How to glue the plastic wrap. Other gluing methods. How to weld at home

Film welding is one of the working steps that can sometimes be necessary. In many types of work, pieces of polyethylene film must be tightly connected together. Most often this is necessary for the construction of a greenhouse, greenhouse, installation of vapor barrier during construction.

For some activities, it is necessary to ensure the material is sealed in order to obtain a product. When gluing polyethylene using adhesive tape or adhesives, high-quality sealed joints will not be obtained, therefore, if necessary, to ensure a strong connection, welding is used.

There are many ways to weld polyethylene film. The operation itself is the bonding of layers of material by heating, creating a temperature convenient for melting. When the layers are compressed, a weld is formed.

Welding of polyethylene is as follows: When heated, the layers change their structure, join at the molecular level, and after cooling, a strong seam is formed.

To glue plastic wrap, the layers should be well cleaned - in case of any contamination strength characteristics are much reduced.

Foreign impurities pass into the melted mass, which violate the molecular structure in the seams.

For a high-quality connection with high strength, it is necessary to observe following conditions:

when welding the film, its pieces must be homogeneous, belonging to the same batch;
surfaces must be clean;
choose the temperature mode during operation correctly - with insufficient heating, the strength deteriorates, with excessive heating, the joint and the pre-seam area are deformed;
when heating, ensure sufficient compression.

In order to bond the PVC foil properly, the edges of the material must not be re-welded. If it is necessary to perform such an operation, first cut off the damaged edges.

As in the implementation construction operations, and for household needs, the following connection methods can be used:

welding with a soldering iron equipped special attachments- at the same time he acts as homemade apparatus for welding;
joining when heated, melting the film with an iron;
the required temperature of the layers is achieved using a burner;
industrial equipment is used to heat the seam.

You can try to warm up the film with a hair dryer, then tightly connect the surfaces intended for gluing with each other, or it is better to put it under a press.

Film welding with a soldering iron

How to glue plastic wrap with a soldering iron? This method can be safely attributed to the most common - the tool is easily accessible, it allows you to get a good result, and with a little refinement of the soldering iron, the effect can be improved.

It should be borne in mind that without modification it will not always be possible to make a tight connection - the joints may be uneven, the material spreads.

So you can glue the greenhouse film or make a canvas for other needs. Only with very small amounts of work can we recommend using a PVC connection with a soldering iron. After a little refinement, it turns into a convenient and easy-to-use tool.

Iron as a welding heater

How to glue the film using an iron - the simplest household appliance that is in every home? Everything is very simple - the work consists in melting the polyethylene and creating joints using the heated soleplate of the iron.

Improvised welding machine from the iron allows you to connect large areas of film... In this case, the seams can be made with a certain width. All modern irons have a thermostat that allows you to adjust the heating temperature.

Before gluing the film, ensure comfortable spot for work - a smooth wooden surface is best.
The film is laid with an overlap, upper layer covered with fluoroplastic or paper, the sole of the iron is pressed and led along the welding line.
The clamping speed, force are determined empirically, the temperature is selected.

Professional tools for welding

To connect the film at home, you can make a variety of tools with your own hands, but they are suitable only for performing small-scale work. If large-scale production is required - commercial activities, the creation of a greenhouse or greenhouses - the use of these devices has the greatest effect. No adhesive has the same ability.

The welding process is faster, professional devices allow you to set the desired pressure parameters, the speed of advancement along the weld, and temperature.

Most professional devices there are tensioning and driving roller elements that pull the film from optimal speed, which has a beneficial effect on the quality of the seam.

Polyethylene is an unpretentious and inexpensive material, therefore it is actively used in everyday life and in some cases is irreplaceable. Sometimes situations arise in which it is necessary to glue the material, for example, when building a greenhouse. In this case, not all compositions are effective; you will need to use a special adhesive for polyethylene, which has excellent adhesion properties.

Technical characteristics of polyethylene

Polyethylene film is used as insulation, packaging material, electrical insulator. It can reliably protect against moisture and absorbs neutrons, which are a type of radioactive radiation. Foamed polyethylene, which is otherwise called isolon or polyfol, is used to insulate a home - they are pasted over the walls with it.

The question of how to glue polyethylene arises quite often. The usual composition is not suitable for these purposes, since the material is chemically inert. A special adhesive for polyethylene is required.

