Features of conductive glue: composition and advantages, how to make an electrically conductive composition with your own hands

The scope of application of electricity is very wide. Modern man can no longer imagine his existence without various kinds of electrical appliances. Starting from electronic mobile gadgets and to the banal lighting in the house - all this is a part of our life, helping to work and have fun.

Means for the repair of equipment

All devices powered by electric current have one big drawback: the ability fail. And here you have to turn to specialists of different levels: from professional electronics engineers to home-grown radio amateurs.

Their field of activity involves the repair and adjustment of an extremely wide range of equipment. And if in one case you can get by with quite standard and familiar means, then in others you have to find more rational and cunning approaches for high-quality restoration of the malfunctioning equipment.

One of these means is conductive glue, or conductive varnish. After all, thanks to them, the repair of complex electronic equipment it becomes much easier, and sometimes even the only possible one.

What is Conductive Adhesive

This is a special semi-liquid composition with conductive properties and a fairly wide range of applications, ranging from recovery printed circuit boards and ending with a number of car repair works. And due to its heat-resistant qualities, it is able to further expand the field of application. The composition of this glue contains a dispersed powder of metals with good electrical conductivity data, such as gold, silver, nickel, palladium.

Along with the convenience and accessibility, the conductive glue has many interesting features:

• The ability to adhere perfectly to any surface, i.e. has a so-called high adhesion;
• The ability to be used at a heating temperature of up to 180 degrees;
• After exposure to temperatures, it does not lose its physical and chemical properties;
• It perfectly tolerates temperature extremes;
• Besides excellent electrical conductivity, it is a good sealant;
• When using the applicator, it can be applied in a very thin layer;
• Dries quickly, which increases the speed of the work performed.

Applications

The scope of application of this glue is truly wide. For example, where work with a soldering iron is impossible, due to the too small dimensions of the parts or their susceptibility to high temperatures, he simply irreplaceable.

The most demanded areas of application for electrically conductive adhesives and varnishes:

• Bonding and restoration of heating filaments on car windows;
• In radio devices - connection of piezoceramic parts;
• To connect dielectrics, through which electrical communications must pass;
• For connecting conductors of too small cross-section, where hot soldering is simply impossible;
• For "cold" soldering;
• Restoration of broken tracks in various devices: keyboards, remotes, printed circuit boards, etc.;
• It is used in the repair of high-tech devices: phones, e-books, computers, etc., for attaching microcircuits and crystals to boards;
• Acts as a base for enamel or paint with conductive properties;
• Restores conductivity in damaged areas of various devices;
• It is used in the installation and repair of electrical heating systems, "warm" floors.

Of course, the possibilities of adhesives and varnishes, capable of conducting current, much wider, but the above list is quite capable of impressing with the scope of the possibilities of such a composition.

Features and requirements

Having so wide range of applications, an electrically conductive glue must have certain characteristics in order to perform the tasks assigned to it efficiently.

First of all, it must provide sufficient electrical conductivity. That is why it is customary to use ordinary graphite, nickel, gold, polymers, silver and other powdered metal that conducts current well as one of the components.

The second component is adhesive base. It should have a minimum resistivity and have good elasticity so as not to spread during application. It is very important here to maintain a certain ratio between the polymer binder and the conductive powder material. So, an excess of the content in the composition of the current-carrying elements can lead to a decrease in adhesion, which reduces the reliability of the contact.

Another requirement for the quality of the glue is the drying speed. The faster this happens, the more convenient and faster the master can work.

And, of course, the conductive composition must be heat resistant and safe, since many semiconductors and microcircuits heat up during operation.

