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EVOH/ethylene-vinylalcohol-copolymerevoh resin is a high-barrier ethylene-vinyl alcohol copolymer, with an oxygen barrier performance 10,000 times higher than that of common PE (polyethylene). Due to its excellent barrier properties, formability, and environmental friendliness, it is widely used in high-end new material fields such as automotive fuel tanks, films, food containers, and underfloor heating pipes. In particular, its application in food packaging allows for extended shelf life and aroma preservation—ranging from months to years—without the need for preservatives. EVOH/evoh-ew-3201 is produced by copolymerizing ethylene and vinyl alcohol, typically with an ethylene content of 25%–45%.     Applications    1.Packaging As a high-barrier material, EVOH is often co-extruded with various resins for packaging: Food & Beverage: Milk, juice, seafood, and other perishable goods (e.g., PE/EVOH/PA/EVOH/PE five-layer vacuum-sealed films used by Chinese seafood exporters). Non-Food: Chemicals, solvents, cosmetics, pharmaceuticals, and electronics.   2. Automotive Fuel Tanks: EVOH blended with HDPE produces lightweight, cost-effective plastic fuel tanks. Structure (multilayer): Outer layer (HDPE) → Recycled layer → Adhesive layer (LLDPE) → Barrier layer (EVOH) → Adhesive layer (LLDPE) → Inner layer (HDPE). Fuel Lines: PA-EVOH composite tubes replace metal pipes, aiding vehicle lightweighting.       3. Medical Selective Permeable Membranes: Sterilized via radiation (e.g., EVOH hollow fibers for dialysis). Artificial Kidneys: Hollow-fiber membranes for blood purification. Drug Delivery: EVOH-coated polymers for controlled-release medications. Biomedical Implants: Blends with corn starch or cellulose acetate for bone substitutes and tissue repair.   4. Construction Heating Pipes: EVOH’s oxygen barrier prevents corrosion in heating systems. Types: 3-layer (external barrier) and 5-layer (internal barrier) pipes, both using EVOH.   5. Other Uses Textiles: Heat-sealing adhesives with superior wash resistance for apparel. Hydrogen Storage: EVOH-modified hydrogen tank liners maintain elasticity and barrier performance even at low temperatures.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com    

In this era of rapid technological advancement, the development and application of new materials have become a crucial driving force for progress. Polyvinyl butyral (PVB)/polyvinyl-butyral-resin, as an exceptional polymer material, demonstrates tremendous potential across various fields. This article provides an in-depth exploration of PVB's chemical properties, production processes, and its extensive applications in modern technology, offering readers a comprehensive understanding of the scientific principles and technological appeal behind this remarkable material. Fundamental Characteristics of Polyvinyl Butyral/pvb-sd-4 Polyvinyl butyral is a thermoplastic resin synthesized through the condensation of polyvinyl alcohol and butyraldehyde. It boasts outstanding features including high transparency, excellent flexibility, and strong weather resistance. PVB films not only serve as interlayers in safety glass manufacturing but also play significant roles in coatings, inks, adhesives, and other applications. Its unique chemical structure endows PVB materials with superior sound insulation and UV radiation protection capabilities.   PVB Production Process Flow 1. Raw material preparation: Polyvinyl alcohol and n-butyraldehyde as primary materials;   2. Condensation reaction: Polyvinyl alcohol is dissolved in hot water with catalyst, followed by gradual addition of butyraldehyde solution to form PVB prepolymer;   3. Dehydration and drying: The obtained PVB prepolymer undergoes dehydration and drying processes;   4. Pelletizing and forming: Finally, the dried PVB powder is processed into desired shapes or specifications through extrusion and pelletizing techniques.   Application Fields of Polyvinyl Butyral 1. Automotive industry: PVB-based safety glass effectively prevents injury from flying shards, widely used in automobile windshields;   2. Construction sector: PVB laminated glass enhances window safety, thermal insulation, and soundproofing, creating more comfortable living environments;   3. Electronics industry: As devices trend toward slim designs, PVB resin is employed in ultra-thin LCD backlight diffuser plates to improve display quality;   4. Packaging and printing: With excellent adhesion and wear resistance, PVB resin is suitable for various packaging coatings and printing inks.   Future Development Trends Ongoing research focuses on optimizing PVB synthesis processes and expanding its applications. Scientists are exploring methods to enhance mechanical properties by adjusting polymer chain lengths, or incorporating nanoparticles into PVB matrices to create composite films with improved barrier properties. Environmental considerations have also made the development of biodegradable PVB a current research priority.   With its outstanding comprehensive performance, polyvinyl butyral is playing an increasingly vital role across multiple industries. As technology advances, we can confidently anticipate that PVB will continue to deliver more surprises and transformations. For technology influencers, keeping abreast of such emerging material developments not only enriches their knowledge base but also enables them to share cutting-edge information with followers, sparking public interest and enthusiasm for technological innovation.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com    

