Name | Poly(vinyl formal) |
Synonyms | PVF PVFO FORMVAR RESIN Poly(vinyl formal) vinyl formal homopolymer polyvinylformalstaplefiber Vinylacetate,polymerwithformaldehyde |
CAS | 9003-33-2 |
InChI | InChI=1/C2H4O.CH2O/c1-2-3;1-2/h2-3H,1H2;1H2 |
Molecular Formula | C5H8O2 |
Molar Mass | 100.11582 |
Density | 1.23 g/mL at 25 °C (lit.) |
Melting Point | 85-120 °C |
Boling Point | 23.5°C at 760 mmHg |
Solubility | Soluble in acetone, chloroform, dioxane, THF |
Vapor Presure | 812mmHg at 25°C |
Appearance | powder |
Specific Gravity | 1.23 |
Refractive Index | n20/D 1.502 |
Physical and Chemical Properties | PVDF for short. Polyvinyl alcohol and formaldehyde from the role of polymer compounds. Microstrip grass yellow solid. Thermoplastic. Density 1.2. The softening point was about 190 °c. The thermal deformation temperature is 65 to 75 degrees C. Water absorption of about 1%. Soluble in acetone, chlorinated hydrocarbons, acetic acid, phenols. Mainly used for the manufacture of wear-resistant high-strength enamel coating and metal, wood, rubber, glass laminated plastic adhesive between, as the intermediate layer of laminated plastic and the manufacture of high impact strength, compression of the elastic modulus of foam plastics. |
Use | Mainly used in the manufacture of wear-resistant high-strength enameled wire coating and metal, wood, rubber, glass laminated plastic adhesive between |
WGK Germany | 3 |
TSCA | Yes |
EPA chemical substance information | information provided by: ofmpeb.epa.gov (external link) |
Use | The Nature and Use of polyvinyl formal, with the polyvinyl alcohol raw materials, the production method and the degree of acetalization vary greatly. The most important industrial use is the production of vinylon fiber. polyvinyl formal can be used as foaming agent, abrasive material, adhesive, electrical insulation material and so on in addition to Vinylon fiber. for the preparation of phenolic-acetal adhesive, such as iron anchor 20l, 202, 203 adhesive; Mainly used in the manufacture of high-strength enamel wire coating and metal, wood, rubber, the adhesive between glass laminated plastics, etc.; Can be pure spinning, can also be blended with a variety of fiber processing materials, industrial canvas, rope and so on. mainly used in the manufacture of wear-resistant high-strength enameled wire coating and metal, wood, rubber, glass laminated plastic adhesive between can be pure spinning, can also be blended with a variety of fiber processing materials, industrial canvas, rope, etc. |
Application history | in the early 30's of 20th century, WAMK chemical company of Germany first prepared polyvinyl alcohol fiber. In 1939, the fiber was treated with formaldehyde by Ishiko sakurata, yizawa, U. K., and Li Shengji of Korea to produce hot-water-resistant Polyvinyl formal fiber, which was manufactured by the Japan cangfu Rayon Company (now kollori company) in 1950. Industrial production plant will be built. In 1984, the world production of polyvinyl alcohol fiber was 94KT. In the early 60 s, the water-soluble polyvinyl alcohol fibers produced by the Japanese Vinylon company and the company were put on the market. Chinese trade name of polyvinyl formal fiber, also known as vinylon. Because it dissolves in water, it cannot be used as a textile fiber and is mainly used as a surgical suture. In 1939, the heat treatment and acetalization method of polyvinyl alcohol (PVA) was successfully developed by Ishiko sakurata and others in Japan, and vinylon became a fiber with good heat resistance and water resistance. The countries producing vinylon in the world are mainly China, Japan, Korea and so on. The properties of vinylon were similar to cotton, and its strength and wear resistance were better than cotton. It has good durability, moisture absorption, heat retention, abrasion resistance and resistance to sunlight; The main disadvantages are poor hot water resistance, poor elasticity, poor dyeing, low mechanical properties at high temperature. A large number of vinylon used with cotton, viscose fiber or other fiber blend, can also be pure spinning, used to make a coat, an undergarment, a shirt, a shirt and a sport shirt, and a work clothes; Can also make canvas, cable, fishing net, packaging materials and filter materials. |
synthesis process | the manufacture of vinylon fiber in industry is to dissolve polyvinyl alcohol in water to prepare about 15% aqueous solution, through a spinneret with a pore diameter of about 0.07, the fiber is prepared in a saturated sodium sulfate aqueous solution coagulation bath, and then subjected to stretching and heat treatment to improve the strength and hot water resistance; Then in the presence of catalyst sulfuric acid, acetalization reaction is carried out with formaldehyde, the temperature is about 70 deg C, the time is 20~30 minutes, after washing, oil to get Vinylon fiber. Vinylon fiber has short fibers, tow and filament and other varieties, of which the cotton staple fiber and tow is the most common. when the polyvinyl alcohol is heat-treated at 200 ° C. At a low temperature, the crystallinity is 50% or more. Low crystallinity is easily soluble in water, high crystallinity is not soluble in water, by 200 deg C heat treatment of polyvinyl alcohol solid, even in hot water at 80 deg C is insoluble. Vinylon fiber production, is the use of polyvinyl alcohol fiber extension heat treatment, so that the crystallinity increased after formaldehyde reaction. After moderate formaldehyde, there is a small amount of cross-linking, into hot water insoluble, also does not shrink the fiber. |
production method | polyvinyl formal is obtained by acetalization of polyvinyl alcohol and formaldehyde in the presence of an acidic catalyst, alternatively, polyvinyl acetate is dissolved in acetic acid or alcohol and hydrolyzed and acetalized with formaldehyde under the action of an acidic catalyst. |