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|Section2= |Section3= }} Poly(vinyl alcohol) (PVOH, PVA, or PVAl) is a water-soluble synthetic polymer. It has the idealized formula ()n. It is used in papermaking, textiles, and a variety of coatings. It is white (colourless) and odorless. It is sometimes supplied as beads or as solutions in water.〔 ==Uses== * Polyvinyl acetals: Polyvinyl acetals are prepared by reacting aldehydes with polyvinyl alcohol. Polyvinyl butyral (PVB) and polyvinyl formal (PVF) are examples of this family of polymers. They are prepared from polyvinyl alcohol by reaction with butyraldehyde and formaldehyde, respectively. Preparation of polyvinyl butyral is the largest use for polyvinyl alcohol in the U.S. and Western Europe. Polyvinyl alcohol is used as an emulsion polymerization aid, as protective colloid, to make polyvinyl acetate dispersions. This is the largest market application in China. In Japan its major use is vinylon fiber production.〔(SRI Consulting CEH Report Polyvinyl Alcohol ), published March 2007, abstract retrieved July 30, 2008.〕 Some other uses of polyvinyl alcohol include: * Paper adhesive with boric acid in spiral tube winding and solid board production * Thickener, modifier, in polyvinyl acetate glues * Textile sizing agent * Paper coatings, release liner * 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 terephthalate (PET) bottles * As a film used in the water transfer printing process * As a form release because materials such as epoxy do not stick to it * Movie practical effect and children's play putty or slime when combined with borax * Used in eye drops (such as artificial tears to treat dry eyes) and hard contact lens solution as a lubricant * PVA fiber, as reinforcement in concrete * Raw material to polyvinyl nitrate (PVN) an ester of nitric acid and polyvinyl alcohol. * As a surfactant for the formation of polymer encapsulated nanobeads * 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 * Carotid phantoms for use as synthetic vessels in Doppler flow testing * Used in 3D printing as support structure that can then be dissolved away. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Polyvinyl alcohol」の詳細全文を読む スポンサード リンク
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