PVAc

Polyvinyl alcohol (PVA) has excellent film forming, emulsifying, and adhesive properties. It is also resistant to oil, grease and solvent. It is odorless and nontoxic. It has high tensile strength and flexibility, as well as high oxygen and aroma barrier properties. However these properties are dependent on humidity, in other words, with higher humidity more water is absorbed. The water, which acts as a plasticiser, will then reduce its tensile strength, but increase its elongation and tear strength. PVA is fully degradable and is a quick dissolver. PVA has a melting point of 230°C and 180–190°C for the fully hydrolysed and partially hydrolysed grades, respectively. It decomposes rapidly above 200°C as it can undergo pyrolysis at high temperatures.

Some other uses of polyvinyl alcohol include:
Adhesive and thickener material in latex paints, paper coatings, release liner, hairsprays, shampoos and glues.
Textile sizing agent
Carbon dioxide barrier in polyethylene terephthalate (PET) bottles
Carotid phantoms for use as synthetic vessels in doppler flow testing
Movie practical effect and children's play putty or slime when combined with borax
Feminine hygiene and adult incontinence products as a biodegradable plastic backing sheet.
As a mold release because materials such as epoxy do not stick to it
As a water-soluble film useful for packaging.
As fiber reinforcement in concrete
As a surfactant for the formation of polymer encapsulated nanobeads
Used with polyvinyl acetate to make Elmer's glue
Used in eye drops and hard contact lens solution as a lubricant
Used in protective chemical-resistant gloves
Used as a fixative for specimen collection, especially stool samples
When doped with iodine, PVA can be used to polarize light
As an embolization agent in medical procedures
As a film used in the water transfer printing process

Fishing:
PVA is widely used in freshwater sport fishing. Small bags made from PVA are filled with dry or oil based bait and attached to the hook, or the baited hook is placed inside the bag and cast into the water. When the bag lands on the lake or river bottom it breaks down, leaving the hook bait surrounded by ground bait, pellets etc. This method helps attract fish to the hook bait.

Anglers also use string made of PVA for the purpose of making temporary attachments. For example, holding a length of line in a coil, that might otherwise tangle while the cast is made.

Production:
Consumption of polyvinyl alcohol was over one million metric tons in 2006. Larger producers include Kuraray (Japan and Europe) and Sekisui Specialty Chemicals (USA) but mainland China has installed a number of very large production facilities in the past decade and currently accounts for 45% of world capactity.

Preparation:
Unlike most vinyl polymers, PVA is not prepared by polymerization of the corresponding monomer. The monomer, vinyl alcohol, almost exclusively exists as the tautomeric form, acetaldehyde. PVA instead is prepared by partial or complete hydrolysis of polyvinyl acetate to remove acetate groups.

ORIGIN: TAIWAN
PURITY: 45%

PRICE INCOTERM: FOB
PACKING: 50 KG PLASTIC DRUM.
SHIPMENT: FROM TAIPEI / TAICHUNG / KAOHSIUNG PORT, TAIWAN

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