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Gloves are the most commonly used protective tools in the laboratory besides goggles. There are many types of gloves, and different gloves have different uses.     1. Natural rubber (latex) Latex gloves, made from natural rubber, typically lack a lining and are available in both clean and sterile versions. These gloves can provide effective protection against alkalis, alcohols, and a variety of chemical dilution aqueous solutions, and can better prevent corrosion from aldehydes and ketones.   2. Polyvinyl chloride (PVC) gloves The gloves do not contain allergens, are powder-free, have low dust generation, low ion content, strong chemical corrosion resistance, can protect almost all chemical hazardous substances, and also have anti-static properties. Thickened and treated surfaces (such as fleece surfaces) can also prevent general mechanical wear, and thickened types can also prevent cold, with an operating temperature of -4℃ to 66℃. Can be used in a dust-free environment. PVC gloves grading standards: Grade A products, no holes on the surface of the gloves (PVC gloves with powder), uniform powder, no obvious powder, transparent milky white color, no obvious ink spots, no impurities, and the size and physical properties of each part meet customer requirements. Grade B products, slight stains, 3 small black spots (1mm≤diameter≤2mm), or a large number of small black spots (diameter≤1mm) (diameter>5), deformation, impurities (diameter≤1mm), slightly yellow color, serious nail marks, cracks, and the size and physical properties of each part do not meet the requirements.   3. PE gloves PE gloves are disposable gloves made of polyethylene. These gloves are waterproof, oil-proof, anti-bacterial, and resistant to acids and bases. Note: PE gloves are safe to use with food and are non-toxic. It is better to keep PVC gloves away from food, especially if it's hot.     4. Nitrile rubber gloves Nitrile rubber gloves are usually divided into disposable gloves, medium-duty unlined gloves and light-duty lined gloves. These gloves can prevent erosion by grease (including animal fat), xylene, polyethylene and aliphatic solvents; they can also prevent most pesticide formulations and are often used in the use of biological components and other chemicals. Nitrile rubber gloves do not contain protein, amino compounds and other harmful substances, and rarely cause allergies. They are silicone-free and have certain antistatic properties, which are suitable for the production needs of the electronics industry. They have low surface chemical residues, low ion content and small particle content, and are suitable for strict clean room environments.   5. Neoprene gloves Similar to the comfort of natural rubber, neoprene gloves are resistant to light, aging, flexing, acid and alkali, ozone, combustion, heat and oil.   6. Butyl rubber gloves Butyl rubber is only used as a material for medium-sized unlined gloves and can be used for operations in glove boxes, anaerobic boxes, incubators, and operating boxes; it has super durability against fluoric acid, aqua regia, nitric acid, strong acids, strong alkalis, toluene, alcohol, etc., and is a special rubber synthetic resistant liquid gloves.   7. Polyvinyl alcohol (PVA) gloves Polyvinyl alcohol (PVA) can be used as a material for medium-sized lined gloves, so this type of gloves can provide a high level of protection and corrosion resistance against a variety of organic chemicals, such as aliphatic, aromatic hydrocarbons, chlorinated solvents, fluorocarbons and most ketones (except acetone), esters and ethers.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com

CR modified materials are really popular these days.  A company called Shanghai Shuangpu Rubber Anti-Corrosion Lining Co., Ltd. has rolled out a bunch of different rubber linings, like CR, CR/NR, and NBR/CR. These products are proving to be quite useful across various sectors, including chemicals, electricity, steel, mining, and water treatment. You can see more about this in Figure 1.   Interestingly, Shanghai Shuangpu Rubber Anti-Corrosion Lining Co., Ltd. has done some side-by-side tests and discovered that certain fluoroprene rubbers made locally are performing on par with similar CR products that come from Japan and Germany. This is great news for the local industry, as it shows that we’re capable of producing high-quality materials that can stand shoulder to shoulder with the best from around the world. So, whether it’s keeping things from rusting or just making tough parts for machines, these rubber linings are definitely pulling their weight in various industries.   However, there are still few varieties of domestically produced fluoroprene rubbers, and there is no low-hardness fluoroprene rubber material. The existing main varieties, such as Chloroprene Rubber CR121, Chloroprene Rubber CR232, etc., are made of fluoroprene lining rubber sheets that are relatively hard, and the pre-vulcanized rubber sheets produced are very hard, making the pasting construction difficult. Further tests show that adding a large amount of softener to the formula can reduce the hardness, but when it reaches a certain amount, it will significantly affect the bonding strength. The production test also shows that the bonding strength of the cold-adhesive adhesive produced by domestic Chloroprene Rubber CR244 is completely up to the level of foreign Denka A90 Chloroprene Rubber and Bayprene 213. However, after being applied to the steel plate and rubber plate, the bonding retention time of the adhesive coating is significantly lower than that of the adhesive made of Denka A90 Chloroprene Rubber and Bayprene 213, and it is more obviously affected by the ambient temperature and humidity, which increases the difficulty of rubber lining construction of large equipment and increases the quality risk. It can be seen that there is still a lot of room for research and improvement in the material variety and application characteristics of domestic fluoroprene.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com  

