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Butvar brand resins generally are soluble in alcohols, glycol ethers, and certain mixtures of polar and nonpolar solvents. In general, Butvar B-98 (PVB Resin B-05SY) resin will show the same general compatibility characteristics as Butvar B-90 (PVB Resin B-02HX) and, therefore, should prove advantageous where physical and chemical properties of B-90 are desired but lower solution viscosities are necessary. The same is true for Butvar B-79 in relation to Butvar B-76.     The lower hydroxyl content of Butvar B-76 and Butvar B-79 permits solubility in a wider variety of organic solvents as compared to the other grades of Butvar. One notable exception, however, is the insolubility of Butvar B-76 and Butvar B-79 in methanol. All other types of Butvar contain sufficient hydroxyl groups to allow for solubility in alcohol and in hydroxyl-containing solvents. The presence of both butyral and hydroxyl groups permits solution in mixtures of alcohol and aromatics. Viscosities of Butvar resin solutions containing mixed solvents depend on the ratio of alcohol to aromatic. Viscosity curves for Butvar B-76, Butvar B-90, and Butvar B-98 in Graph 2 show minimum points in the general vicinity of 50% alcohol: 50% aromatic.     A common solvent for all of the Butvar resins is a combination of 60 parts toluene and 40 parts ethanol (95%) by weight. For compositions of Butvar, methyl alcohol will tend to give the lowest viscosity and, therefore, will permit the use of higher solids when used as a component of a solvent blend. When much more than 10% to 15% alcohol is used in a formulation for spray application, blushing may result. They are useful as starting points in the development of solvent blends for the other types.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com

The different kinds of Butvar resins have their properties laid out in Tables 1 to 5. These resins come in various molecular weights and viscosities. Butvar 76 and Butvar 79 resins have less hydroxyl content compared to other Butvar options, which gives them better solubility.   Generally, when you swap butyral groups for acetate groups, you get a polymer that repels water better and can handle heat more without deforming. This change also boosts the polymer's strength and how well it sticks to different surfaces. The strong sticking power of polyvinyl butyral resins comes from their terpolymer structure. Since each molecule has a choice of three different functional groups on its surface, the likelihood of adhesion to a wide range of substrates is significantly increased.   Although polyvinyl butyral resins (PVB) are generally thermoplastic and soluble in a number of solvents, they can be crosslinked by heat and small amounts of mineral acid.Crosslinking often happens through transacetalization, but it can also be due to more complicated processes, like reactions between acetate or hydroxyl groups on nearby chains.   In practice, crosslinking of polyvinyl butyrals is achieved by reaction with various thermosetting resins such as phenolic, epoxy, urea, dicyanate, and melamine resins. The availability of functional hydroxyl groups in Butvar resins for this type of condensation is an important factor in many applications. Including even a small amount of Butvar resin in thermosetting compositions will significantly improve the strength, flexibility, and adhesion of the cured coating.     Polyvinyl butyral films are known for their great resistance to various substances like aliphatic hydrocarbons and different kinds of oils, except for castor and gypsum oils. They tolerate strong bases, but are sensitive to strong acids. However, when used as components of cured coatings, their resistance to acids, solvents and other chemicals is greatly increased. Butyral withstands temperatures up to 200°F for long periods with little color change.   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  

The scientific name of PVB resin is polyvinyl butyral resin. It was successfully industrialized in the United States in the 1930s and has a history of more than 70 years. my country has been trying to industrialize it since the 1960s, but due to the sensitivity of raw materials and process parameters, the product quality fluctuates greatly. The few finished products can only meet military purposes. It was not until the 1990s that a small amount of PVB (B-06HX &PVB B-20HX) products entered the civilian market.   