DIY glue preparation

Due to the fact that industrial compositions have a high price, besides, sometimes a lot of glue is needed, for example, for repairing the glass of a car, it rises completely logical question about the possibility of making conductive glue with your own hands. It turns out you can. And at the same time, of a different composition. A few of the recipes most used by radio amateurs:

• Perhaps the most common way to create glue yourself. Here, the main bias is made on the main feature of such compositions - electrical conductivity. To do this, they buy the simplest and most affordable "Superglue", which is sold almost everywhere. Now you need to grind the lead from an ordinary simple pencil into a fine powder. This is not as easy as it might seem, but it is quite possible. It's good if you have an old and unnecessary blender in stock. It will help a lot in this problem. Now the resulting graphite dust must be mixed with superglue in a 1: 1 ratio. All is ready!
• This recipe will come in handy if you need to get the perfect glue for its electrically conductive qualities and at the same time with good adhesion. Here, as in the previous case, you need 15 grams of fine graphite powder. You also need vinyl chloride-vinyl acetate, a terpolymer in powder form, in an amount of 30 grams. Powdered silver - 35 g. And pure acetone with a volume of 35 ml. All components are thoroughly mixed in glass or porcelain dishes. In this case, the solution should look like a black-gray syrup. The viscosity of the adhesive can be adjusted with the amount of acetone. The resulting consistency must be poured into a glass jar with a well-ground cork. Stir with a glass or metal rod before use. The resulting adhesive has excellent electrical conductivity and bond strength. Well suited for repairing heating strips on glass, as well as where contact strength is required.
• Another interesting recipe, but with the inclusion of silver. So, you need to mix 6 grams of graphite and 65 grams of powdered silver. Now add a binder: nitrocellulose and rosin, 4 and 3 grams, respectively. We also add ethyl acetate and acetone, 25 g. This mixture must be moved carefully until smooth. After a while, the resulting glue will begin to thicken, therefore, at the time of use, acetone is added, which will give the desired viscosity. It is believed that this glue is just an ideal solution for repair work with a car, but it is not suitable for outdoor use.
• And in this recipe we need a cenoplak (a transparent solution of nitrocellulose in an organic solvent) and a regular graphite rod from a battery. Further, by analogy, we grind the graphite and mix it with the cenoplac to a gel-like state. Such glue can be used as a conductive adhesive for flat cables in car repairs, and for troubleshooting problems with small household appliances.

As you can see, do-it-yourself conductive glue is not so difficult to make yourself. The main thing here is the availability of all the necessary ingredients. And also it will not be superfluous to know that all the above types of glue must be stored in glassware with a tightly lapped lid.

Choice of factory electrically conductive adhesive

It is quite clear that making glue on your own is much more profitable, especially if you need a large amount. On the other hand, a solution created independently may not always have all the required properties. You can make a mistake in the ratios of the components, or simply the resulting consistency will not have all necessary qualities.

In this case, you should still pay attention to the factory counterparts. For example, try the most popular Kontakol glue.

By its consistency, this glue is similar to a paste, which contains a mixture of polyester, epoxy and some other resins. And electrical conductivity is provided by powders of gold, silver or palladium. Conductive adhesive Kontol will handle it perfectly with its task and at a price it is quite acceptable. However, recently on the shelves began to appear conductive adhesive Kontakol of inadequate quality. Therefore, it is preferable to contact the seller who gives guarantees.

Problems in use

When using adhesives, it is worth knowing some of the nuances so as not to spoil the part to which you are applying it.

One of the main problems can be called the complexity, and sometimes the inability to make long tracks. And also such compositions are not suitable for processing side tires. This is due to the fact that the glue dries very quickly. But it works great for gluing small areas. However, this problem is easy enough to solve simply by buying markers, and not tubes and brushes.

It is also necessary to take into account the fact of incompatibility of some materials. For example, if the glue is based on silver, then it will not work well with nickel and aluminum.

Another nuance, which should also not be forgotten, is the drying speed. Drying time is on average about 2 minutes. It's nice and convenient. But this may not always be enough. Therefore, it is worth paying attention when choosing how long it will dry.

Despite all the obvious advantages of electrically conductive compositions, there are, albeit few, but obvious disadvantages:

• Since the composition includes expensive components (silver, gold, palladium), the retail price may seem high to someone;
• The composition of such adhesives includes components that have a detrimental effect on human health. However, if the minimum safety rules are observed, such moments can be excluded;
• You can find out about the quality of the glue and how much it actually meets the stated requirements only by directly using it. But buying from a trusted seller will minimize the risks;
• May not work with all surfaces.

Choose a conductive adhesive based on your needs and keep the above tips in mind!