Polyvinyl alcohol is a synthetic polymer that is readily soluble in water.It was obtained in 1924 by two chemists - Gonelem and Germany - with the help of the saponification reaction.Physical properties
Polyvinyl alcohol - is a white powder having the ability to form a film.This polymer is very strong and flexible, but since these depend on the quality of moisture (it absorbs fluid), the tensile strength decreases, and a certain degree of humidity there is a greater ductility.It has a hygroscopic, readily soluble (mainly water).In organic solvents such as fats and oils, it is not capable to dissolve.When using this substance has no toxic effects, and therefore can be considered harmless.
Preparation
alcohol PVA or PVA obtained by hydrolysis of polyvinyl acetate and alcoholysis or produced in the form of granules or powder.Upon receipt of PVA uses a variety of technological methods, from simple to fairly complex and time-consuming.
Polyvinyl alcohol - use
PVA is widely used today.He can play the role of a thickener in the manufacture of adhesives and shampoos, it can produce a latex material.It is successfully used to restore the restorers of paintings.Due to its hygroscopic properties, it is widely used in the creation of hygiene products.All kinds of diapers, tampons and pads are made using PVA.Do not forget the polyvinyl alcohol, and food producers.It is used as an emulsifier in the production of mayonnaise, sauces, ketchup and other food products, and is also used as a flavor enhancer confectionery.
Modern medicine also has adopted some of the properties of PVA.It is used in the manufacture of certain medicines, before subjecting it thoroughly cleaned of impurities.Ophthalmologists polyvinyl alcohol used for the preparation of eye drops, and as a lubricant for contact lenses.Even oncologists have been used PVA in the treatment of cancer.In particular, it is necessary to perform non-surgical embolization procedures.And it is not the whole range of applications of polyvinyl alcohol in medicine.
In the textile industry PVA is used to dissipate static electricity, and in paper - recycling of waste paper.Additionally, it is an indispensable component in the production of pulp.Polyvinyl alcohol is needed builders and metallurgists, tanners and manufacturers of paints and varnishes.All plants producing artificial fibers are used for the manufacture of PVA which gives it strength by the process of sizing fibers.
even a science of microbiology has used PVA in the immobilization of enzymes and cells.Polyvinyl alcohol has found application in the printing industry, in particular screen printing.In this field it is used as a polymer layer for the copying process.It can be used also as a packaging or protective material in the production of coating components due to the fact that a layer of PVA is easily removed.
enterprises manufacturing and applying the mold is also used with success this polymer.Today, PVA is becoming more common in the economy.It is available at a price easily conveyed (usually in plastic bags packed in paper bags) in the closed transport avoid wetting.Since the polyvinyl alcohol is flammable, it is necessary to comply with the safety regulations in their storage and handling.
