PVA 1788

Vinylon is the trade name of polyvinyl acetal fiber, also known as Vinylon. Its performance is close to cotton, known as 'synthetic cotton', is the largest variety of existing synthetic fibers in hygroscopicity. It is not easy to ignite, near the flame melting contraction, there is a little flame at the top of the burning, when the fiber is melted into a gel, the flame becomes larger, there is thick black smoke, emitting bitter aroma, and the black small beaded particles are left after burning, which can be crushed by fingers.   Vinylon is the most hygroscopic variety in synthetic fibers, with a hygroscopic rate of 4.5% to 5%, close to cotton (8%). Vinylon is soft and warm, and its relative density is smaller than cotton, so the same weight of Vinylon with cotton can weave more clothing. Its thermal conductivity is low, so the warmth is good. The wear resistance and strength of Vinylon are also better than cotton, so Vinylon can be blended with cotton in many ways to save cotton. Vinylon is mainly used in the production of garments, cotton sweaters, pants, sweatshirts and other knitted fabrics, can also be used in canvas, fishing nets, surgical stitches, bicycle tire cord, filter materials. More and cotton blend: muslin, poplin, corduroy, underwear, canvas, tarps, packaging materials, work clothes, etc.   The main component of Vinylon is polyvinyl alcohol(PVA), but vinyl alcohol is unstable, generally with stable performance of vinyl alcohol acetate (that is, vinyl acetate) as a monomer polymerization, and then the generated polyvinyl acetate alcohol hydrolysis to polyvinyl alcohol, spinning and then treated with formaldehyde, in the polymer chain to introduce a six-membered ring structure to generate polyvinyl formaldehyde, enhance its strength. To get water resistant Vinylon.   The manufacture of industrial vinylon fiber is to dissolve polyvinyl alcohol in water to produce about 15% aqueous solution, through the spinneret with a diameter of about 0.07 mm, in the saturated sodium sulfate aqueous solution solidification bath to produce fiber, and then stretching and heat treatment to improve strength and heat resistance; Then in the presence of catalyst sulfuric acid, acetal reaction with formaldehyde, the temperature is about 70℃, the time is 20 to 30 minutes, after washing, oil to obtain Vinylon fiber. Vinylon fiber has short fiber, tow and filament and other varieties, of which cotton type short fiber and tow are the most common.   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 different mesh numbers of PVA should be selected according to the specific application needs, to ensure the best effect. The mesh number of PVA indicates its particle size, the larger the mesh number, the smaller the particle diameter. For example, ‌120 purpose polyvinyl alcohol particle size is smaller, ‌under the action of surfactants, can be better adsorbed and coated by liquid, the lubricity, and other properties are better than 80 purpose polyvinyl alcohol. ‌, therefore, ‌ when it is necessary to use polyvinyl alcohol, ‌ should be selected according to the specific application needs of different mesh of polyvinyl alcohol. In addition, the common mesh of ‌ polyvinyl alcohol includes 12 mesh, 20 mesh, 25 mesh, ‌80 mesh and 120 mesh, ‌ grinding into powder can improve the dissolution rate of polyvinyl alcohol, ‌ but not the finer the better, the powder will lump as long as it is soaked with water, especially when the dosage is large. On the contrary, it is not conducive to the dissolution of PVA.    When dissolving more than 80 mesh PVA powder, pay attention to the way of adding, need to stir quickly, add slowly, to prevent more powder together when encountering water. Dissolved larger particles of powder below 80 mesh PVA basically will not lump, but at room temperature dissolution is slower, you can stir or increase the dissolution temperature, thereby accelerating the dissolution of PVA.   Therefore, the appropriate mesh number should be selected according to the different requirements of the product and the situation of the reactor of the existing equipment.   ElephChem can provide a variety of PVA powder with different mesh sizes, welcome to consult: 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.

