GOHSENOL NH-18

Polyvinyl alcohol (PVA) is one of the most important and widely used water-soluble polymers in industrial applications. Its preparation process involves first polymerizing vinyl acetate (VAc) to form polyvinyl acetate (PVAc). The vinyl acetate groups (-OAc) on the PVAc are then converted to hydroxyl groups (-OH) through an alcoholysis (hydrolysis) reaction. Based on the degree of alcoholysis, PVA is divided into two major series: fully hydrolyzed and partially hydrolyzed.     Fully hydrolyzed 99 series PVA (such as ElephChem pva 2699, 2499, 2099, and 1799) refers to grades with a degree of hydrolysis of 99.0 mol% or higher. This extremely high degree of hydrolysis is the core prerequisite for these PVA grades to achieve high performance, strength, and water resistance. This blog will analyze, from four perspectives: molecular structure, grade differentiation, performance advantages, and key application areas, how fully hydrolyzed 99 Series PVA has become the cornerstone of "hardcore" materials such as high-performance fibers, specialty films, and durable adhesives.   1.Molecular Structure Determine Performance: The Mechanism and Effect of Complete Hydrolysis   1.1 Hydroxyl Density and Hydrogen Bonding Network Construction In the fully hydrolyzed 99 Series, nearly all hydrophobic vinyl acetate groups on the molecular chain are replaced by hydrophilic hydroxyl groups. Hydroxyl groups (-OH) are extremely polar functional groups that form strong intramolecular and intermolecular hydrogen bonds, building a highly dense and stable three-dimensional network. This dense hydrogen-bonding network contributes to two crucial molecular effects: High crystallinity: Strong hydrogen bonding forces enable PVA molecular chains to stack neatly and tightly, forming highly ordered crystalline regions. This increased crystallinity is the fundamental reason for the high tensile strength and high modulus of 99 Series PVA. Water Resistance: The dense hydrogen bond network makes it difficult for external water molecules to penetrate the crystals at room temperature and disrupt the connections between the molecular chains, effectively preventing PVA from dissolving. Therefore, 99 series PVA is essentially insoluble in water at room temperature and typically requires hot water above 90°C to fully dissolve and disperse. This ensures its structural stability in humid environments and aqueous systems.   1.2 Linear Correlation between Degree of Polymerization and Viscosity/Strength Assuming a constant degree of hydrolysis (HD>99.0%), the differences between fully hydrolyzed 99 series PVA grades are primarily determined by the average degree of polymerization (DP) or average molecular weight (MW). DP is a key parameter that determines the rheological properties of polymer solutions and the mechanical properties of the final product. The DP ladder of ElephChem 99 series grades (based on the average DP): Ultra-High DP (Polyvinyl Alcohol 2699): DP = 2600-3000. These grades have the longest molecular chains and the highest degree of chain entanglement. Its highest solution viscosity imparts exceptional cohesive strength and adhesion to the cured material, making it an ideal choice for manufacturing high-strength, high-modulus fibers and specialty high-viscosity adhesives. Medium-high degree of polymerization (Polyvinyl Alcohol 2499 / Polyvinyl Alcohol 2099): DP = 2,000-2,500. This grade offers a balanced viscosity and mechanical properties. It is the most widely used grade for sizing agents in the textile industry and for general-purpose, high-performance coatings and films. Medium-low degree of polymerization (Polyvinyl Alcohol 1799): DP = 1,700-1,800. Its relatively low solution viscosity facilitates its use in systems with high solids content or requiring rapid penetration. For example, precursors for polyvinyl butyral (PVB) require precise molecular weight control (e.g., 1799 for PVB, MW = 76,000-82,000) to ensure efficient acetalization and the quality of the resulting interlayer film.   2. Core Performance Advantages of the Fully Hydrolyzed PVA 99 Series Excellent Mechanical Properties (High Strength, High Modulus): High crystallinity gives PVA high tensile strength and modulus. Wet or dry-wet spinning yields high-strength, high-modulus PVA fibers with properties comparable to those of ultra-high-density polyethylene (UHMWPE). These fibers are a key raw material for replacing asbestos in cement reinforcement and ballistic materials. Excellent Gas Barrier Properties: PVA films, particularly those produced from the 99 series, offer one of the best barrier properties against gases like oxygen and nitrogen among known polymer materials. The highly hydrogen-bonded network within their molecular structure prevents gas permeation, making them ideal as high-performance barrier layers for oxygen-sensitive food and pharmaceutical packaging. Chemical and Oil Resistance: The 99 series PVA shows good resistance to solvents, oils, greases, and weak acids and bases because its molecules are very stable and it has few non-crystalline areas. This makes it useful for industrial coatings and special glues.  Thermal stability: High crystallinity gives 99 series PVA a higher glass transition temperature (Tg) and melting temperature (Tm), improving the material's resistance to heat deformation and upper temperature limit.   