Basic information of PVA

CAS No.: 9002-89-5

Molecular formula: [C2H4O]n

1. Solubility

PVA is soluble in water, the higher the temperature, the greater the solubility, but almost insoluble in organic solvents. The solubility of PVA and polymerization degree and alcoholysis degree change. PVA dissolved quickly and alcoholysis degree of polymerization and alcoholysis, complete and high degree of polymerization PVA slow dissolution. The general rule, influence on the solubility of PVA, alcoholysis degree is greater than the degree of polymerization. PVA dissolution process is carried out in stages, namely: affinity wetting a swelling infinite swelling dissolving. The film of PVA film, the film of good mechanical properties, the tensile strength of the film increased with increasing degree of alcoholysis, degree of polymerization. Adhesion of PVA with hydrophilic cellulose has good adhesion. In general, the degree of polymerization and alcoholysis degree is higher, the stronger the bonding strength.

2. Thermal stability

PVA powder is heated to 100℃, the appearance of change gradually. PVA alcoholysis begins to melt at 190℃, 200℃come to decomposition. Complete alcoholysis PVA began to melt at 230℃, 240℃ of decomposition. Pyrolysis experiments show that: the lower the degree of polymerization, the faster the weight reduction; alcoholysis degree is higher, the shorter the time of decomposition.

3. Uses and Application

The PVA has unique and strong adhesive, coating flexibility, smoothness, oil resistance, solvent resistance, protective colloid, gas denial, wear resistance and the special treatment of water resistance, so in addition to making the fiber raw material, is widely used for production of coatings, adhesives, paper processing agent, emulsifying agent, dispersing agent, film and other products, the scope of application throughout the textile, food, medicine, construction, timber processing, papermaking, printing, agriculture, steel and macromolecule chemical industry.