Using the existing coating machine, dry composite machine and other equipment of domestic flexible packaging enterprises, after coating PVA coating solution of only 0.5g/m2 ~ 0.8g/m2 (dry base) on the film with qualified surface tension (such as PET, BOPP, CPP, PE and other films), The oxygen permeability of the film is less than 2cm3/ (m2·24h·0.1MPa), or even less than 0.5cm3/ (m2·24h·0.1MPa). Obviously, the oxygen resistance of the product has been significantly better than the five-layer co-extruded film with EVOH as a barrier layer and PVDC high barrier coating film, which is close to the oxygen resistance of aluminum foil. Advantages1, high cost performanceThe production cost of modified PVA coated high barrier film is much lower than the production cost of paper aluminum-plastic composite and aluminum-plastic composite structure packaging materials, and also lower than the cost of PVDC coated composite film. 2, excellent oxygen resistanceThe modified polyvinyl alcohol (PVOH) composite film has good barrier property to oxygen, nitrogen, hydrogen and carbon dioxide, and its oxygen inhibition property is much better than PVDC composite film. 3, excellent perfuming performanceIt can maintain the original flavor of the food in the bag for a long time, and at the same time, it can effectively prevent the odor outside the packaging material from entering the bag. 4, excellent environmental protection materialsPVA coating liquid is composed of carbon, oxygen, hydrogen and silicon, which can be degraded, recycled and reused, and does not produce toxic gases after combustion. It is an ideal packaging material.   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 defoamer is a kind of surfactants commonly used in the chemical field, and it is widely used in the chemical industry. Its main role is in the production process, can effectively reduce the foaming phenomenon, also known as foaming agent or foam inhibitor.   Properties of polyvinyl alcohol defoamer 1. With low surface tension, it can effectively destroy the tension on the surface of the liquid, so that the liquid molecules repel each other, and the molecular combination will no longer occur to produce foam.2.Polyvinyl alcohol defoamer has good dispersion performance, which can re-disperse dispersed bubbles in the liquid, thereby avoiding foam deposition and reducing energy waste.3. PVA defoamer can form a relatively stable dispersed liquid system, making its distribution in the liquid more uniform, thereby reducing the generation of foam.4. Its role is to change the interaction force between molecules, and the physical and chemical properties of the solution have no obvious relationship, will not affect the composition of the solution and chemical reaction.   The role of PVA defoamer in production 1. Reduce energy consumptionThe application of PVA defoamer can effectively reduce the resistance of air and bubbles to liquid, reduce the consumption of pumping energy and stirring energy, and thus save energy.2. Improve production efficiencyIn some special occasions, the generation of foam will have a negative impact on production efficiency, the use of PVA defoamer can effectively reduce the generation of foam and improve production efficiency.3. Improve product qualityThe use of polyvinyl alcohol defoamer can effectively control the foam generation, reduce the tension of the liquid surface, make the product surface more flat and smooth, so as to improve the product quality. To sum up, PVA defoamer is one of the excellent surfactants, which is widely used in various industrial fields. In practical application, we should choose the corresponding defoamer according to the specific production needs to achieve the best effect.   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 1788 is a colorless, transparent, viscous polymer compound consisting of alternating arrangements of vinyl and hydroxyl units. It is often used in the preparation of glue, coatings, textiles, medicine and other fields.   Polyvinyl alcohol 1788 has good solubility, can be dissolved in water, can also be dissolved in alcohols, esters and other organic solvents. Its solubility decreases with the increase of molecular weight. In dry air, PVA 1788 is relatively stable, but it breaks down in sunlight.   Polyvinyl alcohol 1788 is an important polymer material, which is widely used in various fields. The main uses of PVA 1788 are as follows: 1. Glue preparationPVA 1788 can be used to prepare various glues, such as woodworking glue, paper glue and so on. Dissolve PVA 1788 in water, then add crosslinking agent and auxiliary agent, after stirring, filtration, defoaming and other process steps, you can get glue. 2. Coating preparationPVA 1788 can be used to prepare various coatings, such as wall coatings, wood coatings and so on. The polyvinyl alcohol 1788 is dissolved in water, and then added pigments, fillers, auxiliaries, etc., after mixing, grinding, filtration and other process steps, the paint can be obtained. 3. Textile processingPVA 1788 can be used in textile processing, such as the processing and printing of cellulose fibers. Dissolve PVA 1788 in water, then add dyes, additives, etc., after soaking, drying and other process steps, dyed cellulose fiber can be obtained. 4. The field of medicinePVA 1788 can be used to prepare medicine, such as oral medicine, injections, eye drops and so on. Dissolve PVA 1788 in water, then add drugs, auxiliaries, etc., after mixing, filtration, sterilization and other process steps, you can get the drug.   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.