Local yellowing of PVB/polyvinyl-butyral-resin material at the edges of laminated glass is a rare but serious quality defect, characterized by two approximately 5 cm yellowed areas at the edges. With an occurrence rate of nearly 100%, it has led to customer complaints and financial losses. This study identifies the root cause through production process audits, experimental validation, and microscopic testing, proposing an effective solution. Cause AnalysisThe production process of laminated glass includes cutting, edging, lamination, autoclave treatment, packaging, storage, and transportation. On-site investigations revealed that yellowing only occurs at the contact points (about 5 cm wide) with the product rack base. No yellowing was observed immediately after autoclave treatment, but it appeared after packaging and storage. In high-temperature summer conditions, defects formed more quickly (6–24 hours), and both the plastic film and rubber base at the contact points also turned yellow. Initial hypotheses included: Local PVB /pvb-sd-1Aging Due to High Temperature: Tests placing glass on a newly maintained rack (trimmed rubber base and deepened grooves) showed no yellowing after 24 hours, ruling out this possibility. Plastic Film Aging Contaminating PVB: Replacing the film with adhesive tape still resulted in yellowing, indicating the film was not the direct cause. Migration of Yellowing from Rubber Material: Placing glass on a newly maintained rack prevented yellowing, confirming that aged rubber was the key factor. Testing and Mechanism StudyFourier-transform infrared spectroscopy (FTIR) and gas chromatography-mass spectrometry (GC-MS) were used to analyze yellowed PVB and rubber materials. The findings included: FTIR detected no significant differences in PVB or rubber composition. GC-MS identified additional organic functional groups (e.g., benzothiazole, acenaphthylene, fluorene, anthracene) in yellowed PVB, which are rubber additives (e.g., vulcanization accelerators, antioxidant 4010NA). These substances migrated to PVB due to the "blooming" phenomenon of EPDM rubber, causing localized yellowing. High temperatures and pressure accelerated the migration, explaining seasonal variations in defect formation time. Optimization SolutionsThree solutions were proposed based on the analysis: Isolate Blooming Migration: Add an inorganic barrier between the glass and rubber. Regular Maintenance of Rubber Base: Trim aged surfaces periodically. Replace Rubber Material: Use peroxide-cured rubber to minimize blooming.The factory adopted solution (1), reducing the yellowing defect rate to 0% while balancing cost and effectiveness. ConclusionThe root cause of local PVB yellowing was the migration of additives from the EPDM rubber base. The isolation measure effectively resolved the issue. This method can also be applied to control yellowing defects in other interlayer materials (e.g., EVA), providing a reference for similar process challenges.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com    