Due to the different processes of PVB manufacturers, the requirements for PVB quality indicators are also different. Not only are there certain restrictions on the viscosity range, but there are also clear requirements for many indicators such as acetalization degree, tensile strength, and film-forming properties. Therefore, it is very easy to make PVB resin. However, it is quite difficult to make products that satisfy users. In order to produce PVB resins that meet user needs and improve the qualified rate of products, the following countermeasures should be taken:   Carefully select raw materials PVA PVA has a variety of models (such as PVA 088-50 & PVA 2488, Mowiol 47-88), not only with different degrees of polymerization, but also with different degrees of alcoholysis. To figure out how much acetalization you need, pick a PVA that meets the viscosity requirements. Try to keep the process conditions the same so that the product quality stays good without putting in extra effort. Process control programming At present, the production of China PVB resin adopts two-step precipitation method, kettle operation, and intermittent production. The production control is mainly manual control, which is quite arbitrary, especially the viscosity of PVB. The viscosity changes greatly with a slight change in the process.It's a good idea to use a DCS control system for making PVB resin. Stick to a programmed operation and keep the process steps pretty much the same for each customer. Strict finished product management It is best to adopt order-based production, and deliver it to customers in time after production is completed. Products that have not been delivered to customers must be placed separately and must not be mixed. For products that have been parked in the warehouse for more than one month, re-sampling and analysis are required before leaving the factory to prevent degradation of PVB resin powder. Disposal of unqualified products Some products may not meet the requirements of a certain user for individual indicators, but there is no problem with the quality of the batch of products itself. The usual practice is to find users with the same or similar quality as the batch of products and make appropriate treatments based on the degree of compliance. If the same products can be sent directly to the user, if the same products are not met, measures such as return package and add can be taken. Products with quality problems can only be sold as waste or destroyed.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com  

Polyvinyl alcohol (PVA) is an important chemical raw material, used to make polyvinyl acetal, gasoline-resistant pipes and vinylon synthetic fibers, fabric treatment agents, emulsifiers, paper coatings, adhesives, glues, etc.     Different grades Polyvinyl alcohol is obtained by hydrolysis of polyvinyl acetate, but not directly by polymerization of vinyl alcohol. Because vinyl alcohol is extremely unstable, it is impossible to have free vinyl alcohol monomers.   Different degree of polymerization There are generally three kinds of alcoholysis degree, namely 78%, 88%, and 98%. Completely hydrolyzed polyvinyl alcohol is obtained by hydrolyzing polyvinyl acetate with a degree of hydrolysis of 98% to 100%. The degree of hydrolysis of partially hydrolyzed polyvinyl alcohol is generally 87% to 89%. To keep things simple, the numbers for polymerization are usually listed first, followed by the percentage of hydrolysis. So, PVA-1788 (Poval 217) means it has a polymerization degree of 1700 and a hydrolysis degree of 88%.   Different water solubility PVA-1788 is well soluble in water and can be quickly dissolved in cold water or in boiling water. The viscosity of PVA-2488 (Mowiol 47-88) is 1.5-2 times that of 1788 (different manufacturers' grades). The dissolution process of 2488 is longer than that of 1788, and its tensile force after dissolution is greater than that of 1788.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com  

With the continuous development of science and technology, PVA (polyvinyl alcohol) is an important polymer compound and is widely used in various fields. In the market, PVA has many different models, and there are certain differences and characteristics between them. Next, we will introduce the differences and application scenarios of various PVA models in detail.   Let's discuss one of the common PVA models-PVA-1788. PVA-1788 has a high degree of polymerization and alcoholysis, and its solubility is good. It can be used to prepare high-transparency hydrogel products. Due to its unique physical properties, PVA-1788 is widely used in the medical and health fields, such as making waveforms to simulate human tissue. PVA-1788 can also be used as a film-forming agent for electrolyte and nutrient sustained-release systems, and is used for soil improvement in the agricultural field.     Another common model is PVA-117. Compared with PVA-1788, PVA-117 has a lower degree of polymerization and a slightly higher degree of alcoholysis. This makes PVA-117 easier to dissolve in water, and has good adhesion and fluidity, making it widely used in the preparation of adhesives. Not only that, PVA-117 can also be used as a stabilizer for the preparation of iron oxide nanoparticles, as well as an emulsifier in coatings, etc.     