Dispersion polymerization is another kind of heterogeneous free radical polymerization of alene monomers except suspension polymerization and emulsion polymerization. Dispersion polymerization can be regarded as a polymerization between suspension polymerization and emulsion polymerization, and its characteristics are as follows: 1) Water or non-water solvent can be used as the medium. When water is used as a medium, the monomer must be insoluble in water or substantially insoluble in water.2) The dispersion of monomers in water is achieved by intense agitation, and the protective colloid added to the system plays a role in preventing the agglomeration of dispersed phases.3) Water-soluble initiators are required for dispersion polymerization with water as the medium.   In form, dispersion polymerization has many similarities with emulsion polymerization. But there are clear differences. Dispersion polymerization, for example, does not use typical emulsifiers but uses protective colloid to stabilize the polymerization system; The particles obtained by polymerization are larger than those obtained by emulsion polymerization. Let's wait.The polymerization of vinyl acetate in water with polyvinyl alcohol as a protective colloid is a typical dispersion polymerization. Vinyl acetate is a water-soluble monomer with a solubility of about 2.5% in water at room temperature and is easily hydrolyzed. The hydrolysis product acetic acid can seriously interfere with the normal process of polymerization. Therefore, the dispersion polymerization of vinyl acetate has more complicated factors than the common emulsion polymerization. It is believed that the dispersion polymerization of vinyl acetate does not occur in micelles, but the monomer dissolved in water is first polymerized, and when the molecular weight reaches a certain level, the polymer precipitates from the water to form latex particles on the protective colloid. In order to improve the stability of the polymerization system and products, an appropriate amount of emulsifier is added in the dispersion polymerization of vinyl acetate, but the role of emulsifier in polymerization is auxiliary.   Attentions： PVA usually has two specifications of 1788 and 1799 (17 indicates a degree of polymerization of 1700, 88 and 99 indicate an alcoholysis degree of 88% and 99%, respectively). When used as a dispersion polymerization protective colloid, it is best to use 1788, and the resulting product has good stability.2. In the polymerization process, the monomer droplet acceleration should be slow and not fast. Generally, a slight reflux in the condenser is appropriate.3. The boiling point of vinyl acetate is between 70-75℃. After adding drops, the heating rate should be slow, too fast and easy to caking.   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 production process of polyvinyl alcohol can be divided into ethylene method and acetylene method according to raw materials. Acetylene synthesis can be divided into calcium carbide acetylene synthesis and natural gas cracking acetylene synthesis according to the different sources of raw materials. Calcium carbide acetylene synthesis, the first to achieve industrial production. Due to the high energy consumption, low quality and high cost of the products of this process route, the impurities generated by the production process pollute the environment is also more serious, and the lack of market competitiveness is gradually eliminated. In areas rich in natural gas, coal and electric power, natural gas acetylene synthesis is still vital.The process of synthesis of polyvinyl alcohol by ethylene method includes five steps: obtaining ethylene and synthesis of vinyl acetate, rectification, polymerization, alcoholysis of polyvinyl acetate (PVAc), recovery of acetic acid and methanol.   Vinyl acetate polymerization:   After preheating, ethylene acetate was mixed with solvent methanol and initiator azodiisobutyronitrile and sent to two tandem polymerization reactors for polymerization at 66 ~ 68℃ and atmospheric pressure. After polymerization for 4 ~ 6H, about 2/3 of vinyl acetate was polymerized into polyvinyl acetate. The heat generated by the polymerization reaction can be carried away by the evaporation of methanol, and the methanol vapor is condensed and returned to the polymerization kettle. The polymerization liquid is sent to the monomer to blow out the tower, and the unpolymerized vinyl acetate is blown out with methanol vapor. The ethylene acetate and methanol blown by the monomer blowout tower are separated and distilled, recovered and recycled. The polymerization solution was sent to the alcoholysis section for alcoholysis with methanol adjusted to 33% polyvinyl acetate.   Polyvinyl acetate alcoholysis: Polyvinyl acetate and sodium hydroxide methanol solution were mixed into a high-speed mixer at the ratio of polyvinyl acetate: methanol: sodium hydroxide: water at 1∶2∶0.01∶0.002 at the same time, and then entered the belt alcoholysis machine for alcoholysis at 50℃. The belt was moved at a speed of 1.1 ~ 1.2m/min, and the alcoholysis was completed in about 4 minutes. To obtain cured polyvinyl alcohol. After the solvent was removed by grinding, pressing and drying, the finished polyvinyl alcohol was obtained.   Recovery of methyl acetate: The extruded liquid contains a lot of methyl acetate and methanol. First, the azeotrope of methyl acetate and methanol is steamed in the azeotrope distillation column, and the bottom of the column is methanol aqueous solution. Methyl acetate and methanol azeotrope into the water extraction separation column and mixed with water, the top of the column separated methyl acetate, the bottom of the column is methanol aqueous solution. Methyl acetate was catalyzed by ion exchange resin in a hydrolyzer to obtain a mixture of acetic acid and methanol. The mixture is sent to a hydrolysate distillation column, where methanol and unhydrolyzed methyl acetate are steamed out and fed into a water extraction separation column. The bottom of the hydrolysate distillation column is dilute acetic acid, which is obtained after being sent to the dilute acetic acid concentration column to remove the water. The methanol aqueous solution obtained from the bottom of the azeotropic distillation tower and the water extraction separation tower can be reused by steaming the methanol in the methanol distillation tower.   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.  