The shift toward green packaging in the food industry is imperative. Flexible packaging plays an increasingly vital role in the food sector. Packaging must not only be visually appealing but also safe and environmentally friendly, as it comes into direct contact with food. This product is eco-friendly and non-toxic. Compared to PVDC, it contains no solvent residues and emits no harmful gases when incinerated, making it a safer and more sustainable choice. Under the same conditions, its oxygen barrier performance is 50 times higher than that of PVDC, effectively addressing many challenges in the packaging industry. PVOH/pvoh-water-soluble-film-grade-coated film is a novel, eco-friendly, high-barrier packaging material that can replace PVDC in general food packaging applications while also meeting stricter environmental requirements in other packaging fields.   Differences Between PVOH/pvoh-823t High-Barrier Coated Film and K-Film     1. Structure: Self-adhesive, no primer required.        2. Performance:   Eco-friendly & Cost-Efficient: Low coating weight, no organic solvents used, no solvent emissions or residues. Superior Oxygen Barrier: Thinner coating, lower haze, higher transparency, and exceptional oxygen barrier performance. Higher Yield: Increased packaging area (approx. 15% more per roll compared to K-film of the same weight and width), allowing for more packaged products. Recyclability: PVOH-coated film is degradable and recyclable.   In summary, eco-friendly high-barrier PVOH-coated film is an innovative packaging material that fills a domestic market gap. It can replace PVDC in conventional food packaging while also serving industries with stringent environmental demands. Beyond addressing current sustainability challenges, PVOH-coated film also provides an excellent solution for oxygen barrier issues in flexible food packaging. Its introduction is set to replace a significant portion of metallized film packaging in the market. This product resolves long-standing plastic pollution problems in food flexible packaging and will significantly advance the development of eco-friendly high-barrier materials in China.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com    

Polyvinyl butyral (PVB)/polyvinyl-butyral-resin is a condensation product of polyvinyl alcohol (PVAL) and butyraldehyde, appearing as a white powder. It is soluble in alcohols (e.g., methanol, ethanol, butanol), ketones (e.g., butanone, cyclohexanone), chlorinated hydrocarbons (e.g., chloroethane, dichloroethane), and aromatic hydrocarbons (e.g., benzene, toluene, xylene), and is highly soluble in alcohol-benzene mixed solvents. PVB exhibits excellent compatibility with plasticizers such as phthalate and sebacate esters, as well as with nitrocellulose, phenolic resin, and epoxy resin. It possesses high transparency, excellent cold resistance, impact resistance, and UV resistance, along with strong adhesion to metals, glass, wood, ceramics, and fiber products.   PVB is typically manufactured by first dissolving PVAL in water, then adding butyraldehyde and a catalyst (e.g., hydrochloric or sulfuric acid) under stirring, maintaining a reaction temperature of 15–50°C for the acetalization process. The resulting product is washed, centrifuged, and dried to obtain the final product. PVB is primarily used in the production of interlayer films for laminated glass (e.g., safety glass, bulletproof glass), as well as in coatings (e.g., phosphating primers, metal coatings, wood coatings, and vacuum metallization coatings) and adhesives.   Currently, global PVB resin production is concentrated in the United States, Western Europe, and Japan, with the U.S. being the largest producer and consumer. China's PVB industry began in the 1950s but developed slowly until breakthroughs in ceramic decals and vacuum aluminum plating applications during the Seventh Five-Year Plan (1986–1990), which spurred industry growth. The primary use of PVB resin is as a high-viscosity raw material for PVB films, which serve as interlayers in safety glass. Additionally, it is widely used in coatings, adhesives, ceramic decals, and aluminum foil paper.   PVB films are specialized products for manufacturing safety glass and bulletproof glass. Safety glass, made by sandwiching a PVB film between two layers of ordinary glass, offers excellent low-temperature impact strength, flexibility, light transmittance, weather resistance, sound insulation, and UV blocking. When subjected to strong external impact, the PVB film absorbs energy, preventing glass breakage or fragmentation injuries. PVB-laminated safety glass also features high transparency, water resistance, and aging resistance, with usability down to -60°C. It can also replace acrylic as a transparent material. Multi-layer lamination of glass and PVB films enables the production of military-grade bulletproof glass.   PVB contains hydroxyl, acetyl, and aldehyde groups, giving it strong adhesive properties, making it suitable for various adhesives such as glass adhesives, metal adhesives, enameled wire adhesives, heat-seal adhesives, transfer label adhesives, film adhesives, pressure-sensitive adhesives, and others.   With rising living standards, demand for filter-tipped cigarettes has surged. To protect public health, health authorities mandate 100% tipping for premium cigarettes, leading to a sharp increase in tipping paper usage and, consequently, PVB adhesive consumption.   Furthermore, PVB resin can be blended with other resins to enhance bonding performance, creating adhesives for diverse applications, including wood, ceramics, metals, plastics, and leather.   Due to its high bond strength, cold resistance, oil resistance, wear resistance, and corrosion resistance, PVB is widely used in wood coatings, metal coatings, metal primers, metal inks, foil coatings, vacuum metallization coatings, concrete coatings, waterproof coatings, leather coatings, and glossy surface protective coatings.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com  