3. Analysis of Key Industrial Applications of Fully Hydrolyzed 99 Series PVA The unique properties of 99 Series PVA make it irreplaceable in multiple high-value-added sectors:   3.1 High-Strength High-Modulus PVA Fiber (HTHM PVA Fiber) This is one of the most valuable end-products of 99 Series PVA. For example, the 1799 grade, with a DP of approximately 1750, achieves a high degree of molecular orientation through specialized spinning, heat treatment, and stretching processes. Applications: Used to replace asbestos and steel mesh in construction, it reinforces cement, mortar, and concrete, significantly improving the material's impact resistance, freeze-thaw resistance, and fatigue resistance. It is widely used in civil engineering structures such as highways, water conservancy projects, tunnel linings, and cement slabs.   3.2 Textile and Paper Industry Textile Warp Sizing: High-polymerization grades such as 2499 and 2699 provide an extremely tough and smooth size film, significantly improving the abrasion resistance and breaking strength of warp yarns during weaving. They are the preferred size for high-density, high-count fabrics (such as denim and premium cotton). Papermaking Surface Sizing Agent: As a surface sizing agent, the 99 series PVA forms a high-strength film on the surface of paper, significantly improving its surface strength, folding resistance, and printability. This is crucial for high-end coated paper and specialty functional papers (such as thermal paper and dust-free paper).   3.3 Polyvinyl Butyral (PVB) Precursor PVB is a core material for automotive safety glass and architectural laminated glass. As an intermediate in the acetalization reaction, the quality of PVA directly determines the optical clarity, toughness, adhesion, and aging resistance of the final PVB film. Grades: 1799 specialty grades (such as SX-I/II/III) with a DP ≈ 1700-1850 are precisely designed to ensure ideal molecular structure and uniform dispersion during the subsequent acetalization reaction, meeting the stringent optical quality requirements of safety glass.   3.4 High-Performance Building Adhesives and Dry-Mix Mortars In the construction industry, 99-series PVAs are used as high-performance additives to improve material durability and adhesion. Applications: As secondary dispersing binders and water-retaining agents in mortars and putty powders, their high bond strength and water resistance ensure the stability and durability of wall putties, tile adhesives, and other materials in humid and temperature-stable environments.   4. Conclusion: Future Outlook for Fully Hydrolyzed 99-Series PVA 99-series PVAs are a classic and promising branch of polymer materials science. By precisely controlling the degree of hydrolysis and polymerization, as demonstrated by ElephChem's grade system, the industry can develop specialized grades tailored to meet the demands of diverse and demanding applications. From high-strength fibers that reinforce modern infrastructure, to PVB interlayer films that ensure safety, to environmentally friendly, high-performance coatings that enhance quality of life, the 99 series PVA, with its unparalleled strength, stability, and water resistance, continues to play a key role as a driver of high-performance, "hardcore" materials in the upgrading and sustainable development of the global manufacturing industry. As novel uses, like 3D printing and medical hydrogels, ask for better PVA, studies into improving and changing the 99 series PVA will likely increase. This will probably expand its value in industry and its market potential.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com  

1 PVA (PVA 088-20 & PVA 1788) water resistance modification PVA (Polyvinyl alcohol) has very low air permeability and is a high-barrier packaging material with excellent performance. Because the molecular chain contains a large number of hydroxyl groups and has high hydrophilicity, these hydroxyl groups are easy to form hydrogen bonds with water molecules under high humidity, resulting in changes in the aggregate structure of PVA, causing its barrier properties to drop sharply. Therefore, necessary water resistance modification should be carried out on PVA to reduce the effect of humidity on the barrier properties of PVA. The mechanism of PVA water resistance modification is to cross-link PVA by adding a cross-linking agent, and completely or partially block the hydroxyl groups, which can reduce its hydrophilicity and achieve the purpose of improving water resistance. The 8511 Institute of the China Aerospace Corporation has developed a melamine resin modified liquid "868" that has no toxic side effects on the human body. "868" is a multifunctional polycondensate. When the amount added is not large, it can moderately cross-link with the hydroxyl groups in PVA, so that PVA forms a strong three-dimensional structure coating, which determines the air tightness of PVA under wet conditions and improves water resistance. This modified PVA coating liquid will not form a skin at room temperature, will not swell or fall off when in contact with water, and can be used for glue preparation and coating at room temperature.   