KURARAY POVAL

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

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  

Ultrafiltration membranes are super popular for separating different substances. You can find them in areas like oil processing, textiles, biopharmaceuticals, food production, wastewater treatment, and even making drinking water. Scientists are exploring ways to enhance these membranes so they can produce more water without compromising their filtering ability and also reduce pollution. To this end, many scholars are committed to developing new membrane materials and modifying membranes to improve their application effects. There are many methods to modify membrane materials, such as copolymerization, mixing and surface modification. Blending is simple and easy, making it a popular topic in membrane research. That's why many scientists in the field pay attention to it.   Polyvinyl alcohol (PVA 088-08 & PVA 1088)  has good film-forming properties and pollution resistance, and is widely used as a material for preparing hydrophilic membranes.PVA membranes have a tendency to swell and can even dissolve, so they often need some changes, like heat treatment or blending.    To make these membranes, we used materials like polyvinyl alcohol (PVA), cellulose acetate (CA), glacial acetic acid, metal chlorides, and water. We created blended ultrafiltration membranes using a method called phase inversion, adding metal chlorides like sodium chloride (NaCl), potassium chloride (KCl), and barium chloride (BaCl). We checked how the amount of these metal chlorides impacted the performance of the blended membranes.   Our results showed that when the mass fraction of NaCl and KCl doesn't go over 1% in the membrane solution, the modified blended membrane performs well in retaining substances. The pure water flow increases, while energy use stays pretty much the same. But, when the mass fraction goes above 1.5%, the water flow jumps significantly, but the retention rate drops. We found that about 1% is the best amount for the alkali metal chlorides, while for BaCl, around 1.5% works best. Under the same conditions, blending with KCl results in the highest water flow rate. After we changed the PVA-CA blended membrane with NaCl and KCl, it became more water-loving. But when we used BaCl, it got a bit less water-loving.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com  

Polyvinyl Alcohol (PVA) adhesive is a versatile and widely used product in industries. Its unique properties make it an excellent choice for applications such as paints and coatings, paper making, textiles, and more.   PVA (PVA 088-07 & PVA 0888) adhesive has gained popularity in the paints and coatings industry due to its exceptional bonding properties. It provides strong adhesion to various surfaces, including wood, metal, and plastics, making it ideal for both interior and exterior applications. PVA adhesive offers excellent water resistance, flexibility, and durability, ensuring long-lasting results. Its ease of use and low odor make it a preferred choice for professional painters and DIY enthusiasts alike.   The paper making industry relies heavily on PVA adhesive for its superior binding capabilities. PVA adhesive enables the production of high-quality paper products by providing excellent adhesion between fibers. It improves paper strength, enhances printability, and reduces paper breakage during processing. Additionally, PVA offers good water solubility, which is essential for the controlled dissolution of paper in recycling processes.   In the textile industry, PVA adhesive plays a vital role in various applications, such as fabric finishing, laminating, and bonding. PVA adhesive provides a strong bond between different types of fabrics, ensuring secure seams and preventing fraying. It enhances the fabric's overall stability and durability, making it suitable for applications requiring resistance to washing, dry cleaning, and repetitive mechanical stress.   As a water-soluble polymer, PVA offers numerous advantages over other types of adhesives. Its water solubility allows for easy cleanup, reducing the need for harsh chemicals during application and removal. PVA adhesive can be easily diluted to achieve desired viscosity, making it suitable for a wide range of applications. Its non-toxic nature and low environmental impact further contribute to its appeal as a sustainable adhesive option. Polyvinyl Alcohol adhesive stands out as a reliable and versatile choice across various industries. Its exceptional bonding properties, water resistance, flexibility, and ease of use make it a preferred adhesive for paints and coatings, paper making, textiles, and more. Whether it's enhancing the quality of paper products, improving the durability of textiles, or providing a reliable bond in various applications, It continues to be an indispensable tool for industry professionals. Consider incorporating PVA adhesive into your manufacturing processes to benefit from its numerous advantages.   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 film, also known as polyvinyl alcohol film, is a remarkable polymer-based packaging material that offers a multitude of advantages for various industries.PVA film is non-toxic and safe for direct contact with food and pharmaceutical products. It meets regulatory standards for food contact materials and does not compromise the quality or safety of the packaged items. PVA film is also used in specialized industrial applications, such as the packaging of adhesives, dyes, and chemicals, thanks to its excellent moisture resistance and barrier properties.   One of the notable variants of PVA film is the PVA water-soluble film. This film is specially designed to dissolve quickly and completely in water, making it an ideal choice for single-use packaging applications. The PVA water-soluble film provides exceptional convenience and eco-friendliness, especially in industries such as food packaging, detergent packaging, and agricultural applications.   In contrast to the water-soluble grade, PVA insoluble film offers excellent resistance to moisture and provides a robust barrier to protect the packaged contents. This type of film is commonly utilized in applications where moisture resistance is critical, such as electronic components packaging, chemical packaging, and industrial materials packaging.   PVA special film refers to the customized versions of PVA film that are tailored to meet specific requirements of different industries. These films may possess additional functionalities, such as enhanced strength, increased clarity, improved tear resistance, or specific barrier properties. PVA special films find applications in diverse sectors like pharmaceutical packaging, cosmetic packaging, and Marble demoulding industrial applications.   PVA (PVA 098-08 & PVA 1099) film can be manufactured in different thicknesses and sizes to suit various packaging needs. Its compatibility with different substances allows it to be used with a wide range of products, including powders, liquids, and solid items. ElephChem can customize PVA film of various sizes and specifications according to customer requirements, suitable for a variety of products.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com