By the end of 2023, China's annual EVOH consumption will be about 30,000 tons, but more than 90% of it is dependent on imports, mainly from international giants such as Japan Kuraray (Kuraray) and Japan Synthesis Chemical (JSR).     Chuanwei Chemical (a subsidiary of SINOPEC) is currently the closest to the industrialized production of EVOH enterprises, has built an annual output of 12,000 tons of EVOH (including EVOH EW-3201 and EVOH EW-3801) production equipment, and plans to add 24,000 tons of new production capacity in the future, with a total production capacity of 36,000 tons/year, which is expected to be the first enterprise to achieve large-scale production in China. Dalian Institute of Chemical Physics, Chinese Academy of Sciences, has developed an EVOH preparation method based on alkaline deep eutectic solvent, which reduces the separation cost, improves the product purity and provides technical support for the localization of EVOH.   Shenzhen Institute of Advanced Polymer Research has successfully developed EVOH resins with performance comparable to that of international first-class products through continuous polymerization technology and polymer chain segment micro-regulation technology, filling the gaps in domestic technology.   Policy support: the national “14th Five-Year Plan” clearly puts forward to strengthen the independent research and development of high-end polymer materials, EVOH as a high-performance barrier material, by the policy encouragement and industrial funding support.   Market prospect: It is expected that after 2025, with the commissioning of domestic enterprises such as Chuanwei Chemical, the annual production capacity of EVOH in China is expected to exceed 50,000 tons, which will significantly reduce the dependence on imports, and some of the products may even be exported to the international market.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com    

EVOH (Ethylene Vinyl Alcohol Copolymer) is considered to be a more environmentally friendly material, mainly in terms of its advantages in reducing food waste, prolonging product freshness, and in the recycling process.EVOH's gas barrier properties are excellent, and it can effectively prevent oxygen, water vapor, and other substances from entering into the package, thus prolonging the shelf-life of the food, and reducing food spoilage and waste. This feature makes EVOH particularly important in food packaging, and can significantly reduce the environmental burden caused by food expiration or spoilage.     In addition, EVOH has good recyclability, and although its recyclability is not as good as that of materials such as PE (polyethylene) and PP (polypropylene), it can be used in combination with these materials to take advantage of the strengths of both materials; PE and PP have better mechanical strength and chemical resistance, while EVOH provides a better barrier to gases. Through composite use, this multi-layer packaging material ensures packaging functionality while allowing for easier disposal during recycling, helping to reduce resource waste.   What's more, EVOH is produced in a relatively environmentally friendly manner and does not release harmful substances during its use. Compared to other traditional plastic materials, the use of EVOH reduces the need for chemical additives, further minimizing the impact on the environment. Therefore, EVOH is playing an increasingly important role in promoting green packaging and circular economy, becoming an environmentally friendly and sustainable packaging material.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com    

