Market application:
Name: Polyvinyl alcohol
Abbreviation: PVA
The molecular composition and structure:
( CH3CHCOOCH3 )x ( CH2CHOH )y
in which: x + y indicates the degree of polymerization, y / (x + y) that alcoholysis degree
The physical and chemical properties:
Solubility:
The Polyvinyl alcohol powder can be dissolved in water. PVA with Less than 95%alcoholysis degree can be dissolved in water at room temperature and PVA with more than 99.5% alcoholysis degree can only be dissolved in hot water above 95℃.
Thermal Stability:
The heat can make PVA soften and there is no significant change below 40℃ but 160 ℃ or more, for a long time heated ,it will gradually be colored .when 220℃ above it is decomposed to produce water, acetic acid, acetaldehyde and propylene aldehyde.
Chemical Resistance:
PVA is almost free from weak acid, weak base, or the impact of organic solvents, oil is very high.
Storage Stability:
PVA is a low viscosity of the polymer, the solution is stable at room temperature. Aqueous solution in the storage process is not degenerate.
Film:
As the high adhesion between PVA molecular, PVA is easy to form a colorless, transparent film with good mechanical strength, smooth surface without tacky, and good solvent resistance. Monolayer has excellent light-admitting quality , high permeability rate, no charged, no absorption and good printing character .
The Chemical Property:
PVA can be seen as a linear polymer with a hydroxyl polymer. Hydroxyl of molecules which has high activity can be a typical chemical reaction of low-alcohol, such as esterification, etherification, acetal, etc and can also react with a number of inorganic compounds or organic compounds.