There is also a special type of PVA, namely PVA-217. PVA-217 is characterized by a low gelation temperature, good thermal stability, and is widely used in the fiber field. In the textile industry, PVA-217 can be used for needle spinning to give the yarn a higher tensile force and lower breaking strength. PVA-217 can also be used as a cross-linking agent for cellulose fibers, playing an important role in the textile processing process.   In summary, PVA, as an important polymer compound, has different types of products to choose from in different application fields. PVA-1788 is suitable for medical and health and agricultural fields, while PVA-117 is widely used in adhesives and coatings, and PVA-217 is mainly used in the textile field.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com

  Production process of PVB:   Currently,Polyvinyl Butyral Resin (PVB) is mostly produced using an extrusion casting method. China has made some high-end PVB in the past, especially for the military, like in aircraft and military vehicles, but there hasn’t really been a large-scale market for it.   Since the technology behind PVB is a closely guarded trade secret, we don’t have a clear public description of the process. Still, we can get a rough idea from technical documents: 1. First, the raw materials are fed into different extruders by the feeding system, and the pellets are evenly plasticized and molten in the extruder by heating; 2. The molten body passes through the filter to remove impurities; 3. The melted material flows out through the adjustable discharge port after removing the impurities until it cools down and takes shape as a film. 4. The film passes through the automatic X-ray measurement system to see if the thickness meets the technical requirements; 5. After the film goes through processing, it gets treated on the surface, trimmed, wound automatically, and cut into shape. At this point, it's ready as a final product.   For PVB film, it’s important that the surface is flat. If the film is 0.76mm thick, any thickness variation should be no more than 0.02mm. When measuring in both vertical and horizontal directions over a range of 50mm, the error should be under 0.006mm. Also, the moisture content has to stay below 0.3%, and the natural rating should be under 12%.     The technical difficulty of PVB production：   In terms of process, the ratio of polyvinyl butyral resin and plasticizer is one of the key points to determine the quality. In addition, since PVB has high requirements for humidity, special treatment is required during slitting, packaging, storage, and transportation;PVB needs specific humidity levels, so we have to be careful with slitting, packaging, storing, and transporting it. Plus, to make high-quality PVB, we need good resin, which means new projects will need extra resin production areas. This adds some new challenges for managing the process.   For PVB (such as Butvar B-74) in the solar industry, there are extra demands for resistivity and temperature compared to what’s needed for regular car glass or curtain walls. Usually, the resistance furnace requires more than 1000 ohms/cm2; the temperature must be lower than the tolerance temperature of the film to avoid damaging the reaction layer.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com

PVA (polyvinyl alcohol) is a white, powdery resin obtained by hydrolysis of polyvinyl acetate. Since my country began researching and producing it in the 1960s, its current output ranks first in the world. Polyvinyl alcohol film is great because it's really clear, lightweight, and can keep gases out. It's tough, won't tear easily, and can handle wear. Plus, it can dissolve in water and break down naturally under the right conditions. It is one of the new green materials that has developed rapidly in recent years.   At present, the high-barrier packaging materials on the market mainly include polyvinylidene chloride (PVDC), ethylene-vinyl alcohol copolymer (EVOH) and polyvinyl alcohol (PVA). Polyvinylidene chloride (PVDC) is mainly used in the coating process. PVDC has good oxygen and water vapor barrier properties, and the coating can be heat-sealed with low cost. However, PVDC because of the chloride ions in its structure, it cannot be recycled and reused. When the waste is incinerated, it will also produce hydrogen chloride, dioxins and other toxic and harmful substances to the human body and the surrounding environment. Europe and the United States have begun to restrict its use.     