Advice 1: How to glue polyethylene

Polyethylene is widely used in the household, and for many it has become a necessity. The material is cheap and unpretentious. However, the owners are sometimes faced with a difficult problem – how to glue polyethylene? For example, you need to repair the product or to attach the joints of the film. Conventional adhesives is not cope, because the surface of this type of plastic has a poor ability to adhesion (adhesion). But to solve this problem you can still.
How to glue polyethylene
You will need
  • - double sided tape;
  • - soldering gun or iron;
  • - two metal plates;
  • - cotton fabric;
  • - chromic anhydride or bichromate;
  • glue BF-2 (phenolic butyral);
  • glue for polyethylene;
  • - personal protective equipment.
Connect the joints of plastic film using double-sided tape. This is the easiest and fastest way to attach to each other the parts made of this material. However, do not expect that glued parts will withstand a greater load.
Weld polyethylene is probably the most common method of joining parts of the film. It requires caution since during heat treatment, you risk to ruin the material. We can recommend three proven ways - put both sides of polyethylene bonded between two metal plates so that the edges of both parts slightly. Draw on them with soldering iron – the metal will not allow the plastic to curl up. If necessary, you can make a plastic patch, thermally treating the edges of the welded parts;- use the iron, heated to a maximum hot temperature. In this case, the details should be laid overlapping (not less than 1-1,5 cm). Lay under the backing layer film and the top flat strip cotton fabric and iron them;- to connect plastic parts can, dripping their melted plastic junction. So it is possible to repair not only the film, but other plastic items.
Find a suitable glue for plastics. The vast majority of adhesives will not work. Some mixtures can be used, but only after the surface preparation of plastic - it should become more active. To do this you have to equip the "mini-lab". So, after applying a solution of chromic anhydride (25%) of polyethylene, you can use the glue BF-2. The preparation of chromium you would get in stores chemicals or with friends chemists. Replace it with a bichromate.
Try the special glue for polyethylene, such as DP 8005 structural adhesive for plastics) or WEICON Easy-Mix PE-PP based structural adhesive for polyethylene and polypropylene). The main feature of such compositions that do not need pre-processing of the material. The compound changes the structure of the plastic surface, after which it is glued.
Working with chemicals in the repair of polyethylene is necessary extremely carefully - in the open air and with means of individual protection (gloves, overalls, mask and goggles). Drugs chromium is toxic, they leave indelible stains on clothing. If you have no conditions for work with chemicals, better not to risk it and do a more gentle manner.

Advice 2: How best to glue plastic

To firmly glue the plastic product, you need to establish what material it is made. Each of them has its own recovery method. But you can also use glue, which well connects most plastics.
Cyanoacrylate adhesive capable of firmly to glue most plastics
Before you can begin restoring items, you should try to determine what type of plastic it is made. The fact that some types, such as PTFE (Teflon), various modern polyurethane glue is almost impossible.

How to glue a thermosetting plastic

From this material the most products that surround people in everyday life. This is sockets and switches, the details of the alarm clocks and radios, decorative elements and other products. The thermoplastics include acrylic (plexiglass), polyvinyl chloride, polystyrene. A feature of these plastics is that in a heated condition, they have a fluidity. To ensure that the product is made from thermoplastic, it is necessary to slightly touch it with a hot soldering iron.

Glue a plastic can with bakelite varnish. Surfaces previously degreased with gasoline, then on the ends of the thin layer of binder. After that, the bonding of the part to firmly fix the clamps. Further, the product is placed in the oven, preheated to a temperature of 80oC. Here it should be within 2-3 hours. After some time, the temperature should begin to increase, gradually bringing it up to 100C.

Thermoplastics respond well to restoration with glue BF-2 or BF-4. In this case, it is also recommended to put bonded items in oven. But there is a peculiarity in applying the glue: first, it is applied in a thin layer, then allow time to dry (at least an hour), then the procedure is repeated. When the second binder layer dries, the details of the squeeze clamps and placed in an oven. If you have used BF-2, it should withstand 1 hour at a temperature of 80-100C. If BF-4 – the product is dried for 2-3 hours at a temperature of 60oC.

Another way to glue thermoplastics is to use a viscous substance made from dissolved in a solvent of the same piece of plastic. This method is good for thin-walled products, which are undesirable subject to strong heating. Plexiglas lends itself perfectly to gluing using a solution prepared from misconstruing Plexiglas dissolved in dichloromethane, vinegar or formic acid. After machining the ends of parts should be tightly interconnected and secure in the grip. After 6-7 hours, the product will be firmly glued.

What method of bonding plastic optimal?

A modern plastic product is excellent for bonding composition for treatment of joints of linoleum. It is sold in tubes of 100 ml and is called "SINTEX". This is the most simple and quick way to repair damaged plastic. The same property is possessed by most modern super-glues (e.g., cyanoacrylate).

If the product is made of solid but brittle plastics used in the manufacture of toys in the middle of the last century, it is recommended to use epoxy or cold weld. This plastic should not be heated. Getting started you need to remember that any material before the bonding needs to be cleaned of dust and degreased.
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