EXCEVAL AQ-4104

Food and consumer goods packaging is undergoing significant technological upgrades. On the one hand, the market demands longer food shelf life and reduced reliance on preservatives; on the other hand, sustainable development and regulatory compliance are driving the transformation of packaging materials towards recyclability and biodegradability. In this context, the demand for barrier properties in paper and cardboard packaging has increased significantly, especially in terms of oxygen, grease, and mineral oil barrier properties. Traditional plastic films (such as PE and PP) have limited oxygen barrier performance, while multi-layer composite materials, although offering excellent performance, increase the difficulty of recycling and compliance. In contrast, water-based barrier coatings can significantly improve the functionality of the material without significantly altering the paper substrate structure, giving paper packaging performance close to that of high-barrier materials while maintaining good recyclability. Among the many water-based barrier materials, polyvinyl alcohol (PVOH) system coatings have become an important solution for current paper-based packaging barrier technology due to their excellent oxygen and grease barrier properties and mature industrial application base. The KURARAY POVAL (POVAL 6-98), ELVANOL, and EXCEVAL series of products are representative material systems based on PVOH.   1. PVOH Barrier Mechanism and Performance Advantages in Paper Packaging Polyvinyl alcohol is a non-ionic, water-soluble, linear crystalline polymer, whose molecular chains can form a large number of hydrogen bonds. This highly ordered molecular arrangement makes it difficult for oxygen molecules to diffuse, which is the fundamental reason for its excellent oxygen barrier performance. Under suitable coating and drying conditions, the PVOH coating can form a dense and continuous film layer, thereby significantly reducing the oxygen transmission rate (OTR) of the paper substrate material. In addition, the hydrophilic nature of PVOH makes it equally outstanding in blocking grease and mineral oil, which is particularly crucial for the packaging of bread, coffee, baked goods, etc. By coating ordinary starch-based paper with EXCEVAL HR-3010, with a coating weight of only 7 g/m², the OTR (Oxygen Transmission Rate) can be reduced from >2000 mL/m²/d to <1 mL/m²/d (23℃, 50% RH), demonstrating extremely high barrier efficiency.   ♠ Compared to other common barrier materials, PVOH is a leading material in terms of oxygen barrier performance: Polyethylene, Polypropylene: Weak barrier PET, PA6: Medium barrier PVDC: High barrier but with environmental concerns EVOH / PVOH: Extremely high oxygen barrier performance   At the same time, PVOH has been certified by BfR and FDA for food contact regulations, making it safe for use in food packaging systems, which is an important prerequisite for its widespread use in the packaging coating field.   2. PVOH Barrier Coating Product System and Typical Performance Parameters We offer a variety of PVOH product models suitable for paper-based packaging barrier coatings. Different models vary in viscosity, barrier focus, and application suitability, allowing for selection based on actual needs. The following is a performance comparison table: From an application perspective, low-viscosity models (such as EXCEVAL AQ-4104) are more suitable for high-speed coating or low-coating weight systems, while high-viscosity models (such as ELVANOL 71-30) are beneficial for forming thicker, denser barrier layers. The above products are compatible with various common coating processes, such as blade coating, gravure coating, or curtain coating, and have good process compatibility.   In summary, water-based barrier coatings based on PVOH provide a well-balanced solution for paper-based packaging in terms of performance, sustainability, and regulatory compliance, especially suitable for food packaging scenarios sensitive to oxygen and grease.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com

