(1) Solubility: hydrophilic, easily soluble in water (generally dissolved in hot water above 90℃), insoluble in almost all organic solvents.
(2) Film formation: easy to form film, the mechanical properties of the film is excellent. In addition to H2O, PVA film has excellent resistance to H2, N2, O2 and other gases.
(3) Adhesion: good adhesion with hydrophilic cellulose, paper, etc.
(4) Thermal stability: when the 17-99 flake is heated to more than 130℃, the appearance gradually changes. Fully hydrolysed PVA begins to melt at about 230 ° C and decompose above 200 ° C.
(5) Solvent resistance: PVA has strong resistance to weak acid and weak alkali, and has good oil resistance.
(6) Reactivity: with excellent cross-linking reactivity, can cross-link with boric acid, acetal reaction with formaldehyde, acetaldehyde, etc., the product has water resistance.
(1) Fiber processing industry: staple yarn, long yarn and post processing fields.
(2) Film processing industry: using different processes to produce water-soluble films.
(3) Coated mould industry: base cloth shaping and enhancement.
(4) Paper processing industry: surface sizing.
(5) Adhesive industry: rewet bonding.
(6) Stabilizer industry: vinyl acetate emulsion polymerization.
(7) Others: cosmetics, pharmaceutical agents, additives for building materials, temporary protective film and other fields.
Old Standard | New Standard | Item | |||||
20-88 | 088-35 | Hydrolysis(mol%) | Viscosity | Volatile | Ash | PH | Purity |
86.5-89.0 | 29.0-40.0 | ≤5.0 | ≤0.5 | 5~7 | ≥93.5 | ||