Polyvinyl alcohol(PVOH, PVA, or PVAl) is a water- soluble synthetic polymer.
Polyvinyl alcohol has excellent film forming,emulsifing 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 dissolves quickly.
PVA is an atactic material but exhibits crystallinity as the hydroxyl groups are small enough to fit into the lattice without disrupting it.
- Paper adhesive with boric acid in spiral tube winding and solid board production
- Thickener, modifier, in polyvinyl acetate glues
- Textile sizing agent
- As a water-soluble film useful for packaging. An example is the envelope containing laundry detergent in "liqui-tabs".
- Feminine hygiene and adult incontinence products as a biodegradable plastic backing sheet.
- Carbon dioxide barrier in polyethylene terephalate (PET) bottles
- As a film used in the water transfer printing process
- PVA fiber, as reinforcement in concrete
- As a surfactant for the formation of polymer encapsulated nanobeads
- Used in protective chemical-resistant gloves
- When doped with iodine, PVA can be used to polarize light
- As agent in artificial Tears for treatment of dry eye.