduce the surface free energy of the film, and improve the hydrophobicity and stain resistance. Thus the production of benzene acrylic water based paint, fluorocarbon water based paint, silicon acrylic water based paint and other varieties. The paint film made of acrylic emulsion has good weather resistance, is not easy to yellow, has high hardness and good gloss. However, its main disadvantage is that the anti-blocking property is poor, and it is prone to hot sticky and brittle. When the hardness is too high, the low-temperature film forming property is not good, and it is difficult to carry out coating construction in winter. Further improving and improving the properties of the acrylic emulsion by self-cross linking polymerization, soap-free polymerization, core-shell polymerization, etc., especially using the core-shell technique, the emulsion particles are made into a hard core soft shell or a soft core hard shell structure, and even The multi-layer structure of soft and hard to meet the needs of different construction and use conditions. Sinograce Chemical produces water based coating,Water-based glue, polyurethane coating,Acrylic solution . visit us sinograce chemical: https://www.sinogracechem.com Get a Quote No...