What is Neoprene? Neoprene, also known as polychloroprene, is a synthetic rubber made by the free radical polymerization of chloroprene and is used in a wide variety of applications. It was first introduced by DuPont and was used by the U.S. military during World War II the following decade. Although it is one of the earliest synthetic rubbers, it is still very popular today. Neoprene has a wide range of applications due to its strong physical properties, chemical resistance, and flame retardancy. Neoprene is typically molded by injection molding, transfer molding, or compression molding.     Properties of Neoprene Neoprene has many excellent properties that make it a widely used synthetic rubber. As with any polymer, there are some disadvantages to consider when considering using Neoprene for your application. Click here to learn more about how to choose the right type of rubber to manufacture your product.   Common Applications of Neoprene Neoprene is a very commonly used rubber polymer that has a wide range of uses. It is resistant to water, fire, ozone, sunlight, and many other chemicals, making it a very versatile material. These applications include refrigeration seals, Freon/air conditioning, engine mounts, engine coolant, oil and chemical tank linings, automotive gaskets and seals, and weather stripping.   Other examples of neoprene applications include: Water Sports(Chloroprene Rubber SN-242A). Neoprene is commonly used in wetsuits due to its waterproof and insulating properties. It is also used in a variety of equipment for scuba diving, fishing, surfing, boating, and other water sports. Everyday Use(Chloroprene Rubber SN-241). Neoprene is used in many household items we use every day, including mouse pads, smartphone cases, laptop bags, remote controls, dishwashing gloves, and even musical instruments. Face Masks(Chloroprene Rubber SN-243). During the COVID-19 pandemic, neoprene was found to be an effective material for making face masks. Since then, many manufacturers have used it to produce protective masks.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com

Polyvinyl Butyral Resin (PVB) resin has become a popular high-performance material in industrial applications due to its excellent adhesion, flexibility and chemical adjustability. Especially in the field of insulating paint and surface coating, its unique hydroxyl active group gives it excellent adhesion, cross-linking ability and compatibility with a variety of resins, which can not only meet the stringent electrical performance requirements, but also provide a strong and durable protective coating. Whether as an insulating coating for electromagnetic wires or as a key component of multifunctional surface coatings, Butvar PVB has demonstrated its cross-domain adaptability and established its long-term leading position in the industry.   Wire enamels Butvar resins ( Butvar B-98 & PVB WWW-A-20) may be used to overcoat magnet wire so that coils made from that wire can be cemented with heat or by solvent activation. Magnet wire that is coiled or formed, featuring a polyvinyl butyral coating, exhibits significant durability and flexibility. The hydroxyl functional groups within the polyvinyl butyral structure enable it to not only form crosslinks with itself but also to engage in cross-curing with phenolic or isocyanate resins. The comprehensive equilibrium of both physical and chemical characteristics has established Butvar-based overcoats as a predominant choice in the industry for an extended period.     Surface coatings Butvar resin (Butvar B-76 &  PVB WWW-A-30) can be utilized either independently or in conjunction with various resins to create effective surface coating formulations. Films which may be air dried, baked, or cured at room temperature are obtained by proper compounding. The incorporation of hydroxyl groups within the polymer structure not only facilitates effective wetting of various substrates but also provides a reactive site for chemical interaction with thermosetting resins.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com

Compatibility The compatibility of Butvar polyvinyl butyral resins (PVB) with various plasticizers, modifiers, and additional resins is extensively documented. Butvar is readily amenable to compounding with other additives to improve its physical and chemical characteristics. Plasticizers are frequently utilized to enhance flexibility across a wider temperature spectrum, as noted in Table 9.   Crosslinking agents, including Santolink phenolic and Resimene amino resins, are employed to provide superior toughness and thermal stability. The compatibility of Butvar polyvinyl butyral resins (Butvar B-98 &  PVB WWW-A-20) with other modifiers and resins is illustrated in Table 10.   Insolubilizing Reactions Numerous applications of vinyl acetal resins involve curing processes that utilize thermosetting resins to achieve the desired property balance. The free hydroxyl groups present in vinyl acetal resins serve as reactive sites for chemical interaction, allowing for the insolubilization of the resins. Generally, any chemical reagent or resinous material capable of reacting with secondary alcohols will interact with polyvinyl butyral (Butvar B-76 & WWW-A-30) to reduce its solubility. The characteristics of coatings can vary significantly depending on the type and quantity of crosslinking agents employed.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com

