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PVA is the abbreviation of polyvinyl alcohol, which is a water-soluble polymer material with high hydrophilicity. PVA is often used in the manufacture of cosmetics, paper, glue, coatings, food packaging and other fields. PVA has good solubility. The dissolution method of PVA varies depending on the application field and demand, and each method has its own unique advantages and disadvantages. Choosing a suitable dissolution method can improve the solubility and stability of PVA, making it more widely used in different fields.   1. Temperature rise dissolution method The temperature rise dissolution method is one of the most commonly used methods for dissolving PVA. Add PVA powder to an appropriate amount of water, then stir evenly and heat to an appropriate temperature to completely dissolve the PVA. Normally, the dissolution temperature of PVA is between 60 and 95 ℃. The dissolution temperature of PVA is related to its degree of polymerization and acetate content. The higher the degree of polymerization, the more acetate content, and the higher the dissolution temperature. The solubility and dissolution rate of PVA can be controlled by changing the temperature and time.   2. Dissolution by auxiliary agent In addition to directly adding PVA to water for dissolution, the solubility and stability of PVA can also be improved by adding auxiliary agents. Common auxiliary agents include acetone, methanol, ethanol, phenol, etc. These auxiliary agents can form hydrogen bonds or other interaction forces with PVA, thereby improving solubility. The addition of auxiliary agents can also shorten the dissolution time of PVA.   3. Slow cooling and dissolution The slow cooling method is a special PVA dissolution method, which is suitable for the preparation of polymers, micro-nano particles, films, fibers and other materials. The basic principle of the slow cooling method is to add PVA powder into water, heat it to dissolve it, and then slowly cool it down to make the PVA molecules self-assemble to form nanoparticles, nanofibers or films. The slow cooling rate has an important influence on the self-assembly process of PVA. Generally speaking, the slower the slow cooling rate, the more complete the structure of the PVA self-assembly. The slow cooling method is mainly suitable for the preparation of micro-nano materials.   4. Gas phase dissolution The gas phase method is a relatively new PVA dissolution method. In this method, the PVA solid enters the atmosphere through the dissolution hopper. By controlling the temperature, pressure and atmosphere composition, the PVA solid is directly evaporated into gaseous molecules, and then transported to other equipment through a transmission pipe for reaction or solidification to form a corresponding block. Unlike the traditional dissolution method, the gas phase method can prevent the PVA molecules from being affected by water decomposition, thereby maintaining the integrity and quality of the material.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com ElephChem Holding Limited, professional market expert in Polyvinyl Alcohol(PVA) and Vinyl Acetate–ethylene Copolymer Emulsion(VAE) with strong recognition and excellent plant facilities of international standards.

EVOH (ethylene-vinyl alcohol copolymer) is a polymer material produced by copolymerization of ethylene and vinyl alcohol. Since the polar hydroxyl groups on the EVOH molecular chain can form hydrogen bonds with water molecules, it can block moisture, while its non-polar vinyl groups can effectively block gases.   EVOH has good processing properties and can be blended or compounded with various plastics such as PE, PP, PET, etc. to produce blended or composite materials with excellent performance. It also has good thermal stability and can be processed at high temperatures. It has excellent transparency, which makes the contents of the package clearly visible and easy for consumers to check. It can be completely recycled and reused, and can also be biodegraded to reduce pollution to the environment. Due to its excellent barrier properties and environmental protection, EVOH is widely used in the field of food packaging. For example, it is widely used in vacuum packaging, food cans, beverage bottles and other fields.   EVOH is also widely used in the field of medical packaging, such as pharmaceutical packaging, medical dressing packaging, etc. Its excellent barrier properties can effectively extend the shelf life of drugs and medical dressings. In addition, EV0H is also widely used in the fields of cosmetic packaging, pesticide packaging, etc.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com ElephChem Holding Limited, professional market expert in Polyvinyl Alcohol(PVA) and Vinyl Acetate–ethylene Copolymer Emulsion(VAE) with strong recognition and excellent plant facilities of international standards.