Ethylene-vinyl alcohol copolymer (EVOH) has excellent barrier properties and excellent processability. It has excellent transparency, gloss, mechanical strength, elasticity, wear resistance, cold resistance and surface strength. It only produces CO2 and H20 when incinerated, and is an excellent green and environmentally friendly packaging material. However, when the ambient temperature is relatively high, its barrier properties deteriorate sharply, so it is not suitable for use alone. It is mostly used in the production of multi-layer co-extruded films, such as EVOH five-layer co-extruded films, but most of the equipment relies on imports and is costly.   Polyvinyl alcohol (PVA,PVA 2688 & PVA 088-60) contains a large number of hydroxyl groups in its molecular structure and has hygroscopic energy. As the humidity increases, its gas barrier function decreases. It needs to be coated or plasticized in large quantities before it can be processed and formed. Therefore, the modified PVA coating film that has been hydrophobically modified is often used in the coating process. It has been widely used in the United States and Japan, and has begun to flourish in my country in recent years.   The continuous development and progress of society has prompted people to put forward more requirements and expectations for new materials that are safe, environmentally friendly, degradable and recyclable. The development of the technology of modified PVA coating film that has emerged will not stop. The booming plastic processing industry calls for the birth of new generations of new products. It can be expected that in the near future, as the technology of modified PVA coating film becomes more mature, its share in the structural grade and economic benefits of plastic packaging market products will become larger and larger.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com

Polyvinyl butyral resin (PVB) is a solvent-based resin synthesized by acetalization reaction of polyvinyl alcohol (PVA ) and butyraldehyde under the action of coal catalyst     General characteristics The appearance of PVB is white spherical porous particles or powder, and its specific gravity is 1:1; but the filling density is only 0.20~0.35g/ml. Thermal properties The glass transition temperature (Tg) of PVB ranges from 50℃ for low overlap to 90℃ for high overlap; this glass transition temperature can also be adjusted to below 10℃ by adding an appropriate amount of plasticizer. Mechanical properties PVB has excellent film-forming properties and gives the coating film quite good properties such as warp strength, tear strength, abrasion resistance, elasticity, flexibility, gloss, etc.; it is especially used in bonding safety glass interlayers, making the glass have strong impact resistance and penetration resistance, and it is still not replaced by other materials. Chemical properties PVB coatings have good water resistance, resistance and oil resistance (resistance to aliphatic, mineral, animal and plant oils, but not castor oil). Because PVB contains high hydroxyl groups and has good dispersibility for pigments, it is widely used in printing inks and coatings. In addition, its chemical structure contains both hydrophobic acetal and acetate groups and hydrophilic hydroxyl groups, so PVB has good adhesion to glass, metal, plastic, leather and wood. Chemical Reaction Properties Any chemical that can react with secondary alcohols will also react with PVB. In a lot of PVB applications, it's common to mix it with thermosetting resins. This helps to strengthen the hydroxyl groups in PVB, making it more resistant to chemicals, solvents, and water. Depending on the type of thermosetting resin and how much you mix with PVB, you can create coatings with different features like hardness, toughness, and impact resistance. Safety Properties Pure PVB is non-toxic and harmless to the human body. In addition, ethyl acetate or alcohol can be used as solvents, so PVB is widely used in printing inks for food containers and plastic packaging in Europe and the United States. Storability Properties As long as PVB is not in direct contact with water, it can be stored for two years without affecting its quality; PVB needs to be stored in a dry and cool place and avoid direct sunlight. Avoid heavy pressure when storing PVB. Solubility Properties PVB dissolves in alcohol, ketones, esters, and some other solvents. The solubility in various solvents varies according to the functional group composition of PVB itself. Please refer to CCP PVB Solvent Solubility Table. Basically, alcohol solvents mix well, but methanol doesn’t blend as easily with substances that have a lot of acetal groups. The more acetal groups there are, the easier it is to mix with ketone and ester solvents. PVB has good solubility in alcohol ether solvents, like Cellosolve. It only partly mixes with aromatic solvents such as xylene and toluene, and it won’t mix at all with hydrocarbon solvents.   