1 PVA (PVA 088-20 & PVA 1788) water resistance modification PVA (Polyvinyl alcohol) has very low air permeability and is a high-barrier packaging material with excellent performance. Because the molecular chain contains a large number of hydroxyl groups and has high hydrophilicity, these hydroxyl groups are easy to form hydrogen bonds with water molecules under high humidity, resulting in changes in the aggregate structure of PVA, causing its barrier properties to drop sharply. Therefore, necessary water resistance modification should be carried out on PVA to reduce the effect of humidity on the barrier properties of PVA. The mechanism of PVA water resistance modification is to cross-link PVA by adding a cross-linking agent, and completely or partially block the hydroxyl groups, which can reduce its hydrophilicity and achieve the purpose of improving water resistance. The 8511 Institute of the China Aerospace Corporation has developed a melamine resin modified liquid "868" that has no toxic side effects on the human body. "868" is a multifunctional polycondensate. When the amount added is not large, it can moderately cross-link with the hydroxyl groups in PVA, so that PVA forms a strong three-dimensional structure coating, which determines the air tightness of PVA under wet conditions and improves water resistance. This modified PVA coating liquid will not form a skin at room temperature, will not swell or fall off when in contact with water, and can be used for glue preparation and coating at room temperature.   2 PVA (PVA 100-27 & PVA 1799)water-soluble modification PVA's water solubility can be used to make water-soluble films. Water-soluble films are a new type of green and environmentally friendly packaging material, which is widely used in the packaging of various products in Europe, America, Japan and other countries. For example, pesticides, fertilizers, pigments, detergents, water treatment agents, concrete additives, detergents, chemical reagents for photography and chemical reagents for gardening care. Because the water solubility of pure PVA film cannot meet the requirement of dissolution time ≤ 300s in water at 20℃, Wen Huojiang et al. carried out Michael addition reaction with PVA and acrylamide, and then hydrolyzed and synthesized modified PVA under base catalysis. Water-soluble anionic groups were introduced into the PVA molecular chain to enhance the solubility. Water-soluble films were prepared using this as raw material, and the relationship between the amount of alkali, acrylamide and modification rate was discussed. The modification rate made a great contribution to the low-temperature rapid solubility of the prepared film within a certain range. The effect on water solubility beyond a certain range was not significant, but it would lead to excessively high costs.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com

The US International Trade Commission determined, in accordance with the Tariff Act of 1930, that the revocation of the anti-dumping duty order on certain Polyvinyl Alcohol (PVA) originating in China, Japan and South Korea imported into the United States may cause substantial damage to the US industry. In 2002, Celanese and DuPont launched anti-dumping investigations against the above countries. In 2003, the ITC decided that Japanese imports were a risk for injury, but they left out Germany. They also excluded China's Sichuan Weiye Company because it didn't meet the required standards at the time. On the other hand, they found that Shanghai Volkswagen was indeed dumping. In July and October 2003, the United States officially imposed anti-dumping duties on PVA from China, Japan and South Korea.     ITC clearly defined the "domestic similar products" of polyvinyl alcohol (PVA) in the review. According to the Tariff Act, similar products refer to products that are similar or most similar to the investigated goods in terms of characteristics and uses. The Ministry of Commerce has limited the scope of the investigation to PVA with a degree of hydrolysis exceeding 80%, while excluding 15 specific forms of PVA.   PVA is a water-soluble synthetic polymer in the form of white particles or powders, and its properties are mainly determined by the degree of hydrolysis, viscosity and molecular weight. In terms of production process, PVA is produced by hydrolysis of vinyl acetate monomers under the action of a catalyst after polymerization. In the USA, PVA is captively consumed or sold to end users primarily as an intermediate in the production of PVB, which is a plastic laminate used as an adhesive between panes of automotive safety glass or load-resistant architectural glass.  PVA is also sold to end users (and occasionally to distributors) for use in the textile and paper industries in sizing formulations(such as PVA 098-08 & PVA 1099); as a binder in adhesive and soil binding formulations（such as PVA 088-20 & PVA 1788); and as an emulsion or polymerization aid in colloidal suspensions, water-soluble films, cosmetics, and joint compounds (such as KURARAY POVAL 17-94).    Although different grades of PVA have differences in specific applications, the committee believes that all PVAs with a degree of hydrolysis exceeding 80% should be considered as the same type of product. This decision is based on three main points: first, all types of PVA share the same basic chemical makeup; second, different grades of PVA can be swapped for each other in many cases; and third, the way they are made and the materials used are pretty similar. It's important to note that while end users tend to stick to one specific grade of PVA to keep costs down, this habit doesn't change the fact that the product itself is quite uniform.   In this review, the Commission stuck with the product definition from the original investigation for two reasons: major manufacturers like Celanese and DuPont agreed with it, and the market hasn’t changed much since then. This decision also continues the Commission's position in the original investigation, that is, not to classify PVB-grade PVA into different product categories.   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com