There are differences between polyvinyl alcohol(PVA) fiber and polyester fiber in chemical structure, physical properties and application fields.   First, the chemical structure of polyvinyl alcohol fiber and polyester fiber is different PVA fiber contains a large number of hydroxyl (-OH) functional groups in its molecular structure, so it has good hydrophilicity and solubility. In the molecular structure of polyester fiber, it mainly contains ester group (-COO-) function group, so it has good water resistance and durability.   Second, the physical properties of PVA fiber and polyester fiber are differentThe tensile strength and modulus of polyvinyl alcohol fiber are low, but it has better softness and bending property. Polyester fibers have higher strength and modulus, but are relatively hard and easy to break. In terms of heat resistance, polyester fiber shows good performance and can withstand high temperature processing; The polyvinyl alcohol fiber is easy to melt and decompose at high temperatures.   Third, the application fields of polyvinyl alcohol fiber and polyester fiber are different Due to the different characteristics of polyvinyl alcohol fiber and polyester fiber, they have their own application advantages in different fields. Polyvinyl alcohol fiber is often used in textile, paper processing, plastic film and other fields, and can also be made into waterproof, moisture-proof, anti-static and other functional fibers. The polyester fiber is often used in the production of clothing, fabrics, ropes and other products with high strength and wear resistance, and is also often used in the production of various plastic products.   In short, there are significant differences between polyvinyl alcohol fiber and polyester fiber in their respective chemical structures, physical properties and application fields. Therefore, in actual production and application, product designers and producers need to choose suitable materials according to different needs.   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 2488(PVA 088-50) is a white small granular, stable and non-toxic water soluble polymer, mainly used as building mortar additive and dry mortar field.   PVA 2488 is especially suitable as a mortar additive, which can be used with cellulose ether water retaining agent to improve the flexibility and water retention of cement mortar and gypsum building materials, and improve the viscosity of mortar. In addition, it can also reduce the friction of the mortar, thereby enhancing the working efficiency and quality, preventing the cracking and falling off of the plaster layer, and increasing its adhesion strength and smoothness. The bonding strength of PVA powder is 2.5-3 times higher than that of redispersible emulsion powder, and the service life is long, which can greatly reduce the production cost.   PVA 2488 in ash calcium base putty can significantly improve the cohesion strength, adhesion and water resistance of putty coating. At the same time, it can also significantly improve the phenomenon of delamination scars during grinding, and improve the surface fineness of the putty after grinding. In addition, PVA powder can also accelerate cement solidification in cement-based putty, and has excellent film forming property.   PVA 2488 is one of the main binders of instant glue powder, which can be combined with an appropriate amount of hydroxypropyl methyl cellulose and supplemented with an appropriate amount of thickening and complexing additives to obtain environmentally friendly and high bonding strength double fly powder. At the same time, the product can also be mixed with cement gypsum for wet wall leveling.   The amount of PVA 2488 can be adjusted according to the specific use situation. In gray calcium base putty, the recommended addition amount is 0.3%-0.8%. The amount used in building mortar is also minimal. One ton of gouache in instant glue powder only needs to add 1 kilogram of PVA 2488.   PVA 2488 also has a variety of other uses, such as cosmetics, screen sensitive film, coated paper coating agent, zinc plate printing sensitive film, long fiber yarn sizing agent.   ElephChem Holding Limited, professional market expert in Polyvinyl Alcohol, can provide you with quality products and services. Welcome to inquire, please click the URL or email below: Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com