I. Definition of Carboxylated Polyvinyl Alcohol (CPVA)Carboxylated polyvinyl alcohol is a hydrogen-modified polymer obtained through a carboxylation reaction based on polyvinyl alcohol (PVA). CPVA  has typically higher solubility and better performance than unmodified PVA.     II. Functions of Carboxylated Polyvinyl Alcohol PlasticizerCPVA can be used as a plasticizer to improve the processing properties and flexibility of plastics. It is often used in the production of soft plastics, coatings, and rubber products. AdhesiveCPVA can act as an adhesive, forming strong bonds between different materials. For example, when used as glue, it can bond materials such as paper, wood, and plastic together. LubricantCPVA can function as a lubricant, reducing friction on contact surfaces and extending the lifespan of materials. It is commonly used in industrial applications such as metalworking, textile manufacturing, and plastic processing. III. Applications of Carboxylated Polyvinyl Alcohol Packaging MaterialsCPVA is used in manufacturing food packaging materials, such as wrapping paper, plastic films, and straws. This polymer is not only safe and environmentally friendly but also provides excellent flexibility and water resistance, offering effective protection for food packaging. Paper CoatingCPVA is used to coat paper, enhancing its strength and water resistance. It is commonly applied in the production of books, magazines, and other paper-based products. Medical FieldCPVA is used to manufacture medical products, such as sutures and artificial cartilage. It has good biocompatibility and poses no adverse effects when in contact with human tissues, ensuring the safety and reliability of medical materials.   ConclusionCarboxylated polyvinyl alcohol is a multifunctional material with applications as a plasticizer, adhesive, and lubricant. It is widely used in packaging materials, paper coatings, and the medical field.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com  

EVOH (ethylene vinyl acetate copolymer) is a polymer with excellent gas barrier properties and is commonly used in food packaging, medical products, and protective materials for automotive and electronic products. Due to the high molar fraction of vinyl acetate, EVOH exhibits excellent gas barrier properties, especially for oxygen and nitrogen, and is therefore often used in food packaging to extend the shelf life of products.     The gas barrier properties of EVOH stem from its highly crystalline structure, which allows the molecular chains to be arranged more tightly, reducing the path of gas molecules through the material. In order to improve the properties of EVOH, different degrees of hydrolysis are often used to adjust the degree of crystallinity. The higher the degree of hydrolysis, the higher the crystallinity of EVOH and the consequent increase in barrier properties. Therefore, the degree of hydrolysis of EVOH must be strictly controlled during the production process to ensure that the material has ideal gas barrier properties. In China, EVOH products (EW-3201 and EW-3801) produced by Sinopec are highly recognized.     EVOH also offers significant advantages over other plastics in terms of chemical resistance, high temperature resistance and transparency. Its excellent processability allows it to be used directly in multilayer composites without the need for complex post-treatment operations during production, thus enhancing the functionality and economy of the final product.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com      

🔬 At a molar fraction of 5% vinyl acetate, the mechanical properties of EVA (ethylene vinyl acetate copolymers) become very similar to those of soft PVC.EVA is flexible in its own right, which gives it a number of advantages, such as the disadvantage of avoiding the migration of plasticizers, which is the main reason for the gradual replacement of PVC.     💪 These copolymers have a higher modulus and better processing properties than typical elastomers and do not require vulcanization considerations. Polyvinyl alcohol can be obtained by hydrolysis of polyvinyl acetate. Poly(vinyl alcohol) is an atactic cubic polymer but does not disrupt the lattice structure due to the small hydroxyl groups. Therefore, ester bases that are not sufficiently hydrolyzed reduce crystallinity and the number of intermolecular hydrogen bonds.   💧 Highly hydrolyzed poly(vinyl acetate) (containing fewer unhydrolyzed ester groups) has a higher crystallinity. As the degree of hydrolysis increases, the molecules become easily crystallized. If these molecules are not sufficiently dispersed before dissolution, hydrogen bonding will cause them to associate with each other. In order to achieve hydrolysis levels above 98%, manufacturers need to operate at a low temperature of 96°C to ensure that the larger molecules have sufficient thermal energy to dissolve.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com  

