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Ethylene-vinyl acetate copolymer, EVA for short. General vinyl acetate (VA) content in 5%-40%, compared with polyethylene PE, EVA due to the introduction of vinyl acetate monomer in the molecular chain, thereby reducing the high degree of crystallization, improve toughness, impact resistance, filler phase compatibility and thermal sealing performance, is widely used in foam footwear, functional shed film, packaging mold, hot melt adhesive, wire and cable and toys and other fields.   EVA products with 5% to 10% ethylene acetate content are elastic films. EVA with ethylene acetate content of 20~28% is mainly used for hot melt adhesives and coating products; Ethylene acetate content in 5%~45%, the main products for film (including agricultural film) and sheet, injection molding, molding products, foam products, hot melt adhesives.   1. Foam shoe material. Shoe material is the most important application field of EVA resin in China. In the EVA resin used in shoe materials, the vinyl acetate content is generally 15% to 22%. Because EVA resin blended foam products have soft, elastic, chemical corrosion resistance and other properties, it is widely used in the middle and high grade travel shoes, hiking shoes, slippers, sandals soles and interior materials. In addition, this material is also used in the field of sound insulation boards, gymnastics MATS and seals.   2. Film. The main use of EVA film is the production of functional shed film. Functional shed film has high weather resistance, anti-fogging and insulation properties, because polyethylene does not have polarity, even if a certain amount of anti-fogging agent is added, its anti-fogging performance can only be maintained for about 2 months; The addition of a certain amount of EVA resin made of the shed film, not only has a higher light transmittivity, and anti-fogging performance is also greatly improved, generally more than 4 months. In addition, EVA can also be used to produce packaging film, medical film, laminated film, casting film and so on.   3. Wire and cable. With the continuous development of computer and network engineering, more and more people use halogen-free flame retardant cables and silane cross-linked cables for the safety of computer rooms. Because EVA resin has good packing tolerance and crosslinking, it is used more in halogen-free flame retardant cables, semiconductor shielded cables and two-step silane crosslinked cables. In addition, EVA resin is also used to make some special cable sheathing. EVA resin used in wire and cable, vinyl acetate content is generally 12% to 24%.   4. EVA resin also has more applications in toys, such as children's wheels, seat cushions, etc.   5. Hot melt glue. Hot melt adhesive with EVA resin as the main component, because it does not contain solvents, does not pollute the environment and has high safety, it is very suitable for automated production line, so it is widely used in wireless book binding, furniture edge sealing, automobile and household appliances assembly, shoe making, carpet coating and metal anti-corrosion coating.   6. EVA resin is also widely used in ink, luggage, bottle cushion cover and other fields, and it is estimated that EVA resin consumption in these aspects is not less than 15 kt.   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.

When the content of vinyl acetate in EVA is less than 20%, it can be used as a plastic. EVA has good low temperature resistance, its thermal decomposition temperature is low, about 230℃, with the increase of molecular weight, the softening point of EVA rises, the machinability and the surface gloss of plastic parts decline, but the strength increases, the impact toughness and environmental stress cracking resistance improve, EVA chemical resistance, oil resistance compared with PE (polyethylene), PVC (polyvinyl chloride) is slightly worse, and the change is more obvious with the increase of vinyl acetate content. EVA compared to PE performance improvement, mainly elasticity, flexibility, gloss, permeability and other aspects, in addition, its resistance to environmental stress cracking has been improved, the receptivity of the filler increases, can be used to add more reinforcement filler method to avoid or reduce EVA mechanical properties than PE decline. EVA can also be modified to get new applications, and its modification can be mainly considered from two aspects: first, EVA is used as the backbone of other monomer grafting; The second is the partial alcoholysis of EVA.   The forming method of ethylene-vinyl acetate copolymer can use the forming method and equipment of general thermoplastics, and the processing temperature is 20 ~ 30℃ lower than LDPE.Because of its elasticity, it can be made into rubber-like film products without having to go through vulcanization and other processes. The ethylene-vinyl acetate copolymer is easy to color, and the products are colorful. The lower limit of the molding temperature is to maintain a certain fluidity, and the upper limit is to prevent the thermal decomposition of the ethylene-vinyl acetate copolymer. The material temperature is generally controlled at 170 ~ 200℃.The vacuum formed products of ethylene-vinyl acetate copolymer are smooth and transparent. The molding equipment used is similar to LPPE. Similar to the equipment used in PE and PVC, it can be calendered, extruded, and multi-layer co-extruded composite.When extrusion blow molding, the cooling of the material must be given special consideration, and the traction should also be lighter, otherwise the opening is poor, and the slippery agent should be added if necessary.The expansion rate can be controlled effectively by adjusting the amount of foaming agent. The scraps can be recycled and no vulcanization is required. Ethylene-vinyl acetate copolymer foam has the characteristics of good elasticity, light weight, toughness and low shrinkage.   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.