Vinyl acetate-ethylene copolymer emulsion is a polymer emulsion made of vinyl acetate and ethylene as basic raw materials, referred to as VAE emulsion or EVA emulsion in English. Since its introduction in 1965, it has been widely used in adhesives, building materials, coatings, papermaking, fabric processing, tobacco, packaging and other fields due to its excellent adhesion, permanent flexibility, good acid and alkali resistance and other properties.   In order to improve the performance of VAE emulsion and expand its application range, a lot of fruitful modification research has been done to improve the water resistance, mechanical strength, heat resistance, adhesion, curing speed and other aspects of VAE emulsion. These modification studies are mainly focused on the following directions: additive method, copolymerization method, composite modification method and blending method. Among them, the blending method is a method of physically blending VAE emulsion with one or more polymer solutions or emulsions to form a multi-component system. The properties of the various components of the blending method can complement each other, thereby obtaining new materials with better performance or new properties, reducing costs while potentially expanding the application field of VAE emulsion, allowing VAE emulsion to play a greater application value.   Polymer solutions or polymer emulsions that are often blended with VAE emulsions include: rosin resin, phenolic resin, urea-formaldehyde resin, terpene resin, polyurethane emulsion, acrylic emulsion, styrene-acrylic emulsion, vinyl acetate emulsion, styrene-butadiene emulsion, etc. Since VAE emulsion has good miscibility with a variety of emulsions, blending is the simplest and most direct way to achieve complementary properties of the blended components and obtain new properties.   PVAc emulsion was used to modify VAE emulsion, and at the same time, thickening resin and additives were used to synthesize an adhesive suitable for bonding non-polar plastic materials. The addition of thickening resin significantly improved the bonding strength of the emulsion; the addition of acidic metal salt crosslinking agent improved the water resistance of the system without affecting the stability of the emulsion.   VAE emulsion was modified by blending pure acrylic emulsion, acetic acid acrylic emulsion, silicone acrylic emulsion, styrene acrylic emulsion and VAE emulsion to prepare adhesive. The results show that the VAE emulsion modified by acrylate emulsion has been greatly improved in bonding performance and peel strength. Among them, the adhesive obtained by using acetic acid acrylic emulsion to modify VAE emulsion has the best comprehensive performance, especially the most obvious improvement in high temperature adhesion.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com ElephChem Holding Limited, professional market expert in Polyvinyl Alcohol(PVA) and Vinyl Acetate–ethylene Copolymer Emulsion(VAE) with strong recognition and excellent plant facilities of international standards.  

PVA block copolymer is a polymer with high application value. It is composed of polyvinyl alcohol (PVA) and another organic polymer block. PVA is a colorless, odorless, non-toxic synthetic polymer with good solubility and plasticity. It has good solubility and gelling ability in water and can form strong hydrogels. Therefore, PVA is widely used in fields such as textiles, paper, adhesives, medical supplies, etc.   The choice of another organic polymer block can be determined according to needs. For example, organic polymers with specific functions such as polyacrylate (PAA), polyacrylamide (PAM), etc. can be selected. These organic polymers have different chemical properties and application characteristics, and can play different roles in block copolymers.   The preparation methods of PVA block copolymers include solution copolymerization, emulsion copolymerization, reaction impregnation, etc. Among them, solution copolymerization is one of the most commonly used methods. During the preparation process, PVA and other organic polymers are first added to the solvent in a certain proportion, and then the two polymers are copolymerized by controlling the temperature, reaction time, acid-base balance and other conditions. The final product is a block copolymer with good properties and application value.   The application of PVA block copolymer is very wide. For example, it can be used to prepare highly absorbent materials such as household paper, sanitary napkins, diapers, etc. In addition, it can also be used to prepare medical dressings, drug sustained-release systems, capsule materials, etc.   In general, PVA block copolymers have high research and application value. By rationally selecting blocks and regulating the preparation method, copolymers with specific functions and properties can be obtained to meet the needs of different fields.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com ElephChem Holding Limited, professional market expert in Polyvinyl Alcohol(PVA) and Vinyl Acetate–ethylene Copolymer Emulsion(VAE) with strong recognition and excellent plant facilities of international standards.  