PVB (such as Changchun PVB) has good film-forming properties. The coating formed by PVB (Butvar B-72 & PVB WWW-A-20) has excellent properties such as high transparency, elasticity, toughness, strength resistance, oil resistance, flexibility and low-temperature impact resistance.   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 452 Properties Properties   Polyvinyl alcohol (PVOH, PVOH452&Alcotex 45) is a water-soluble synthetic polymer. PVOH has excellent film-forming and adhesive properties, making it an ideal material for the production of films and adhesives. PVOH also has strong resistance to oil, grease and organic solvents. It is commonly used in packaging, textiles and coatings for a variety of purposes.   Applications of Polyvinyl Alcohol 452   PVOH is a versatile polymer that can be widely used in different industries.In the food industry, it's popular as a packaging material because it does a great job at keeping moisture and oxygen out. PVOH is a very popular material. The film formed by PVOH can also be used as an adhesive layer for different types of films, making it an important component of flexible packaging. In addition, PVOH can also be used in the production of laundry detergent pods. It is a water-soluble packaging material that dissolves in water during the washing process.     In the medical field, PVOH is used to create water-soluble films for blister packs. These films help keep medicines safe from moisture and spoilage. It can also be used in medical textiles and surgical dressings. PVOH works as a binder for making gypsum-based products. It's really handy in construction because it makes the final products stick better and last longer. In farming, PVOH is used for coating seeds and in fertilizers that gradually release nutrients.     Recyclability of Polyvinyl Alcohol 452   Polyvinyl alcohol (PVOH, PVOH452&Alcotex 45) is a recyclable material, and the recycling process involves dissolving it in water to break down its molecular structure, making it easier to separate from any impurities. The resulting solution is filtered and the PVOH is then regenerated by removing the water from the solution. The regenerated PVOH can be used to produce a variety of products such as compostable bags, water-soluble films, and adhesives.   Recycling PVOH is essential to reduce the amount of plastic waste in the environment and conserve resources. In addition, PVOH is biodegradable, which means that it can be broken down by microorganisms and eventually decomposed into natural compounds. Therefore, recycling PVOH not only reduces waste, but also reduces the amount of plastic waste in landfills and oceans, which has a positive impact on the environment.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com  

Ethylene-VinylAlcohol Copolymer (EVOH) resin provides a superior barrier against oxygen permeation, exhibiting performance up to four orders of magnitude greater than conventional polyethylene. Due to its excellent barrier properties, formability, and environmental friendliness, it is widely used in high-end new material fields such as automotive fuel tanks, films, food containers, and underfloor heating pipes. When it comes to food packaging, EVOH really helps keep food fresh and flavorful for a long time, sometimes even years, without needing preservatives. EVOH( EW-3201&EVAL F105B)is made bycombining ethylene and vinyl alcohol.     Applications    1.Packaging EVOH is often used with other materials for packaging since it's such a strong barrier: Food & Beverage: It’s used for items like milk, juice, seafood, and other things that spoil quickly. For example, Chinese seafood exporters use five-layer vacuum-sealed films made of PE, EVOH, and PA. Non-Food: You’ll find it in chemicals, cosmetics, pharmaceuticals, and electronics packaging.   2. Automotive Fuel Tanks: EVOH mixed with HDPE makes lightweight and affordable plastic fuel tanks. Structure : Outer layer (HDPE) → Recycled layer → Adhesive layer (LLDPE) → Barrier layer (EVOH) → Adhesive layer (LLDPE) → Inner layer (HDPE). Fuel Lines: PA-EVOH composite tubes replace metal pipes, aiding vehicle lightweighting.       3. Medical Selective Permeable Membranes: Sterilized via radiation (e.g., EVOH hollow fibers for dialysis). Artificial Kidneys: Hollow-fiber membranes for blood purification. Drug Delivery: EVOH-coated polymers for controlled-release medications. Biomedical Implants: Blends with corn starch or cellulose acetate for bone substitutes and tissue repair.   4. Construction Heating Pipes: EVOH’s oxygen barrier prevents corrosion in heating systems. Types: 3-layer (external barrier) and 5-layer (internal barrier) pipes, both using EVOH.   5. Other Uses Textiles: Heat-sealing adhesives with superior wash resistance for apparel. Hydrogen Storage: EVOH-modified hydrogen tank liners maintain elasticity and barrier performance even at low temperatures.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com