Glue PVA - composition
If you need something to glue, first of all remember the most common glue PVA. It is available in every home and office, it is used not only for gluing conventional paper, but also for construction and industry. And this is due to its simple composition, which makes it possible to change the application by introducing special additives.
A bit of history
In the distant 1912, the German Klatt managed to get vinyl acetate from acetylene gas. The new substance became sticky as a result of the polymerization. But just before the Second World War, the American Farben set up an industrial production of PVA glue.
Four years later, a Korean, conducting independent research, receives a vinalon, based on polyvinyl alcohol. So PVA glue, the price of which is less than many other glue compounds, has spread around the world.
In the territory of the former Soviet Union, mass production of PVA began in the early seventies of the twentieth century in Severodonetsk (Lugansk region). Our grandmothers still remember that before in schools in labor lessons for gluing paper used glue with an unusual name "gum arabic". And in the difficult post-war years, the glue of the house was prepared from starch or boiled potatoes.
And now we can’t imagine how to do without PVA glue.
Glue PVA: characteristics
This remarkable and habitual means has many valuable properties. Its adhesive capacity is 450 N / m. Due to its elasticity and uniformity, it is applied with a thin layer, which becomes invisible after drying. Paper, glued PVA, you can easily bend, after drying it does not break.
A huge plus is non-toxicity and incombustibility, which allows it to be used by children in class and at home. The slight odor, which is released when using glue, is harmless. All types of glue, except PVA-K (clerical), can withstand fourfold freezing without loss of properties. If necessary, it is diluted with water or other solvents, for example acetone. The drying time depends on the thickness of the layer and does not exceed 24 hours.
Its liquid base allows you to enter various additives in the PVA glue, the composition of which changes in this way in the right direction. So were developed new varieties of the usual glue.
Varieties of PVA
Thanks to additives, the field of application of PVA glue has expanded.
We list the main areas of use:
- domestic use (pasting stationery);
- use when repairing (gluing wallpaper, linoleum);
- installation of ceramic tiles;
- use in construction as additives.
Description of types of glue
Stationery glue PVA, the composition of which does not contain toxic additives, is used for gluing paper, children's art. Due to the absence of other solvents, other than water, it is harmless to children, it can be used indoors without hoods.
The most common grade of PVA is universal. It has a wide scope of application. They can glue porcelain, glass and paper. It is added to the primer, putty when repairing the premises, in order to strengthen the binding properties.
Household PVA is used for pasting wallpaper, thick paper. It has a high frost resistance.
Glue PVA super has a viscous consistency due to plasticizers, therefore it is used for fixing tiles, plastic, metal. Its main application is the construction industry.
Glue PVA joinery has increased moisture resistance and is used for joining wooden products.
Another type of popular glue is the Moment PVA. It is characterized by its property of instant gluing of surfaces without force, pressing. It can be used for fixing laminate, parquet and other surfaces.
Features of some varieties of PVA
Construction PVA is used not only as an independent adhesive compound, but also as an additive to various building materials. The correct name for the construction adhesive is a homopolymer polyvinyl acetate dispersion. Due to the density of the composition, the construction adhesive is applied with a spatula. And the surfaces to be glued must be thoroughly cleaned from dust and degreased.
Glue PVA, the composition of which includes a plasticizer, should not cool below zero degrees, otherwise it loses its properties. At the same time, glue, which does not contain such additives, is able to withstand frost of forty degrees, without losing its adhesive properties after defrosting. If a dry film forms on the surface of the glue mass, it must be removed and the mixture mixed thoroughly. To prevent the glue from drying out, it is stored in a carefully closed container.
Glue PVA: composition
Consider the main components that are added to the glue to change its adhesive properties. This raw material is added at the production stage and is divided into the following groups:
The ratio of the above components and gives the necessary properties of different types of glue.
Adhesives, which include starch and resin, give the composition strength when combined.
As solvents, acetone, gasoline and others are used. Strengthening water resistance and heat resistance, they reduce the strength of the adhesive layer. Therefore, the content of solvents in PVA is minimal.
So-called plasticizers give flexibility to glue joints. Therefore, paper glued PVA, you can easily bend, not breaking the connection. Plasticizers include glycerin, camphor oil.
To improve the strength of the adhesive mass, fillers are added: kaolin, talc, chalk.
To reduce the period of hardening and solidification, use small additions of glass, porcelain or metal.
To increase the shelf life of the adhesive, stabilizers are added to its composition, which include styrene inhibitors and various nitro compounds.
Glue PVA, the price of which depends on the purpose and availability of certain components, is still recognized as the cheapest and affordable. Construction adhesive costs from 26 rubles per kilogram. It is more suitable for gluing wallpapers. Universal adhesive PVA marks "Rainbow", "Bolars" will cost more - from 65 rubles per kilogram.
Original ways of using PVA
In addition to the usual methods of using PVA glue for gluing paper or during repairs, craftsmen find it more original application.
For example, by combining gouache and PVA, you can draw on canvas or other surfaces. It turns out a wonderful alternative to expensive oil or acrylic paints. Thanks to the glue, the gouache lies well on the material, it lasts a long time. If the result is not liked, then everything is easily washed off, and you can start again.
Women use glue for manicure. It can be applied to the nails as a base for varnish with sparkles. Due to its non-toxicity, it is harmless to the nails and at the same time is easily removed without the use of solvents.
If you apply glue to the cuticle around the nail, then you can not be afraid that the varnish gets on the skin. A strip of glue with residual varnish is instantly removed after drying.
For the storage of PVA glue, whose composition complements volatile solvents, closed containers are used, which are kept at a temperature of from five to ten degrees Celsius.