There are differences between polyvinyl alcohol(PVA) fiber and polyester fiber in chemical structure, physical properties and application fields.   First, the chemical structure of polyvinyl alcohol fiber and polyester fiber is different PVA fiber contains a large number of hydroxyl (-OH) functional groups in its molecular structure, so it has good hydrophilicity and solubility. In the molecular structure of polyester fiber, it mainly contains ester group (-COO-) function group, so it has good water resistance and durability.   Second, the physical properties of PVA fiber and polyester fiber are differentThe tensile strength and modulus of polyvinyl alcohol fiber are low, but it has better softness and bending property. Polyester fibers have higher strength and modulus, but are relatively hard and easy to break. In terms of heat resistance, polyester fiber shows good performance and can withstand high temperature processing; The polyvinyl alcohol fiber is easy to melt and decompose at high temperatures.   Third, the application fields of polyvinyl alcohol fiber and polyester fiber are different Due to the different characteristics of polyvinyl alcohol fiber and polyester fiber, they have their own application advantages in different fields. Polyvinyl alcohol fiber is often used in textile, paper processing, plastic film and other fields, and can also be made into waterproof, moisture-proof, anti-static and other functional fibers. The polyester fiber is often used in the production of clothing, fabrics, ropes and other products with high strength and wear resistance, and is also often used in the production of various plastic products.   In short, there are significant differences between polyvinyl alcohol fiber and polyester fiber in their respective chemical structures, physical properties and application fields. Therefore, in actual production and application, product designers and producers need to choose suitable materials according to different needs.   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 2488(PVA 088-50) is a white small granular, stable and non-toxic water soluble polymer, mainly used as building mortar additive and dry mortar field.   PVA 2488 is especially suitable as a mortar additive, which can be used with cellulose ether water retaining agent to improve the flexibility and water retention of cement mortar and gypsum building materials, and improve the viscosity of mortar. In addition, it can also reduce the friction of the mortar, thereby enhancing the working efficiency and quality, preventing the cracking and falling off of the plaster layer, and increasing its adhesion strength and smoothness. The bonding strength of PVA powder is 2.5-3 times higher than that of redispersible emulsion powder, and the service life is long, which can greatly reduce the production cost.   PVA 2488 in ash calcium base putty can significantly improve the cohesion strength, adhesion and water resistance of putty coating. At the same time, it can also significantly improve the phenomenon of delamination scars during grinding, and improve the surface fineness of the putty after grinding. In addition, PVA powder can also accelerate cement solidification in cement-based putty, and has excellent film forming property.   PVA 2488 is one of the main binders of instant glue powder, which can be combined with an appropriate amount of hydroxypropyl methyl cellulose and supplemented with an appropriate amount of thickening and complexing additives to obtain environmentally friendly and high bonding strength double fly powder. At the same time, the product can also be mixed with cement gypsum for wet wall leveling.   The amount of PVA 2488 can be adjusted according to the specific use situation. In gray calcium base putty, the recommended addition amount is 0.3%-0.8%. The amount used in building mortar is also minimal. One ton of gouache in instant glue powder only needs to add 1 kilogram of PVA 2488.   PVA 2488 also has a variety of other uses, such as cosmetics, screen sensitive film, coated paper coating agent, zinc plate printing sensitive film, long fiber yarn sizing agent.   ElephChem Holding Limited, professional market expert in Polyvinyl Alcohol, can provide you with quality products and services. Welcome to inquire, please click the URL or email below: Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com

The average molecular weight of polyvinyl alcohol used as raw material for polyvinyl alcohol fiber is 60000 ~ 150000, the thermal decomposition temperature is 200~220 ℃, and the melting point is 225~230 ℃. Polyvinyl alcohol fiber can be prepared by wet spinning and dry spinning.   Polyvinyl formaldehyde fiber can be obtained by the acetal treatment of the heat treated polyvinyl alcohol fiber. The process of acetalization is the process of washing the strands to remove sodium sulfate, passing through the aldehyde solution, and then washing. The tow can also be cut into short fibers and transported by air to the aftertreatment machine for acetal treatment on the stainless steel net.   In order to improve the fiber properties, the polyvinyl alcohol solution containing the crosslinking agent boric acid (the concentration is 16%) can be wet-spun, and the resulting primary fiber is solidified in the alkaline coagulation bath, and after neutralization, washing and multi-stage high tensile and heat treatment, the strength of 106 ~ 115cN/dtex filament can be obtained.   PVA fibers are used in the industrial field to make canvas, tarps, filter cloth, transport belts, packaging materials, work clothes, fishing nets and cables for Marine operations. High strength, high modulus filament can be used as a transport belt skeleton material, a variety of rubber hose, rubber cloth and rubber shoes lining material, can also make bicycle tire cord.   