2 PVA (PVA 100-27 & PVA 1799)water-soluble modification PVA's water solubility can be used to make water-soluble films. Water-soluble films are a new type of green and environmentally friendly packaging material, which is widely used in the packaging of various products in Europe, America, Japan and other countries. For example, pesticides, fertilizers, pigments, detergents, water treatment agents, concrete additives, detergents, chemical reagents for photography and chemical reagents for gardening care. Because the water solubility of pure PVA film cannot meet the requirement of dissolution time ≤ 300s in water at 20℃, Wen Huojiang et al. carried out Michael addition reaction with PVA and acrylamide, and then hydrolyzed and synthesized modified PVA under base catalysis. Water-soluble anionic groups were introduced into the PVA molecular chain to enhance the solubility. Water-soluble films were prepared using this as raw material, and the relationship between the amount of alkali, acrylamide and modification rate was discussed. The modification rate made a great contribution to the low-temperature rapid solubility of the prepared film within a certain range. The effect on water solubility beyond a certain range was not significant, but it would lead to excessively high costs.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com

We used partially alcoholysis PVA-217SB (PVA080-22 & PVA1780) and high-efficiency environmentally friendly pulp together, and added a certain proportion of starch. We conducted experiments on several polyester-cotton varieties, which not only significantly improved the pulp shaft quality, but also greatly reduced the pulp cost.   Pulp performance: The chemical structure of PVA varies depending on the degree of alcoholysis. PVA with an alcoholysis degree of 99.6% is fully alcoholysis, like the PVA-1799 (PVA 100-27) we usually work with. On the other hand, PVA with an alcoholysis degree of 88% is partially alcoholysis, such as PVA-1788 (PVA 088-20) and PVA-217SB. The fully alcoholysis PVA mainly has hydroxyl groups in its structure, whereas the partially alcoholysis version contains some ester groups along with hydroxyl groups. This difference makes their performance quite distinct. For example, when mixing partially hydrolyzed PVA with completely hydrolyzed PVA and starch, the starch ratios needed aren't too different between the two. Generally, it should not exceed 70%, that is, the starch to PVA mixing ratio is generally about 7:3, in order to obtain a slurry with good miscibility. Runli's eco-friendly slurry is a milky white liquid that has over 98% effective ingredients. It has a viscosity of 2 to 8 mPa·s at 20℃ and a pH level between 7.5 and 8.5. This slurry flows well, has good elasticity, strong adhesion, mixes easily with other slurries and additives, and it's simple to remove after use.     Summary: (1) From the trial, tracking, and test analysis of Runli slurry and partially hydrolyzed PVA, we found that the slurry flow rate is stable and it is not easy to form sizing skin at low temperature. The thousandth reel is smooth, the sizing yarn feels smooth, and there is less regenerated hairiness. (2) The new sizing yarn indicators are way better than the old formula. We’ve seen a big drop in loom breakage and a solid increase in the good axis rate and loom efficiency. (3) The use of Runli sizing agent and partially alcoholysis PVA (PVA-217SB) sizing agent has greatly reduced the sizing cost.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com  

Polyvinyl Alcohol (PVA), a versatile synthetic polymer, has gained significant popularity and is in high demand across various industries. It has emerged as a highly sought-after material across a wide range of industries due to its exceptional properties and versatility. Its water-solubility, compatibility with various substrates, barrier properties, safety, biodegradability, and applications in the textile industry make it a preferred choice for manufacturers.     One of the key reasons for the widespread use of Polyvinyl Alcohol is its excellent water-solubility. When dissolved in water, PVA forms a clear, transparent, and flexible film that exhibits strong adhesion to different surfaces. This property makes it invaluable in applications such as paper coatings, adhesives, and textile sizing.   Polyvinyl Alcohol is often preferred due to its compatibility with a wide range of materials. It exhibits excellent adhesion to various substrates such as paper, textiles, metal, wood, and plastics. This versatility allows for its use in multiple industries, including packaging, construction, textiles, and ceramics.   PVA films offer exceptional barrier properties, such as oxygen, moisture, and flavor barrier. This makes them suitable for food packaging applications as they help maintain the freshness and quality of packaged products. Additionally, PVA is considered safe for use in food contact applications, complying with stringent regulatory standards.   In an era where sustainability is a growing concern, Polyvinyl Alcohol stands out as an environmentally friendly option. PVA is biodegradable under specific conditions, making it an attractive choice for applications that require eco-friendly materials. Its non-toxic nature and minimal environmental impact further contribute to its appeal across industries.   Polyvinyl Alcohol (PVA 100-27H & PVA 1799H) is extensively used in the textile industry for fabric sizing. It enhances the strength, elasticity, and durability of textiles, resulting in improved resistance to wear and tear. PVA-based textiles also exhibit excellent dye retention properties, making them suitable for vibrant and lasting color creations.   