The modified polyvinyl alcohol coated composite film is colorless and has good transparency. It has excellent oil resistance and organic solvent resistance. It has good antistatic properties. It can be used for microwave heating and metal detection of packaged food. It has excellent aroma preservation performance, which can maintain the original flavor of the food in the bag for a long time, and at the same time effectively prevent the odor outside the packaging material from entering the packaging bag.   It has excellent barrier properties for oxygen, nitrogen, hydrogen and carbon dioxide. Its oxygen barrier performance is better than that of PVDC coated film and EVOH five-layer co-extruded film. Its oxygen barrier performance is the best among various resin films, comparable to aluminum foil, glass, aluminum oxide-plated film and silicon oxide-plated film.   The production cost of PVA coated composite film is much lower than that of paper-aluminum-plastic composite and aluminum-plastic composite packaging materials, much lower than that of EVOH five-layer co-extruded film, and lower than that of composite film with PVDC coating.   Satisfactory results can be achieved by using the existing dry laminating machines, coating machines, wet laminating machines, extrusion laminating machines and other equipment of various flexible packaging manufacturers. The modified PVA glue does not form a skin, and the viscosity does not increase significantly during normal use. The coating layer is very thin, but the thickness uniformity of the coating remains excellent.   The structural components of polyvinyl alcohol (PVA) high barrier water-based coating liquid are carbon, oxygen, hydrogen and silicon. It is degradable and recyclable. When burned, it only produces carbon dioxide and water without producing other substances harmful to the environment and human health. It is pollution-free and is an ideal environmentally friendly high barrier packaging material.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com ElephChem Holding Limited, professional market expert in Polyvinyl Alcohol(PVA) and Vinyl Acetate–ethylene Copolymer Emulsion(VAE) with strong recognition and excellent plant facilities of international standards.  

Vinyl acetate-ethylene copolymer (VAE) emulsion is the abbreviation of vinyl acetate-ethylene copolymer emulsion. It is a polymer emulsion formed by copolymerizing vinyl acetate and ethylene monomers with other auxiliary materials through emulsion polymerization.   White latex is a water-soluble adhesive, a thermoplastic adhesive produced by polymerization of vinyl acetate monomer under the action of an initiator. Usually called white latex or PVAC emulsion for short, the chemical name is polyvinyl acetate adhesive, which is synthesized from acetic acid and ethylene to vinyl acetate, with the addition of titanium dioxide (low-grade ones add light calcium, talc, and other powders). It is then made by emulsion polymerization. A thick milky white liquid.   VAE emulsion has the advantages of permanent softness, water resistance, low temperature resistance, fast bonding speed, high bonding strength, and is safe and non-toxic. VAE emulsion is widely used in adhesives, exterior wall insulation, building waterproofing, coatings, composite packaging materials, building cement mortar modification, non-woven fabric manufacturing, paper coating and general adhesive for various polar and non-polar materials. Access and other fields.   The characteristics of white latex include normal temperature curing, fast curing, high bonding strength, good toughness and durability of the bonding layer and not easy to age. White latex is a widely used water-soluble adhesive. It is mainly used in wood bonding, construction industry, coatings, etc. It is also used in furniture assembly, surface repair, etc.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com ElephChem Holding Limited, professional market expert in Polyvinyl Alcohol(PVA) and Vinyl Acetate–ethylene Copolymer Emulsion(VAE) with strong recognition and excellent plant facilities of international standards.