Because this fiber can resist the alkalinity of cement, and has good adhesion and affinity with cement, it can replace asbestos as the reinforcing material of cement products. It can be blended with cotton to make a variety of clothing and indoor goods, and can also produce knitwear. However, the heat resistance is poor, the fabric is not crisp, and can not be washed in hot water. In addition, it is also useful in non-woven fabrics and papermaking.   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 fiber (referred to as PVA fiber) is a kind of synthetic fiber which is processed by using specific advanced technology and is made of high-quality polyvinyl alcohol (PVA) with high polymerization degree as raw material.   The main characteristics of polyvinyl alcohol fiber are high strength, high modulus, low elongation, wear resistance, acid and alkali resistance, good weather resistance, and cement, gypsum and other substrates have good affinity and combination, and non-toxic, pollution-free, does not damage the human skin, harmless to the human body, is one of the new generation of high-tech green building materials. Polyvinyl alcohol (PVA), the raw material for the production of Vitellin fiber, is a water-soluble polymer with properties between plastics and rubber and is widely used. China's PVA production capacity and output rank first in the world, followed by Japan, the United Kingdom and North Korea.   Polyvinyl alcohol fiber can be produced by wet spinning and dry spinning, the average molecular weight of the raw material polyvinyl alcohol is 60000 ~ 150000, the thermal decomposition temperature is 200 ~ 220℃, and the melting point is 225 ~ 230℃. After heat treatment, the polyvinyl alcohol fiber was acetalized to obtain polyvinyl formaldehyde fiber. It is called Vinylon in the world.   The polyvinyl alcohol fiber can be blended with other fibers, and then dissolved after textile processing to obtain fine yarn high-grade textiles, and can also be made without twist yarn or weft free blankets. It can also be used as an adhesive for paper making to improve the strength and toughness of paper. In addition, it can also make special purpose overalls, surgical sutures, 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 a strong hydrophilic and active organic compound that is commonly used as a binder in paper and printed matter. Polyvinyl alcohol has excellent plasticity and fluidity, and can be used for the coating and packaging of printed matter. Due to its excellent physical and chemical properties, polyvinyl alcohol has been widely used in colorful printing. And provides a variety of roles in colorful printing.   1. Fix the paint Pva can be used as a paint to fix colored pigments and prevent them from spreading on the paper. At the time of printing, PVA can be mixed with pigments to form a pigment paste, which is then printed directly on paper by a printing press. This printing method can ensure the accuracy and consistency of the color. At the same time, through the adsorption of polyvinyl alcohol and paper, the pigment can be firmly attached to the paper and is not easy to fall off.   2. Enhance the toughness and brightness of printed matter In colorful printing, polyvinyl alcohol can also be used as a coating, which can greatly enhance the toughness and brightness of the print. Through the coating treatment of PVA, the printed matter can better resist the influence of external factors such as water and wiping. In addition, the coating of PVA can make the print more beautiful and increase the decorative effect of the print.   3. Other advantages Pva has other advantages. First of all, polyvinyl alcohol is non-toxic, tasteless, safe for human body, and can be used with confidence. Secondly, polyvinyl alcohol can remain stable in a high temperature and high humidity environment, and will not lose its physical and chemical properties due to environmental changes. Finally, the price of polyvinyl alcohol is relatively low, and the use cost is low.   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 088-20 & PVA 1788 PVA 100-27 & PVA 1799 PVA 088-50 & PVA 2488

Polyvinyl alcohol (PVA) is a commonly used additive in the ceramic production process. It mainly plays the role of a binder during the calcination of ceramic bodies. Specifically, PVA can form a polymer bonding structure, which can improve the strength of the ceramic molded body and reduce cracks and deformation during the preparation process. In addition, PVA can also prevent the surface of the ceramic body from drying out and warping during the heating process, as well as prevent problems such as thermal shock and thermal stress.   The quality and usage of PVA have a decisive influence on the quality and performance of ceramic bodies. Excessive addition of PVA may lead to an increase in pores in ceramic products and a decrease in the mechanical strength of ceramic molded bodies.   The calcination temperature has a great influence on the volatilization rate and thermal decomposition of polyvinyl alcohol. Therefore, when controlling the calcination process, the thermal stability of PVA needs to be considered to avoid excessively high or low temperatures causing thermal decomposition of PVA to produce gas, which will affect the performance of the ceramic body. Since the firing process of ceramic products is relatively complex, with a wide range of firing temperatures and long temperature rise and fall times, it is necessary to accurately control the use of PVA during the preparation and firing process of ceramic products to avoid damage to the performance and quality of ceramic products. Negative impact.   