The average molecular weight of polyvinyl alcohol used as raw material for polyvinyl alcohol fiber is 60000 ~ 150000, the thermal decomposition temperature is 200~220 ℃, and the melting point is 225~230 ℃. Polyvinyl alcohol fiber can be prepared by wet spinning and dry spinning.   Polyvinyl formaldehyde fiber can be obtained by the acetal treatment of the heat treated polyvinyl alcohol fiber. The process of acetalization is the process of washing the strands to remove sodium sulfate, passing through the aldehyde solution, and then washing. The tow can also be cut into short fibers and transported by air to the aftertreatment machine for acetal treatment on the stainless steel net.   In order to improve the fiber properties, the polyvinyl alcohol solution containing the crosslinking agent boric acid (the concentration is 16%) can be wet-spun, and the resulting primary fiber is solidified in the alkaline coagulation bath, and after neutralization, washing and multi-stage high tensile and heat treatment, the strength of 106 ~ 115cN/dtex filament can be obtained.   PVA fibers are used in the industrial field to make canvas, tarps, filter cloth, transport belts, packaging materials, work clothes, fishing nets and cables for Marine operations. High strength, high modulus filament can be used as a transport belt skeleton material, a variety of rubber hose, rubber cloth and rubber shoes lining material, can also make bicycle tire cord.   Because this fiber can resist the alkalinity of cement, and has good adhesion and affinity with cement, it can replace asbestos as the reinforcing material of cement products. It can be blended with cotton to make a variety of clothing and indoor goods, and can also produce knitwear. However, the heat resistance is poor, the fabric is not crisp, and can not be washed in hot water. In addition, it is also useful in non-woven fabrics and papermaking.   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 fiber (referred to as PVA fiber) is a kind of synthetic fiber which is processed by using specific advanced technology and is made of high-quality polyvinyl alcohol (PVA) with high polymerization degree as raw material.   The main characteristics of polyvinyl alcohol fiber are high strength, high modulus, low elongation, wear resistance, acid and alkali resistance, good weather resistance, and cement, gypsum and other substrates have good affinity and combination, and non-toxic, pollution-free, does not damage the human skin, harmless to the human body, is one of the new generation of high-tech green building materials. Polyvinyl alcohol (PVA), the raw material for the production of Vitellin fiber, is a water-soluble polymer with properties between plastics and rubber and is widely used. China's PVA production capacity and output rank first in the world, followed by Japan, the United Kingdom and North Korea.   Polyvinyl alcohol fiber can be produced by wet spinning and dry spinning, the average molecular weight of the raw material polyvinyl alcohol is 60000 ~ 150000, the thermal decomposition temperature is 200 ~ 220℃, and the melting point is 225 ~ 230℃. After heat treatment, the polyvinyl alcohol fiber was acetalized to obtain polyvinyl formaldehyde fiber. It is called Vinylon in the world.   The polyvinyl alcohol fiber can be blended with other fibers, and then dissolved after textile processing to obtain fine yarn high-grade textiles, and can also be made without twist yarn or weft free blankets. It can also be used as an adhesive for paper making to improve the strength and toughness of paper. In addition, it can also make special purpose overalls, surgical sutures, etc.   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 is a strong hydrophilic and active organic compound that is commonly used as a binder in paper and printed matter. Polyvinyl alcohol has excellent plasticity and fluidity, and can be used for the coating and packaging of printed matter. Due to its excellent physical and chemical properties, polyvinyl alcohol has been widely used in colorful printing. And provides a variety of roles in colorful printing.   1. Fix the paint Pva can be used as a paint to fix colored pigments and prevent them from spreading on the paper. At the time of printing, PVA can be mixed with pigments to form a pigment paste, which is then printed directly on paper by a printing press. This printing method can ensure the accuracy and consistency of the color. At the same time, through the adsorption of polyvinyl alcohol and paper, the pigment can be firmly attached to the paper and is not easy to fall off.   2. Enhance the toughness and brightness of printed matter In colorful printing, polyvinyl alcohol can also be used as a coating, which can greatly enhance the toughness and brightness of the print. Through the coating treatment of PVA, the printed matter can better resist the influence of external factors such as water and wiping. In addition, the coating of PVA can make the print more beautiful and increase the decorative effect of the print.   3. Other advantages Pva has other advantages. First of all, polyvinyl alcohol is non-toxic, tasteless, safe for human body, and can be used with confidence. Secondly, polyvinyl alcohol can remain stable in a high temperature and high humidity environment, and will not lose its physical and chemical properties due to environmental changes. Finally, the price of polyvinyl alcohol is relatively low, and the use cost is low.   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 088-20 & PVA 1788 PVA 100-27 & PVA 1799 PVA 088-50 & PVA 2488