Polyvinyl Alcohol (PVOH)
Polyvinyl alcohol is widely used to produce water soluble films that are formed into water soluble pouches for pre-weighed fortified vitamin packages for cereals, fish bait, gel packs for laundry detergents and pre-weight packages for herbicides. Pre-weighed packages are convenient and protect workers from exposure hazards. For consumers they are an easy way to use a product without mess.
Polyvinyl alcohol’s strong film-forming and binding properties make it ideal for use to strengthen textile yarn and papers. The paper industry also uses polyvinyl alcohol to impart oil and grease resistance, as a carrier for optical brighteners and as a binder or co-binder in pigmented coatings.
The high-water solubility of films made from certain grades of polyvinyl alcohol find use in many applications where a sacrificial film is of benefit. For example, as a pre-coat on objects to which fiberglass or epoxy castings are to be supplied. In this application, castings are easily removed after curing by dissolving the film with water to release the mold.
Another growing market taking advantage of the solubility of polyvinyl alcohol films is the pharmaceutical market which is using polyvinyl alcohol to coat medicinal tablets. The aerospace and automotive industries also use it to coat products for protection during shipping. The advantage being that customers can rinse their products to remove bugs, grease or grime once received.
Dry polyvinyl alcohol is used in the manufacture of other resins such as polyvinyl butyral (PVB) or polyvinyl formal (PVF). PVB forms a water-resistant, plastic film, that is used to laminate safety glass for vehicles. PVF is commonly used to insulate wires.
Polyvinyl alcohol is biodegradable under certain microbial conditions. This makes it an attractive polymer for the formulation of barrier coatings for packaging.« Back to All Education Posts