Polyvinyl alcohol (PVA) is a water-soluble synthetic polymer with excellent film-forming properties, surface activity, and strong adhesion to inorganic and cellulosic materials. Global annual PVA production is approximately 1.05 million tons, with Japan producing approximately 300,000 tons. Approximately 14,100 tons of this is used as a paper processing chemical, a surface sizing agent for plain paper, a sizing agent for coated and coated paper, a fluorescent brightener, an inkjet ink absorber, an adhesive for inorganic fillers, and a silicone sealant for release paper.   The paper business faces challenges like using different types of wood pulp and faster, bigger machines for making paper and printing. Because of this, they need better water-soluble polymers with special features. These polymers are important for making fancy specialty papers and papers used in tech. To adapt to these fundamental changes in the papermaking industry, Kuraray Japan has developed and mastered the properties of modified PVA with novel properties. This article will focus on two specialty PVA: the silanol-modified "R-series PVA" and the high-barrier "Exceval PVA" with the introduction of special hydrophobic groups. The two types will be discussed, along with their properties and applications in paper processing additives.   2. PVA Properties and Dissolution Methods Industrially, PVA is produced by polymerizing and then saponifying polyvinyl acetate. Its fundamental properties depend on its degree of polymerization and saponification. Most commercially available PVAs had a degree of polymerization of 200 to 4000 and a degree of saponification of 30% to 99.9% by mole fraction. The main varieties of PVA produced by Kuraray (Kuraray PVA) are shown in Tables 1 and 2.   3. Specialty Kuraray PVA To date, Kuraray has produced a variety of Kuraray PVAs with varying degrees of polymerization and saponification, which are used in a wide range of applications. As demand grows for better PVA and more varied uses, just tweaking the polymerization and saponification degrees isn't enough anymore. So, Kuraray PVA now comes with special groups added to give it extra function.   This article will introduce two types of functionalized PVA: the "R-series PVA," modified with silanol groups, and the "Exceval PVA (Exceval HR-3010)," which incorporates special hydrophobic groups for high barrier properties.   3.1 Silanol-Modified R-series PVA The R-series is a modified PVA with silanol groups. Table 3 lists the quality standards for the R-series products.     3.2 High Barrier Exceval PVA Exceval PVA is a PVA containing special hydrophobic groups. The introduction of hydrophobic groups enhances the crystallinity of the solid polymer, resolving the dilemma of achieving both high water resistance and stable aqueous solution viscosity, which is difficult to achieve with standard PVA. The use of PVA is increasing annually. PVA is usually used as a stabilizer in adhesives that need to resist water. But, when used in food packaging films, PVA doesn't block oxygen well when it's humid. Exceval PVA is also being developed as an improved material. In coated paper applications, Exceval PVA has also been successfully used when higher water resistance than PVA is required.   This article reports on the results of a new application study for Exceval PVA, specifically its use as an oil-resistant agent in food packaging. The product specifications of the Exceval PVA used in this study are shown in Table 4.   Table 5 shows that coating with Exceval PVA RS-2117 achieves air resistance roughly equivalent to that achieved with partially saponified PVA-217, while significantly reducing water absorption. Paper coated with partially saponified PVA exhibits higher air resistance. This is because the highly hydrophobic, partially saponified PVA has a lower surface tension in aqueous solution, inhibiting penetration into the paper. However, partially saponified PVA suffers from a significant reduction in water resistance. While Exceval PVA, modified with a special hydrophobic group, is fully saponified, it still exhibits the same permeability as partially saponified PVA, offering both improved water resistance and air impermeability.   R-series PVA contains highly reactive silanol groups, which improve adhesion to various inorganic materials. Using the R-series in inkjet media reduces the amount of polyvinyl alcohol used as a binder for silica particles, improving print quality. Even without a crosslinker, the R-series provides high water resistance. Exceval PVA is a modified, hydrophobic polyvinyl alcohol that offers excellent water resistance and gas barrier properties under high humidity conditions. The lower air permeability of coated paper provides a higher barrier to oils and greases than fully water-soluble polyvinyl alcohol, a property further enhanced when used with flake minerals. Exceval is now FDA-registered as safe for contact with food, opening doors for its use in food packaging paper.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com

Polyvinyl alcohol (PVA), also known as PVOH, is a versatile polymer that is widely tested in various industries. In the field of packaging, PVA is popular for its unique properties and advantages. Main uses in the packaging industry include PVA packaging film and PVA packaging adhesive   Polyvinyl Alcohol Adhesive, derived from PVA, offers exceptional bonding strength and adhesion properties. This makes it an ideal choice for packaging applications that require secure seals and strong bonds. Whether it's paper-to-paper, film-to-film, or film-to-paper adhesion, PVA adhesive provides reliable and long-lasting performance, ensuring the integrity of the packaged contents. PVA (PVA 098-04 & PVA 0498) is a water-soluble synthetic polymer, which means it easily dissolves in water without leaving any harmful residues. Water-solubility is a valuable feature in packaging solutions, particularly for products such as detergents, agricultural chemicals, and single-use packaging. When exposed to water, PVA-based packaging dissolves, facilitating convenient and eco-friendly disposal methods, and reducing waste accumulation. Polyvinyl Alcohol offers excellent barrier properties when used as a coating or film in packaging materials. It provides an effective barrier against oxygen, moisture, and UV radiation, safeguarding the packaged contents from external factors that could impact their quality or shelf life. PVA coatings are commonly used in food packaging, pharmaceuticals, and electronics, ensuring product stability, freshness, and protection. PVA is a highly versatile polymer, compatible with a wide range of substances and materials. It can be easily blended or combined with other polymers, additives, or fillers to enhance specific properties or meet unique packaging requirements. Whether it's improving mechanical strength, flexibility, or thermal stability, PVA can be tailored to suit diverse packaging applications, offering customized solutions for various industries.   Its adhesive properties, water solubility, and exceptional barrier properties make it a preferred choice in industries that prioritize product integrity, environmentally friendly disposal, and versatile packaging options. Furthermore, the compatibility and customization options provided by PVA ensure its applicability across a wide range of packaging applications. As sustainable practices and consumer demands continue to shape the packaging industry, Polyvinyl Alcohol remains an essential component in meeting these evolving needs efficiently and effectively.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com JiangSu 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.