Modification of inorganic cementitious materials such as cement with polymer emulsion has been widely used. Since the water in the emulsion will immediately react with the cement after mixing the two and finally solidify, a two-component form is used in most cases. , measure and mix each component in proportion at the construction site. This brings inconvenience to the storage, transportation and construction of materials. The emergence of re-dispersible emulsion powder has changed the above phenomenon. Redispersible latex powder is a micron-sized thermoplastic resin powder obtained by spray-drying a polymer emulsion to remove water. It can be reduced to an emulsion after adding water.Due to this characteristic, it is widely used in single-component JS waterproof coatings, polystyrene board bonding mortars for building insulation, flexible surface protection mortars, polystyrene particle insulation coatings, ceramic tile adhesives, self-leveling mortars, dry-mix mortars, etc. It is widely used in fields that require modification of inorganic cementitious materials.   RDP is a polymer powder produced by spray drying of polymer emulsion. Polymer emulsions are mostly oil-in-water systems in which thermoplastic polymers with a solid content of about 50% are evenly distributed in water with fine particles (0.1-10 μm). After losing water, the polymer particles first form dense spheres and accumulate on the surface. Under the action of energy, discrete polymer particles form a continuous polymer body. To produce redispersible latex powder by the spray drying method, a layer of PVA protective film is added to the surface of the polymer in advance. Due to the existence of the protective film, the dry powders cannot merge. In order to prevent the rubber powder from agglomerating, some fine mineral powders are also added. , such as clay, etc. However, when redispersible latex powder is mixed with alkaline substances such as cement and water, the PVA will be saponified and adsorbed by the quartz in the sand and removed. The rubber powder that has lost its protective film can eventually form a continuous water-insoluble polymer. membrane.   The particle size of the rubber powder (5-250 μm) is much larger than the particle size of the polymer dispersed phase in the emulsion (0.1-10 μm), indicating that the latex particles will agglomerate during the spray drying process. In order to reduce the tendency of polymer powder to agglomerate during long-term storage, inert fluid materials such as clay, talc, silica and other fine particles are usually added to the dry powder as anti-stick fillers. The filler is determined according to the type of polymer and its glass transition temperature. The dosage is generally 8%-30% of the dry polymer powder, which is the main source of ash in redispersible latex powder. After redispersible latex powder is redispersed, the diameter of the latex particles becomes about (0.1-10μm).   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com ElephChem Holding Limited, professional market expert in Polyvinyl Alcohol(PVA) and Vinyl Acetate–ethylene Copolymer Emulsion(VAE) with strong recognition and excellent plant facilities of international standards.

Polyvinyl alcohol, an organic polymer. The molecular formula of polyvinyl alcohol is (C₂H₄O), the degree of polymerization is usually 500 to 5000, and the molecular weight is usually 25000 to 300000. Polyvinyl alcohol at room temperature is a colorless, white or milky white amorphous powder, odorless and tasteless, but it decomposes Can produce irritating smoke and dust.   The physical properties of polyvinyl alcohol change with the degree of polymerization and alcoholysis. Generally, the density range is 1.19-1.31g/cm³, the melting point is 212-267°C, and the boiling point under standard atmospheric pressure is about 340°C. Polyvinyl alcohol is soluble in hot water, insoluble in gasoline, benzyl alcohol ketone and other general organic solvents, soluble in hot hydroxyl organic solvents (such as glycol, glycerin, phenol, etc.), and soluble in liquid at room temperature. Ammonia and dimethyl sulfoxide.   The chemical structure of polyvinyl alcohol is stable, but alcohol-related reactions can also occur based on its molecular structure. For example, polyvinyl alcohol can undergo esterification reactions with inorganic complexes and organic compounds, and acetalization reactions with various aldehydes.   Polyvinyl alcohol is produced differently from other polymers and cannot rely on the polymerization of single unit precursor monomers. Industrially, polyvinyl acetate is usually produced by polymerizing vinyl acetate, and then polyvinyl alcohol is produced by alcoholysis under alkaline conditions.   Polyvinyl alcohol has unique properties such as strong adhesion, film flexibility and smoothness, and is widely used in fiber manufacturing(0588, 1788, 2099, 2499, 2699), papermaking(2099, 1799), textile(1788, 2488, 2299), construction(0588, 1788, 2088, 2488), film or sponge(1788, 1799, 2088, 2099) and binder(0588, 1788, 2088, 2488),etc. many other fields.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com ElephChem Holding Limited, professional market expert in Polyvinyl Alcohol(PVA) and Vinyl Acetate–ethylene Copolymer Emulsion(VAE) with strong recognition and excellent plant facilities of international standards.