PVB resin, a versatile and highly adaptable material, has found its way into a myriad of applications across various industries. Its unique properties, such as transparency, durability, and adhesion, make it an indispensable component in modern manufacturing and technology.   PVB resin is widely used as an interlayer material in the production of safety glass. This type of glass boasts exceptional transparency and high impact resistance, making it ideal for applications in the aerospace and automotive sectors. Whether it’s for airplane windows or car windshields, PVB resin-based safety glass ensures both clarity and durability, providing an extra layer of protection in high-stakes environments.   In the realm of protective coatings, PVB resin plays a crucial role in manufacturing anti-corrosion and anti-rust paints. These coatings are known for their strong adhesion, excellent water resistance, and ability to withstand harsh weather conditions. Additionally, PVB resin is used to create metal primers and cold-resistant paints, ensuring that structures and machinery remain intact and functional even in extreme environments.   PVB resin is a key ingredient in the production of vibrant decorative films, which can serve as an alternative to traditional ceramic decals. These films are not only visually appealing but also highly durable. In the PVB resin industry, it is also used to create molding compounds that can replace metals like steel and lead. Furthermore, PVB resin-based adhesives are widely employed for bonding materials such as wood, ceramics, metals, plastics, leather, and laminated composites, showcasing its versatility.   The textile industry benefits from PVB resin in the form of fabric treatment agents and yarn tubes, which enhance the quality and durability of textiles. In the food industry, PVB resin is used to produce non-toxic packaging materials, ensuring the safety and integrity of food products. Its non-toxic nature makes it an ideal choice for packaging sensitive items like tea and cigarettes, where odor retention is a concern.   In the paper industry, PVB resin is utilized as a paper treatment agent, improving the strength and quality of paper products. Additionally, it is used to create anti-shrinkage agents, stiffening agents, and other waterproof materials, further expanding its utility in industrial applications.   PVB resin’s solubility in alcohols and non-toxic nature make it a preferred choice in the printing industry. It is compatible with various printing techniques, including flexography, gravure, letterpress, screen printing, and heat transfer printing. Its ability to produce odor-free prints makes it suitable for packaging sensitive items like tea and cigarettes. Moreover, its cationic properties allow it to adhere strongly to glass surfaces, making it particularly effective for glass decoration through screen printing.   From enhancing the safety of vehicles and aircraft to revolutionizing the printing and packaging industries, PVB resin has proven to be a material of immense value. Its adaptability, combined with its eco-friendly and non-toxic characteristics, ensures that it will continue to play a pivotal role in shaping the future of technology and industry. As research and innovation progress, we can only expect to see even more groundbreaking applications of this remarkable material.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com

In recent years, with the accelerated pace of urbanization in my country and the continuous growth of automobile sales, there has been a strong demand for PVB laminated glass. At the same time, with the development of technology, PVB Film has been researched and developed, and the application market has been further developed. In this development process, we must not only pay attention to new technological innovation, but also overcome the technical difficulties in the process of PVB waste collection and recycling, so as to achieve the environmental friendliness and maximize the economic benefits of the PVB industry. At present, the recycling of PVB resin mainly includes physical recycling method, chemical recycling method and energy recovery method.   Physical recycling is to put the discarded PVB through a series of physical treatment processes, such as separation, purification, cleaning, etc., and at the same time, add certain additives as required for reuse. This method can effectively utilize PVB materials and greatly reduce environmental pollution. For example, the PVB solid waste and scraps discarded in the market are recycled, and after sorting, cleaning, drying, and crushing processes, plasticizers, tougheners, three-salt stabilizers and other additives are added, and waterproof membranes for construction are produced through high-speed mixing, mastication, tableting and other processes. Through experimental research, it has been found that the waterproof membrane has good mechanical properties, convenient processing, and a wide operating temperature range, and has broad market prospects in the construction field.   The chemical recycling method uses light, heat, radiation, and chemical reagents to degrade PVB polymer into low-molecular single or hydrocarbon substances. At the same time, the cracked raw materials can be reused. Common cracking methods include hydrolysis, alcoholysis, thermal cracking, hydrocracking, catalytic cracking, etc. However, the current technology of this deep chemical recovery method is not very mature, the technology cost is high, and the economic benefits are low. Currently, the most commonly used method is to process waste PVB to obtain pure polymer resins and additives. Supercritical separation technology is used to separate the additives and resin in colorless PVB.   Energy recovery is the process of extracting energy from waste plastic, typically used as fuel or to generate steam to generate electricity. Because PVB polymer contains a large amount of hydrocarbons, it is flammable. Although the energy recovery method is one of the methods for recycling PVB waste, it is not commonly used due to its high cost.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com