Polyvinyl Alcohol(PVA) application

Since the industrial production of PVA, after decades of development, its use has been greatly expanded, from the initial use only for the production of vinylon, to the textile, paper, construction, chemical, electronics and other industries, currently PVA New uses are still being developed and PVA has become an important and essential material. At the same time, PVA, as the “most eco-friendly product”, has also received extensive attention and application in environmental protection and safety. Because PVA has many excellent physical and chemical properties, it has a very wide range of uses in actual production, and has been greatly developed in recent years, and application development in various new fields is in full swing.
(1) Fabric and fabric processing Due to the high adhesion between molecules, PVA has good drawing and film forming properties, and once established the position of PVA as raw material of vinylon fiber. The vinylon fiber made of PVA can be blended with cotton, wool and viscose fiber or purely for the production of clothing and tarpaulins, cords, ropes, etc. It is an ideal substitute for asbestos. The water-soluble fiber developed in recent years has water solubility, acid resistance, alkali resistance, organic solvent resistance, and good salt and chemical resistance. It can be dissolved in different water temperatures as needed, and its waste liquid is activated sludge. After treatment, it is completely degraded and pollution-free. It is an environmentally friendly material with great application prospects and wide use. The water-soluble fiber is mainly used as a raw material for papermaking, a raw material for non-woven fabrics, a water-soluble yarn or a high-quality textile blended with other fibers, and a textile material for making military products.
Fabric processing has the largest demand for PVA, and the scope of use is roughly as follows: slurry - warp yarn, printing paste, fabric finishing; modifier - fabric resin finishing; adhesive - adhesive for felt and non-woven fabric.
In the above applications, the proportion used as the warp yarn slurry is the largest. PVA is an ideal low-cost warp yarn that enhances the warp cohesion, sizing strength, abrasion resistance, flexibility, and protection against changes in atmospheric conditions. There are hundreds of PVA pastes abroad, the main difference is the degree of alcoholysis and degree of polymerization, the most commonly used are 1799 and 1788.
(2) Paper processing PVA is mainly used in the paper industry for surface sizing agents, pigment binders and beater additives. Paper surface sizing agent made of PVA can enhance the surface strength and internal tension of the paper, crack resistance, folding and abrasion resistance, improve the gloss and smoothness of the paper, and improve the water resistance, oil resistance and organic solvent resistance of the paper. . Due to the strong adhesion of PVA aqueous solution to paper, the film forming property is good, and can replace the expensive and easily spoiled casein to make pigment adhesive. The coated paper has good whiteness and gloss, is not easy to curl, and has low cost. There are a wide range of uses for fine paper such as art paper and craft paper.
(3) Adhesives The adhesion of polyvinyl alcohol to cellulosic materials is extremely great. PVA is widely used as a binder for various fibrous materials and as a rewet adhesive for tapes, stamps, labels, and the like.
PVA with low degree of polymerization and low degree of alcoholysis can be used to make water-soluble hot melt adhesives which can be heated and melt coated on the surface of the substrate without the need for a drying process and good adhesion. In addition, it is not used as a trouble in the recycling of waste paper in the processes of wireless binding, corrugated cardboard, etc., and some resin hot melt adhesives such as EVA (ethylene-vinyl acetate resin) are hot melt adhesives, which are neither dispersed to water. Insoluble, when recycling waste paper, these adhesives form a block, which contaminates the paper and blocks the wire mesh in the papermaking process. PVA modified urea-formaldehyde resins and phenolic resins can be used to bond wood-based panels or composite panels.
(4) Films and products PVA aqueous solutions have good film forming properties, and PVA films have many different properties from other plastic films. There are many types of PVA films, such as soft films for fiber packaging, ionic films for molding such as polyester, water-soluble films, and films for food packaging.
PVA film has excellent performance as a packaging material: excellent transparency and gloss; no dust, no static electricity, good printing adaptability; high tensile strength and elongation, good wear resistance; low humidity, Excellent gas barrier and aroma retention, oxygen barrier even better than ethylene-vinyl alcohol copolymer (EVOH), and polyvinylidene chloride (PVDC); like EVOH, it has high moisture permeability and is sensitive to water; Good metal evaporation, thermal adhesion; excellent oil resistance, radiation resistance, can be used for radiation-resistant food packaging; soluble in water, hydrolyzable, biodegradable, hydrolyzed, degraded and incinerated in water It is an internationally recognized environmentally friendly material for CO2 and H2O.
The new formulation and process of polyvinyl alcohol film developed by Polyval of the United Kingdom can significantly reduce the cost of extruded polyvinyl alcohol film Engol. It is said that the conventional polyvinyl alcohol film is produced by a solution casting process, and the processing cost is very high. Now, the Enpol film is produced by Enpol resin extrusion blow molding. The melting point of Enpol resin is lower than the decomposition temperature of polyvinyl alcohol (about 180 °C). The company has produced and supplied Enpol resin and transferred film production technology. It has developed 10 grades. The processed film is soluble in water at different temperatures between 5 and 70 ° C for drainage system and can be used within three months. Biodegradable.
