PVB WWW-A-20

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

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

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