The bonding of polyethylene is an electrical and chemical process. The adhesive composition should adhere well to the surface of the film, and after hardening, reliably adhere the surfaces to each other.

There are two ways to firmly glue polyethylene:

High temperature welding (iron).
The use of adhesives.

Types of glue and their manufacturers

Overwhelming majority adhesives practically do not stick to polyethylene, simply squeezing out of the contact area. Still, there are materials that can cope with such a difficult task.

The most popular types of adhesives that can be used for polyethylene are:

BF-2, BF-4;
two-component acrylate;
epoxy.

Butyralphenol glue (abbreviated as BF) is produced in Russia, the manufacturer is CJSC "Petrokhim" in the city of St. Petersburg. The glue is a viscous, thick liquid of brown or reddish-brown color, does not rot and corrode.

Suitable for bonding metal, plastic, ceramics and wood, used in restoration work. The glue should not be used for dishes, as it contains toxic aldehydes and phenol. BF-2 is universal, chemically inert and moisture resistant.

In terms of chemical resistance, it practically does not differ from BF-2, but its scope of application is slightly different. BF-4 is usually used for bonding elastic materials that are subject to vibration and bending. For example, leather, wood, plexiglass, textolite, metals and alloys.

Two-component acrylate glue is characterized by increased strength, it is transparent and does not harden very quickly (in 4 minutes), which allows you to take your time when working. Excellent adhesion to metal and plexiglass.

Epoxy adhesive "Contact" transparent produced by LLC ROSEL, St. Petersburg based on polyepoxy resin and hardener. It is used to repair fiberglass, porcelain, wood, faience, glass, metal and various alloys. The composition perfectly fills cracks, voids and gaps, restores the shape and volume of objects. The seam is resistant to gasoline, oil and water.

Which is better

Among all the compounds that are able to glue a polyethylene film, the leading position is occupied by glue designed specifically for materials with poor adhesion. It is a filled acrylate adhesive. In its composition there are very small glass balls that do not allow the compound to slip out of the gluing site, they form a gap of optimal thickness.

For foamed polyethylene, ruler glue is perfect KLEYBERG 152-1 due to its unique composition and wide range of uses.

Application

Before using the composition, thoroughly degrease and dry the surfaces. You can apply glue exclusively from the mixer that is included in the package. Maximum mechanical strength the seam for polyethylene comes in 4 or 5 hours. Optimum for work is the air temperature from +21 to + 23˚ С.

Advice
In a liquid state, the glue is no longer than three minutes, so dock the surfaces immediately after applying the composition.

It is not intended for gluing polyethylene surfaces, but the phenol-formaldehyde resin included in its composition has excellent adhesion to such material.

Application of epoxy adhesive:

Rub the areas to be glued sandpaper, degrease and dry.
Treat surfaces with chromic anhydride (15-20% solution) or potassium dichromate (20-30%). You need to work with them with extreme caution, since these substances are very caustic and dangerous carcinogens.
Dry the surfaces after processing.
Prepare epoxy adhesive according to package directions.
Apply the thinnest layer of adhesive to both surfaces and bond immediately.
Leave for several hours, or better for a whole day at a temperature of +30 to + 45˚C, so that the seam is completely frozen.

Advice
Chromic anhydride and potassium dichromate can be replaced with a strong solution of potassium permanganate, which is also a strong oxidizing agent. It is no less effective, but safer, although it can also leave a chemical burn.

If very high requirements are imposed on the strength of the formed seam, then optimal way gluing polyethylene - welding. The seam will be strong if it is not allowed to cool quickly.
No mechanical preparation of the surface is required before using the filled acrylate adhesive. Except for degreasing and cleaning, which are carried out before gluing any surfaces.
Exposure of the seam formed after gluing the film acrylate glue should be carried out at temperatures from +15 to + 70˚ C for 4-5 hours.
Epoxy glue is difficult to work with and the bond strength is not very good.

Advice
You can derive your own recipe for polyethylene glue by adding a little crushed chalk or cement to the acrylate glue. The composition can turn out to be of high quality and at the same time inexpensive.

The best option for gluing polyethylene is welding, since the result is a durable, reliable seam... It is not always advisable to use adhesives, this is due to the fact that polyethylene is a chemically inert material with poor adhesive properties.

