Polyvinyl acetal, English name: Vinylec K, CAS: 63148-64-1, chemical formula: C3H6O2, density: 1.253g/mLat 20 ° C, flash point: 16 ° C, refractive index: n20/D 1.445, MSDS.

Polyvinyl acetal is a condensate of polyvinyl alcohol and formaldehyde, which is a white or yellowish amorphous solid. Its softening point is higher than that of the same acetal (140~ 150 ° C), its strength, rigidity and hardness are larger, and it has good bonding properties; it has good oil resistance, electrical insulation, etc. It has good water resistance, alkali resistance, acid resistance; it can be soluble in solvents such as formic acid, acetic acid, furfural, phenols, and azobenzene.
 

Polyvinyl acetal is obtained by dissolving polyvinyl alcohol in water and adding formaldehyde to react. Alternatively, polyvinyl acetate is dissolved in acetic acid or alcohol, and hydrolyzed and acetalized with formaldehyde under the catalysis of sulfuric acid or hydrochloric acid to generate polyvinyl acetal in one step. For example, 100 parts of polyvinyl acetate, 200 parts of acetic acid, and 70 parts of water are heated to 70 ° C, completely dissolved by stirring, and then 60 parts of formaldehyde (40%) and 4 parts of sulfuric acid are added, reacted at 70 ° C for 24 hours, then neutralized with ammonium acetate, and water is added to precipitate polyvinyl acetal. After washing and drying, the product is obtained.

The largest use of polyvinyl acetal is as an insulating enameled wire coating. Generally, it is mixed with less than 20% soluble thermosetting phenolic resin. It is a heat-resistant, water-resistant, transformer oil-resistant and wear-resistant insulating paint. It can also be used as a surface coating for paper, artificial leather, etc., and an inner coating for storage tanks. In addition, it can also be used as an adhesive mixed with phenolic resin for bonding between various metals, wood, rubber, glass laminates, and for bonding aircraft parts in the aviation industry. Mixed with phenol, it can be plasticized and extruded for cable insulation coating and making foam plastics. The foamed products of polyvinyl acetal are very hard when dried, become swollen once they adhere to water, and maintain their soft-to-touch elastomer state, so they are often used in powder wipes for cosmetics, cleaning products for automobiles, bathing, photographic negatives and food containers. It can also be used in printing plates, medical and filter materials. It can also be used as a foam with high impact strength and high compressive elastic modulus. This plastic is used in the middle layer of laminated plastics and is widely used in the aviation industry.

The raw materials for the production of resins have different degrees of irritation to the skin and mucous membranes of the human body, which can cause allergic reactions and inflammation of the skin; at the same time, attention should also be paid to the harm of resin dust to the human body. Long-term inhalation of high-concentration resin dust can cause lung diseases. Most resins have common dangerous characteristics: in case of open flames, high temperatures are flammable, and contact with oxidants can cause combustion hazards. Therefore, operators should improve the operating environment, consciously divide the operating area from the non-operating area, automate and seal it as much as possible, and install ventilation facilities. Paper-plastic composite bag packaging, 25kg/bag, stored in a cool, ventilated and dry place to prevent sun and rain, away from fire sources, can be transported as non-dangerous goods.

Polyvinyl formaldehyde can be processed on a hot roller press. It is mixed with rubber in a certain proportion and can be injected and extruded into mechanical products and electrical products with high impact strength and high elastic modulus. Due to its high strength, good heat resistance, and good solvent resistance, wear resistance and excellent dielectric properties, polyvinyl formaldehyde is an excellent material for insulating paints and is also commonly used as an adhesive and coating.

63148-64-1 - nature

Trusted Data

Polyvinyl acetal is a condensate of polyvinyl alcohol and formaldehyde, which is a white or yellowish amorphous solid. Its softening point is higher than that of the same acetal (140~ 150 ° C), its strength, rigidity and hardness are larger, and it has good bonding properties; it has good oil resistance, electrical insulation, etc. It has good water resistance, alkali resistance, acid resistance; it can be soluble in solvents such as formic acid, acetic acid, furfural, phenols, and azobenzene.
 

63148-64-1 - Method

Trusted Data

Polyvinyl acetal is obtained by dissolving polyvinyl alcohol in water and adding formaldehyde to react. Alternatively, polyvinyl acetate is dissolved in acetic acid or alcohol, and hydrolyzed and acetalized with formaldehyde under the catalysis of sulfuric acid or hydrochloric acid to generate polyvinyl acetal in one step. For example, 100 parts of polyvinyl acetate, 200 parts of acetic acid, and 70 parts of water are heated to 70 ° C, completely dissolved by stirring, and then 60 parts of formaldehyde (40%) and 4 parts of sulfuric acid are added, reacted at 70 ° C for 24 hours, then neutralized with ammonium acetate, and water is added to precipitate polyvinyl acetal. After washing and drying, the product is obtained.

63148-64-1 - purpose

Trusted Data

The largest use of polyvinyl acetal is as an insulating enameled wire coating. Generally, it is mixed with less than 20% soluble thermosetting phenolic resin. It is a heat-resistant, water-resistant, transformer oil-resistant and wear-resistant insulating paint. It can also be used as a surface coating for paper, artificial leather, etc., and an inner coating for storage tanks. In addition, it can also be used as an adhesive mixed with phenolic resin for bonding between various metals, wood, rubber, glass laminates, and for bonding aircraft parts in the aviation industry. Mixed with phenol, it can be plasticized and extruded for cable insulation coating and making foam plastics. The foamed products of polyvinyl acetal are very hard when dried, become swollen once they adhere to water, and maintain their soft-to-touch elastomer state, so they are often used in powder wipes for cosmetics, cleaning products for automobiles, bathing, photographic negatives and food containers. It can also be used in printing plates, medical and filter materials. It can also be used as a foam with high impact strength and high compressive elastic modulus. This plastic is used in the middle layer of laminated plastics and is widely used in the aviation industry.

63148-64-1 - security

Trusted Data

The raw materials for the production of resins have different degrees of irritation to the skin and mucous membranes of the human body, which can cause allergic reactions and inflammation of the skin; at the same time, attention should also be paid to the harm of resin dust to the human body. Long-term inhalation of high-concentration resin dust can cause lung diseases. Most resins have common dangerous characteristics: in case of open flames, high temperatures are flammable, and contact with oxidants can cause combustion hazards. Therefore, operators should improve the operating environment, consciously divide the operating area from the non-operating area, automate and seal it as much as possible, and install ventilation facilities. Paper-plastic composite bag packaging, 25kg/bag, stored in a cool, ventilated and dry place to prevent sun and rain, away from fire sources, can be transported as non-dangerous goods.

63148-64-1 - Forming

Trusted Data

Polyvinyl formaldehyde can be processed on a hot roller press. It is mixed with rubber in a certain proportion and can be injected and extruded into mechanical products and electrical products with high impact strength and high elastic modulus. Due to its high strength, good heat resistance, and good solvent resistance, wear resistance and excellent dielectric properties, polyvinyl formaldehyde is an excellent material for insulating paints and is also commonly used as an adhesive and coating.