High-strength and high-modulus polyvinyl alcohol fiber, as a high-performance fiber product with excellent mechanical properties, biocompatibility and non-toxicity, has shown strong development momentum in the Chinese market in recent years. And driven by factors such as technological innovation, growing market demand, and increasing environmental awareness, the industry will continue to maintain rapid development.   The raw materials of high-strength and high-modulus PVA mainly include basic chemical raw materials such as coal, acetic acid, and vinyl acetate. These raw materials undergo a series of chemical reactions and are converted into preliminary products of polyvinyl alcohol (PVA), providing basic materials for the production of high-strength and high-modulus PVA.   The company uses upstream raw materials and uses specific spinning processes and drawing technologies to produce PVA fibers with excellent properties such as high strength and high modulus. This process requires advanced production equipment and technical support to ensure product quality and stability.   High-strength and high-modulus PVA fibers are widely used in many downstream industries, including building reinforcement materials, composite materials, textile industry (such as bulletproof vests, high-strength ropes, etc.), medical fields (such as surgical sutures, drug sustained-release carriers, etc.) and Environmental protection fields (such as water treatment, soil improvement, etc.). The needs and changes in the downstream market directly drive the development of the high-strength and high-module PVA industry.   The application of high-strength and high-modulus PVA fiber in the field of building materials is particularly prominent. It is mainly used to replace asbestos to enhance the strength and anti-cracking properties of cement products. Simply adding 0.3% to 0.5% of high-strength and high-modulus polyvinyl alcohol fiber and a small amount of polymer to substrates such as cement and gypsum can effectively change the brittleness of the substrate and eliminate cracks.   In textile, papermaking, coating and other fields, high-strength and high-modulus PVA fiber also plays an important role. In the field of textiles, it can be used as an auxiliary agent such as spinning fluid and textile slurry; in the field of papermaking, it is often used for surface coating, adhesion and paper strength improvement; in the field of coatings, it can enhance the adhesion of coatings and durability.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com ElephChem Holding Limited, professional market expert in Polyvinyl Alcohol(PVA) and Vinyl Acetate–ethylene Copolymer Emulsion(VAE) with strong recognition and excellent plant facilities of international standards.

High degree of polymerization PVA has excellent strength and durability due to its high degree of polymerization, and is an important raw material for preparing high-strength materials. High degree of polymerization is generally above 5000.   1. High-strength adhesive: High-polymerized PVA can be used to prepare high-strength glues that can firmly bond various materials and are widely used in construction, automobiles, electronics and other fields. For example, in the construction field, PVA adhesives are used to bond ceramic tiles, stone, wood and other materials, showing good durability and water resistance.   2. Film materials: High-polymerization PVA can also prepare transparent film materials. These film materials have excellent tensile strength, crack resistance and air barrier properties, and are suitable for textiles, food packaging and other fields. For example, film materials made of high-polymerized PVA are widely used in the packaging of high-end textiles because they are non-static, oil-resistant, and resistant to organic chemicals.   3. Special functional materials: Due to its unique properties, ultra-high molecular PVA is often used to prepare materials with special functions. For example, in the field of biomedicine, ultra-high molecular PVA can be used as artificial blood vessels, biomedical materials, etc. Because of its good biocompatibility and mechanical properties, it can effectively replace or assist human tissue.   4. Advanced coating materials: Ultra-high molecular PVA can also be used to prepare advanced coating materials. These materials have excellent wear resistance, scratch resistance, chemical corrosion resistance and other properties, and are widely used on the surfaces of key components in automobiles, aerospace and other fields. coating.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com ElephChem Holding Limited, professional market expert in Polyvinyl Alcohol(PVA) and Vinyl Acetate–ethylene Copolymer Emulsion(VAE) with strong recognition and excellent plant facilities of international standards.  