The need to glue panels of film for greenhouses occurs quite often: in case of breaks after long-term storage or improper installation, when covering a wide greenhouse, when standard sizes lacks. All gluing options are simple and available for domestic use.

Hot gluing methods

The most common bonding method requires an iron or soldering iron and (optional, but desirable) fluoroplastic tape. You can also use an iron roller heated to 250C. Place the panels to be glued on top of each other and slowly drive through the fluoroplastic tape with an iron or a soldering iron tip. The width of the overlap should be 1-2 cm. If there is no fluoroplastic tape, then plain paper or even a strip of newspaper will do, which must be folded in half. Before starting bonding, it is best to practice to find the optimal holding time. Carry out the gluing process together: the assistant should stretch the film, at the same time smoothing it. After the job is completed, do not rush to tear off the strips of paper, otherwise you may damage the film.

The second method is to use wide strips of metal (5-10 cm) and a blowtorch. Clamp the two pieces of adhesive between the metal strips and flat surface so that an overlap of 1-1.5 cm is obtained. Then heat this place with a blowtorch, being careful not to overheat the metal and melt the film under it.

Cold joining methods

The polyethylene film can be joined using various adhesives: "Moment", BF-2, BF-4. Before gluing, treat the surfaces of the panels (gluing points) with chromium anhydride (25% solution). If you intend to connect a polyamide film, then you will need PK5 glue. In this case, after gluing, the seam must be ironed with an iron heated to 50-60C. If there is no glue at all, and the film must be connected, then you can use "folk" means: concentrated acetic acid (80%) or xylene. In any case, first, the junction must be warmed up to a temperature of 70-75C. Care must be taken when working with these formulations.
Sometimes in garden stores you can find special superglue designed for gluing plastic wrap. This chemical is odorless, can be stored indefinitely, while the connection is smooth and strong. A 50 ml bottle is enough to join a seam 1 cm wide and 15-20 m long. It should be remembered that not all adhesives are suitable for joining a film; for example, any type of hot melt glue will not work. On the other hand, good results are shown by compounds used in advertising for bonding banner strips: for example, "Fix-Ol" (Sadolin), which is suitable for gluing even thick PVC films.

In construction, polyethylene film is used mostly as a waterproofing or heat insulator, if it comes about film greenhouses. It has polyethylene and certain sound insulation properties, but not sufficient to be used as an independent sound insulator.

For gluing polyethylene, it is necessary to purchase such glue in advance, which is used for gluing plastic.

Can polyethylene be glued?

When installing waterproofing or greenhouses, it often becomes necessary to glue several pieces of polyethylene to get a film the right size... But how to glue the plastic wrap, and is it possible to do it at home?

The question is not as simple as it seems initially. It is also known from the school chemistry course: the higher the polarity of the polymer material, the better it lends itself to gluing. The polyethylene molecule written in chemical symbols is very similar to a long chain, consisting of the same links - CH2-. This uniformity suggests that electric charges are evenly distributed inside the polyethylene molecule, i.e. it is non-polar. Therefore, polyethylene sticks together very poorly.

Welding of a polymer film: a - using an electric soldering iron; b - with the help of an electric iron runner; c - with an open flame.

Very often for gluing polymer materials use adhesive mixtures, which are prepared from the same materials (or similar), dissolved in a suitable solvent. But this will not work with polyethylene - it practically does not dissolve in organic solvents.

Some polymers can be glued just because they have a rough surface. In this case adhesive solution fills in irregularities and, freezing, clings to them, tightly gluing together pieces of material. But this cannot be done with polyethylene, since it has a perfectly smooth surface.

Therefore, if we talk specifically about the gluing process, then it is almost impossible to glue the plastic wrap at home. And in the industrial sector it has never been glued.

But although pieces of polyethylene cannot be glued together, they can be welded, or, more precisely, soldered, which has been successfully done for many years in industry, having developed many methods of such welding. But of this many methods, there are only two that can be applied at home.

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Welding polyethylene with a hot object

Welding the film using an electric soldering iron: a - type of seam; b - an electric soldering iron device for welding a film.

The most convenient way to do this is with a metal roller with a heating device inside. But to make such a device at home, you need to have a sufficiently high qualification of an electrician.

