(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) Adhesive industry: paper, paper tube bonding.
(2) Construction industry: acetalated products are used for building glue, interior and exterior wall coatings, adhesives.
(3) C eramic industry: aluminum ball binder, ceramic binder, etc.
(4) Stabilizer industry: stabilizer for vinyl acetate emulsion polymerization and urea-formaldehyde adhesive viscosification.
Old Standard Grades Name | New Standard Grades Name | Item | |||||
Hydrolysis (mol%) | Viscosity (mpa.s) | Volatile (%≤) | Ash (%≤) | PH (Value) | Purity (% ≥) | ||
26-99 | 100-70 | 99.0-100 | 78.0-85.0 | ≤5.0 | ≤0.7 | 5~7 | ≥93.5 |