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 functions of polyvinyl alcohol in putty mainly include: 1. Improve the initial viscosity of the mortar putty and reinforce the tensile strength in the later stage, making it easy and labor-saving to apply and scrape during the construction process, and it will not crack after drying, thereby improving work efficiency. 2. Significantly improve the cohesive strength, adhesion and water resistance of the putty coating, reduce the amount of gray calcium powder, and improve the surface fineness after polishing of the putty. 3. In polishing putty, polyvinyl alcohol can improve the film-forming properties of the surface, making the coating surface denser, harder, brighter, and more resistant to scrubbing. 4. Combined with gypsum powder and retarding technology, polyvinyl alcohol can produce higher-grade gypsum-based home decoration putty powder, making full use of recovered gypsum resources and realizing resource recycling. 5. Polyvinyl alcohol is particularly suitable for use as an additive for construction putty powder. When used in conjunction with methylcellulose ether water-retaining agents, it can improve the flexibility and water retention of putty powder, improve the adhesiveness of putty powder, reduce friction, and improve work quality.   There are two main types of polyvinyl alcohol powder used for mortar putty: PVA 1788 and PVA 2488. In the mortar application field, polyvinyl alcohol powder with a fineness of 80-120 mesh can be used, while in the putty field, uniform powder with a fineness of 120 mesh or more must be used. PVA 2488 has a higher viscosity, but is relatively expensive. PVA 1788 can also meet the needs.   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 a colorless, odorless, non-toxic polymer substance. Because of its good wettability, emulsification, dispersion, stability and other characteristics, it is often used to manufacture high-efficiency surfactants in detergents. Polyvinyl alcohol can effectively remove oil and stains, and can quickly dissolve in water. It is a green and environmentally friendly cleaning agent.   In different washing daily necessities： 1. Clothing cleaning: Polyvinyl alcohol, as the main component in detergent powder and liquid, has an excellent effect on clothing cleaning. After washing, the clothes will not only be completely clean, but also become soft and comfortable. 2. Cleaning tableware and glassware: As a surfactant in detergents, polyvinyl alcohol can quickly dissolve and remove dirt on tableware and glassware, making them clean and shiny. 3. Household cleaning: Polyvinyl alcohol is also often used in household cleaning, such as cleaning floors, cabinets and other surfaces. It can be mixed with other detergents to achieve better cleaning results.   Advantages： 1. PVA can enhance the adhesion and dispersion of detergents, making the cleaning effect more thorough. 2. PVA has stable molecular weight and good anti-pollution properties, which can effectively extend the service life of detergents. 3. PVA is a green and environmentally friendly raw material that has no negative impact on humans and the environment.   In short, polyvinyl alcohol is widely used in detergents. As an efficient surfactant, it can make our lives more convenient and healthier.   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 2488 & PVA 088-50   PVA 1799 & PVA 100-27 PVA 0588 & PVA 088-05  

Polyvinyl alcohol (PVA) is a water-soluble polymer, not to be confused with PVAc or polyvinyl acetate, which is a water-soluble white glue. In 3D printing, polyvinyl alcohol is popular as a support material because it is water-soluble.   For 3D printing, PVA is the most well-known support material used in  dual-extrusion 3D printers. Typically, fused deposition modeling (FDM) machines use the same material to create the prin ted part and any support structures because there is only one extruder. Depending on the location of the support, removing the support can be a tricky job, not to mention the ugly marks  it can leave on the part. Dual extrusion FDM printers, on the other hand, allow the use of different materials for parts and brackets, which is where PVA comes in handy.     The best advantage of PVA filament is that it is water-soluble, and the printed support structure simply needs to be soaked in water for a few hours. This method also prevents any marks from being left on the part and reduces the need for post-processing such as sanding. It's not as simple as it sounds, dual extrusion can be quite tough and requires a lot of calibration to get a high quality 3D print. As a support material, PVA generally works well with PLA filament because it requires similar printing conditions. PLA is a hydrophobic material, which means it does not "like" water, so if a PLA part is printed with a PVA support, only the support will dissolve in the water, leaving the other part in perfect condition.   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 (PVA) is a water-soluble polymer material that is widely used. The hydrogel prepared from it is a gel with water as the medium. It is a polymer network system that can maintain a certain shape and have a series of unique properties. In addition to the properties of general gels, PVA hydrogels also have the advantages of low toxicity, good mechanical properties (high elastic modulus and high mechanical strength), large water absorption and good biocompatibility.   They have a wide range of applications in the biomedical field. application. For example: drug sustained-release carriers and microcapsules; application in wound dressings; artificial organs and tissues; used in orthopedic surgery to repair or replace articular cartilage.   Preparation method of PVA hydrogel Physical cross-linking method: repeated freezing method, partial freezing and dehydration method. Chemical cross-linking method: chemical reagent cross-linking, radiation cross-linking.   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.