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), as a water-soluble synthetic polymer, offers excellent adhesive properties, making it an ideal choice for a wide range of applications. One key advantage of PVA is its ability to form a strong bond between different materials, including wood, paper, and fabrics. This attribute makes PVA Adhesive highly suitable for woodworking projects, where a strong and durable bond is required.   For woodworkers, Polyvinyl Alcohol for Woodworking opens up new possibilities. Its water-soluble nature allows for easy application and cleanup, while providing a strong bond between wood surfaces. Whether it's joining pieces of furniture, laminating wooden panels, or creating intricate woodcraft, PVA-based adhesives ensure a reliable and long-lasting bond.   In the paper-making industry, the demand for efficient and high-quality adhesive solutions is crucial. Polyvinyl Alcohol Glue for Paper Making offers excellent performance characteristics, boosting both the efficiency and quality of the production process. When applied as a coating on paper, PVA adhesive ensures improved strength, dimensional stability, and printability. Additionally, it provides excellent resistance to moisture, heat, and chemicals, enhancing the overall durability of paper products.   The versatility of PVA extends to the manufacturing of Polyvinyl Alcohol Film. This transparent, flexible film exhibits excellent adhesive properties, making it an essential component for various industries. From packaging materials to labels, PVA Film ensures secure adhesion while maintaining the integrity and appearance of the product.   Polyvinyl Alcohol (PVA 100-27H & PVA 1799H), with its unique properties, enhances the performance of adhesive products in numerous applications. Whether it's in woodworking, paper making, or other industries, PVA-based adhesives offer strong bonds, improved durability, and ease of use. As a supplier of PVA products, we can provide tailored solutions to meet the specific requirements of your adhesive applications.   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 global consumption structure of polyvinyl alcohol (PVA) is: polymerization assistants account for about 24%, polyvinyl butyral (PVB) accounts for about 15%, adhesives account for about 14%, textile pulp accounts for about 14%, and paper pulp Materials and coatings account for about 10%, and others 23%. The consumption structure of polyvinyl alcohol (PVA) in China is: polymerization assistants account for about 38%, fabric slurries account for about 20%, adhesives account for about 12%, vinylon fibers account for about 11%, papermaking slurries and coatings account for about 8% %, architectural coatings account for about 5%, and others 6%. Polymerization aids, fabric sizing and adhesives are the main downstream consumer markets for polyvinyl alcohol.   In the first half of 2023, the supply and demand of China PVA (PVA 100-27 & PVA 1799) products( were in a weak balance, and prices were running at low levels. The advantages of China PVA variety in supporting a stable market share. With the introduction of new technologies, new processes, and new products, the continuous expansion of new application fields, and the gradual replacement of imported products, new development opportunities have been brought to the domestic polyvinyl alcohol and vinylon industry. However, as various companies increase their export efforts and adopt fierce competition at the low end, and with the adjustment of China's industrial structure, rising wages and other costs, and high environmental protection requirements, some downstream industries, such as the labor-intensive textile industry, have relocated to Southeast Asia, making domestic Demand growth momentum has slowed, foreign consumption has increased, and exports have increased. After more than ten years of competitive integration and optimization, the industry is showing a new pattern of optimized production capacity, increased concentration, stable market varieties, slow growth in market demand, high technical barriers, moderate competition, and innovation-driven development, reaching a new balance between supply and demand. Develop into a benign new business format.   With the rapid development of PVA downstream industries such as PVA optical film, PVB film, polymerization additives, soil improvement, paper adhesives, ceramic adhesives, environmental protection, medicine and cosmetics, the demand for special PVA products is very strong, and Anhui The special PVA products of leading enterprises in the industry represented by ElephChem have developed rapidly, and they have increased their research and development efforts on PVA fiber, PVB resin, PVB film, PVA optical film, redispersible rubber powder and other products. Special varieties of PVA and The production technology of downstream new material products is becoming increasingly mature, filling many gaps in the country. New PVA products are gradually being put on the market, and their market share is also constantly increasing. Common varieties have basically achieved import substitution, and the downstream consumption structure of the domestic PVA industry has been further expanded.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com