Low degree of polymerization PVA has good water solubility and plasticity due to its lower degree of polymerization and shorter molecular chain. These properties make low-polymerization PVA widely used in many fields. The degree of polymerization of PVA is generally below 1000.   1. Water-soluble adhesive: Low-polymerized PVA is often used as a water-soluble adhesive because of its excellent water solubility. For example, in the paper products industry, low-polymerized PVA is used for cardboard lamination, corrugated cardboard bonding, and office glue. It also has the advantage of being safe and non-toxic, making it widely used in the packaging industry, such as the bonding of kraft paper bags for heavy objects such as cement, fertilizers, and grain.   2. Coatings and coating materials: Low-polymer PVA can be used as a coating material on the surface of paper, which can significantly improve the gloss and anti-permeability of the paper. In addition, it can also be used as a pigment processing agent to improve the whiteness and gloss of coated paper and enhance the printing effect.   3. Commonly used low-polymerization polyvinyl alcohols such as PVA 05-88. This grade of PVA is also used for medical devices, warp sizing, release agents, etc.   Medium degree of polymerization PVA has a moderate degree of polymerization and exhibits good strength and heat resistance, so it is suitable for occasions that require a certain degree of strength and durability. The degree of polymerization of PVA is between 1000 and 5000.   1. Textile enhancer: Medium-polymerized PVA is commonly used as a textile enhancer in the textile industry. By adding it to textiles, it can significantly improve the softness and wear resistance of textiles, thereby extending their service life. For example, by blending medium-polymerized PVA with cotton, wool, viscose fiber, etc., you can produce Vinyl textiles with excellent properties.   2. Fiber products: Medium-polymerized PVA can also be used as a raw material for fiber products, such as PVA fiber (vinylon) that has been dissolved, spun and acetalized, and is widely used in clothing, tarpaulins, cords, fishing net ropes, etc.   3. Commonly used polyvinyl alcohols with medium polymerization degrees include PVA 17-88, 20-88, 24-88, 26-88 etc. These can also be used to produce glues, paper adhesives, fabric finishing agents, PVA films, etc     Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com ElephChem Holding Limited, professional market expert in Polyvinyl Alcohol(PVA) and Vinyl Acetate–ethylene Copolymer Emulsion(VAE) with strong recognition and excellent plant facilities of international standards.

Polyvinyl alcohol is obtained through the alcoholysis of polyvinyl acetate. Its degree of alcoholysis refers to the percentage of the number of vinyl alcohol units in the molecular chain to the total number of molecular structural units. The degree of polymerization of polyvinyl alcohol refers to the number of repeating units in the molecular chain, which directly affects the length and physical properties of the molecule. The different degrees of polymerization determine the different application fields and properties of polyvinyl alcohol. For example, polyvinyl alcohol with an ultra-high degree of polymerization is often used in applications requiring greater strength and durability, while polyvinyl alcohol with a lower degree of polymerization may be more suitable for applications requiring better solubility or flexibility.   For example: According to the chemical formula of polyvinyl alcohol (-C2H2O-)n, PVA 2488, -88 means that the degree of alcoholysis is 88mol%, and 24- means that its degree of polymerization is about 2400, so the ideal molecular formula of PVA2488 should be (-C2H2O-) 2400. The adjustment is approximately 2400*44=105600. Therefore, one is to measure the size of the formed skeleton, and the other is to measure the conversion rate into the desired product. Those two are different.     Polyvinyl alcohol (PVA) is the hydrolyzate of polyvinyl acetate. The solvent of PVA is water, but its solubility in water is largely affected by the degree of polymerization and is dominated by the degree of alcoholysis. Completely alcoholylated PVA has very little dissolution in water. When the alcoholysis degree is below 88%, it is almost completely dissolved at room temperature of 20°C. However, as the alcoholysis degree increases, the solubility decreases significantly. Solubility PVA is soluble in water. The higher the water temperature, the greater the solubility, but it is almost insoluble in organic solvents.   PVA solubility changes with the degree of alcoholysis and polymerization. .Partial alcoholysis and low polymerization degree PVA dissolve very quickly, while complete alcoholysis and high polymerization degree PVA dissolve slowly. As a general rule, the degree of alcoholysis has a greater impact on the solubility of PVA than the degree of polymerization.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com ElephChem Holding Limited, professional market expert in Polyvinyl Alcohol(PVA) and Vinyl Acetate–ethylene Copolymer Emulsion(VAE) with strong recognition and excellent plant facilities of international standards.