Polarizing films for liquid crystal displays (LCDs) are important electronic chemicals, and the world's demand is growing rapidly. The polarizing film is produced by stretching and combining a polyvinyl alcohol film and a triacetyl cellulose (TAC) film layer. The film can be taken by large roll pressing. The productivity of the polarizing film device can be improved by relaxing the rolling size. Kuraray is a leading producer of polyvinyl alcohol film. In order to meet the growing demand, Kuraray has nearly nearly doubled its optical polyvinyl alcohol film production capacity in 2005. Recently, Kuraray invested about 6 billion yen (about 51 million US dollars) in its Tamashima plant in Japan to expand the optical polyvinyl alcohol film of 30 million square meters per year. The expansion was completed in June 2007, which made Coke The total capacity of the company's polyvinyl alcohol film reaches 91 million square meters per year.
(5) Pharmaceutical field PVA is widely used as a new functional polymer material in medicine and pharmacy. When the blood vessel is docked, the PVA tube and the instant adhesive dissolved in a short time can be connected with one touch, which greatly simplifies the vascular anastomosis; PVA is used as a high-water-containing elastomer as a filling material for artificial joints, pericardium and pleura; Polyvinyl formal rubber sponge can be used to make artificial skin, artificial muscle, artificial cornea, glass, etc.; PVA can be used as dental restorative material; PVA hollow fiber has large surface area, can make artificial lung, PVA hollow fiber can be selectively infiltrated, can be manufactured Artificial kidney membrane; PVA water-soluble fiber as surgical suture, no need to remove the thread after surgery; PVA tear film can make tears to treat dry eye syndrome, PVA concentrated aqueous solution and ointment are evenly mixed to make surgical dressing, in trauma or trauma When a film is formed on the surface of the skin, the drug component can be sufficiently absorbed by the affected part without contaminating the clothes.
PVA has been more commonly used in pharmacy, and the addition of PVA to the drug controls the rate of drug release. When the PVA-containing drug is dissolved, the surface first absorbs water and swells to form a gel, thereby preventing moisture from penetrating into the center of the material. After the gel is gradually dissolved, the water gradually enters and the drug is gradually absorbed, thereby preparing a sustained-release and constant-release tablet. Agent, enteric agent; liquid agent added PVA to increase the viscosity of the drug to achieve long-term effects, to make long-acting ophthalmic agents.
Israel's Regal Biomaterials has developed a cartilage repair hydrogel. The hydrogel consists of polyvinyl alcohol and a proportion of fibrinogen. It is a biodegradable synthetic material that can be infused into the desired shape after being injected into the injured part of the cartilage, and induced by the released fibrinogen. The chondrocytes are regenerated and naturally fused with the surrounding tissue.
(6) Emulsifying stabilizer Partial alcoholysis PVA has lower surface tension than full alcoholysis PVA, so that the dispersion of vinyl acetate monomer in water is large, and the protective rubber has good performance. PVA is not only a protective colloid suitable for vinyl acetate emulsion polymerization, but also a thickener for polyvinyl acetate emulsion, so it plays an important role in the polyvinyl acetate emulsion industry.
The use of emulsifier type PVA as emulsion stabilizer and thickener for vinyl acetate emulsion polymerization can make emulsion particles small, high viscosity of emulsion; less foaming, so no trouble of foam condensation, good freeze-thaw stability; and pigment or inorganic salt The mixing is good; the post-adding viscosity-increasing effect is large.
(7) Soil improver Polyvinyl alcohol as a soil improver makes the soil granulation ability superior to any other improver. The soil improved by PVA: 1 pores, so that the air content is high, the soil is loose, and the microbial activity is good. Promote root development; 2 The capillary of the soil is intricate, the water is kept well; 3 the gap between the particles is large, and the water permeability is good.
(8) Others In addition to these mature applications, the new use of PVA is constantly expanding. For example, people have conducted screening studies on various biodegradable polymer materials, and it has been shown that PVA is a biodegradable material among large-sized synthetic polymers. Bio-degradation can be obtained under the corresponding conditions by modifying the PVA or adding other polymer materials to produce medical equipment, food packaging, office supplies and sanitary materials.
An important feature of PVA is its hygiene. Many research institutes in the United States and Japan have conducted a large number of tests on PVA to prove that it is non-toxic. In addition to not being used as an internal medicine or food directly into the human body, its contact with the skin is completely harmless and can be used in the fields of cosmetics and food packaging.

The high-strength and high-mold fiber made of PVA as the main raw material is a new family of vinylon fiber series. It has the advantages of high strength, high modulus and good dispersibility, and is resistant to acid, alkali, salt, abrasion, light, corrosion, insects, and has good affinity with cement. It is ideal for cement products. Enhanced anti-cracking material. In addition, because of its high temperature and high temperature properties, high strength and high modulus vinylon will play an important role in the very demanding rubber field. For example, the strong rayon that constitutes the tire material has already been eliminated, and the high-strength high-modulus vinylon will be fully hopeful to become the radial tire cord. High-strength and high-modulus vinylon is also entering the field of plastic reinforcement materials with its unique advantages of high modulus and high strength.
we are professional fine chemicals materials supplier from china. other products like Caustic Soda Flake,refined glycerine,1 2-hexanediol etc.