Therefore, folk ingenuity has found a completely satisfactory replacement for such an instrument - an ordinary iron. Since the plastic wrap different brands melts at different temperatures, then there are no specific recommendations for temperature regime welding cannot be given.

The heating temperature of the welding iron will have to be determined by trial and error. If the temperature of the iron turns out to be insufficient, the film will not boil, but if the iron is heated too much, the seam will turn out to be "overcooked", weak, and besides, the film on the sides of the seam will easily break. The only thing that can be advised initially is that the iron should not be too hot.

The soldering technology itself is very simple. To make the seam neat and even, it is better to weld on a flat wooden surface... The edges of the film should be placed on this surface with a slight overlap (0.5-1 cm). Along this overlap, you need to draw with the spout or edge of the heated iron. The passage should be no more than a second in one place, otherwise you will lose the film.

PVC film can be recognized by the yellowish tint of the roll edge.

But with this method of soldering, there is one very important negative point: The heated plastic wrap often sticks to the iron. To prevent this from happening, it is better to cover the polyethylene seam with a thin sheet of cellophane before soldering, and then go over it with an iron.

The strength of the seam can be checked by simply pulling the sealed pieces in different directions. If the seam diverges, it means that the quality of the soldering is unsatisfactory, and you need to repeat everything from the very beginning. Some craftsmen perform this soldering not with an iron, but with a red-hot knife blade, claiming that it is more convenient for them. But this is already a matter of taste.

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Open flame welding of polyethylene

To verify polyethylene in this way you will need:

metal or ceramic bars;
welding tool (it can be gas-burner, blowtorch, spirit lamp, and in the absence of these, you can use a torch or even ordinary matches).

Electric circuit diagram connecting the "iron" to the network: 1 - constant wire-wound resistor; 2 - metal case; 3 - sting-ridge; 4 - textolite handle; 5 - stand.

The edges of the films to be welded must be fixed with metal or ceramic bars (wooden ones are not suitable for this purpose). It is necessary to fix it in such a way that a narrow strip of film (3-5 mm, no more) is visible from under them at the welding site. The bars are needed not only for fixing the film, but mainly in order to quickly remove heat from the films being welded, otherwise they, instead of melting, will burn out entirely.

Then you need to draw along the remaining open edge with a flame. The speed of the flame will also have to be adjusted empirically, especially since it will be different not only for each grade of polyethylene, but for each instrument too. If the operation is performed correctly, then upon its completion, a dense roll forms, firmly connecting the two edges of the plastic film.

As an alternative to welding, when setting up greenhouses and greenhouses, two pieces of plastic sheeting can be stitched together. To do this, two pieces of film are overlapped on top of each other. The overlap should be 2-2.5 cm. Then an ordinary medical plaster is glued to the overlap on both sides. He will not hold on well, but this is not scary, the main thing is that the strips of the plaster lie exactly in the place of the overlap, one above the other.

Then, over the overlap, make two seams with large stitches. In this case, pieces of film are fastened with stitched threads, and the plaster, having a more durable structure of the material, prevents the threads from tearing the polyethylene. However, this method is not suitable for waterproofing, since the joints will allow moisture to pass through.

It should be noted that both welding methods are suitable only if it is necessary to combine polyethylene with polyethylene.

If it becomes necessary to glue the film to some other material, then you will have to look for a transparent film made of another material, which adheres better, and for which there are special adhesives on sale. Alternatively, it can be a polyvinyl chloride film.

Connect the plastic wrap in the described ways or look for something new, it's up to you. The main thing is not to be afraid to experiment, because if something cannot be done today, this does not mean at all that it cannot be done tomorrow or the day after tomorrow.

By parameters, photo, cost.

The LENTAPAK company produces and sells wholesale and retail various polyethylene films:
- greenhouse;
- technical;
- construction.

The length of the rolls is from 15 to 100 m, the width is from 1000 to 1500 mm.

Buyers are wondering how to get a large, solid piece or how to glue plastic wrap stronger. After all, thanks to the high quality characteristics- elasticity, lightness, strength - our products are used not only in everyday life, but also in many sectors of the economy:
- in construction for waterproofing foundations, basements and ceilings;
- in agrotechnical production for growing early vegetables, flowers and berries;
- in transport companies for the shelter of goods.