  1.Glue for paper packaging and cardboard: efficient bonding, environmentally friendly and safe VAE adhesives suitable for cardboard packaging, film-sheet lamination, paper tube/honeycomb sponge molding, as well as envelope making and book binding. This product line has some great technical benefits. It offers strong bonding and good heat resistance for different materials, including engineering plastics like PET and PS. Plus, it cures quickly, which can help boost production efficiency. Its formula system combines diversity and safety. It not only meets the regulatory requirements of food contact materials, but also has excellent spraying suitability, ensuring stable and uniform sizing effects during high-speed production, while keeping the equipment clean and reducing maintenance frequency. Recommended products: VINNAPAS EP 706K, EP 707K; VINNAPAS EAF 67, EAF 68     2. Woodworking glue: high strength, low formaldehyde VAE adhesives are really flexible when it comes to wood processing. They are great for things like furniture, wood floors, plywood, and doors and windows.This adhesive has excellent water resistance and heat resistance, fast curing speed, and adopts innovative DPX technology to achieve a hardener-free formula. At the same time, the formaldehyde content is controlled below 5ppm, effectively solving the yellowing problem. Its excellent overall performance is particularly suitable for impregnated paper or PVC veneer. In addition, VAE adhesives can ensure that the surface of the product reaches a very high degree of flatness, and support the addition of medium to high proportions of PUD (polyurethane dispersion), providing professional and efficient bonding solutions for various wood processing needs. Recommended products: EP 706K, EP 707K, VINNAPAS EP 645     3. Textile laminating adhesive: strong and water-resistant, cost-optimized The application of VAE adhesives in the textile industry covers the efficient lamination of cloth and sponge, artificial leather and PVC veneer, providing a variety of product options, covering a wide range of needs from high viscosity to low viscosity, and can provide high solid content formulas. Its excellent water resistance and excellent wet peel strength ensure a strong and lasting bonding effect.Plus, they require less thickening agent, plasticizer, and solvent, which means you can save on costs. Most importantly, VAE has excellent compatibility with materials such as natural latex, acrylic emulsion, polyurethane emulsion and styrene-butadiene latex, making it more cost-effective in various applications. Recommended products: EP 706K, VINNAPAS EP 708, EP 645     4. Tobacco glue: high-speed production, ultra-low residue VAE emulsions are really useful in the tobacco industry, especially for various types of adhesives like cigarette glues (including overlapping, nozzle, and packaging glues) and special adhesives for fast packaging machines. One of their main benefits is that they have very low levels of formaldehyde (less than 15 ppm) and residual vinyl acetate (under 100 ppm), which meets strict health and safety rules. There’s a full range of formulas available, from low to high viscosity, and they offer options with high solid content to suit different production needs. Recommended products: VINNAPAS EP 710, VINNAPAS 756   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com

WACKER makes VINNAPAS VAE dispersions, which are polymer binders made from vinyl acetate-ethylene (VAE) copolymers. These binders help make many products work better and be more eco-friendly. WACKER is the top producer of VAE dispersions and redispersible polymer powders. You can find their products in lots of areas like coatings, tile adhesives, exterior thermal insulation systems, self-leveling screeds, interior plasters, paper coatings, and adhesives. What are VAE Copolymer Dispersions? These copolymers are created by mixing vinyl acetate, a hard monomer, with ethylene, a soft monomer, through emulsion polymerization. The ethylene adds flexibility to the VAE dispersions, so they don’t need extra plasticizers.   Great Rheological Properties VINNAPAS dispersions that use polyvinyl alcohol (PVOH) are easy to work with for many adhesive tasks, like paper and packaging (VINNAPAS 706 & VINNAPAS 710) . They’re good for different application methods too, such as roller and spray coating(VINNAPAS EP 705 A).   Reduced Migration The special makeup of the copolymer means that we don't need plasticizers or film-forming agents in products with VAE dispersions. This opens up many options for making low-migration adhesives.   Improved Workability Dispersions made with surfactants usually have better shear-thinning properties compared to those made with polyvinyl alcohol. This leads to better sticking to plastics, clearer films, more water resistance, and easier spraying, which makes it easier to work with floor adhesives. Plus, they can handle more fillers.   APEO Removal When making dispersions for adhesives, we don't need to use surfactants with APEOs (alkylphenol ethoxylates). So, VINNAPAS dispersions meet tougher environmental standards (such as VINNAPAS EP 7000).   Website: www.elephchem.com Whatsapp: (+)86 13851435272 E-mail: admin@elephchem.com

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