Currently, you will not surprise anyone with such a tool as cyanoacrylate second glue, better known to buyers as superglue. These tools are used to quickly and easily connect various types of materials (metals, wood, glass, plastic, etc.).
A bit of history
Cyanoacrylate glue was created during the Second World War by the American scientist Harry Coover. He worked for the Eastman Kodak camera company. In wartime, the scientist was developing a transparent plastic that could be used in optical sights. The resulting substance was unsuitable for the task. This was due to a change in properties when moisture got in: the substance became sticky.
And only after more than ten years, Coover realized that the substance he had created could benefit people. It was originally used to heal wounds during the Vietnam War.
A year later, cyanoacrylate glue was introduced to mankind. From that time heremains in demand among buyers.
Chemical side of the process
The main component of the glue is cyanoacrylate, that is, cyanoacrylic acid ester. Its amount can reach 90-99% of the total composition.
Plasticizers (up to 10%), thickeners, stabilizers, activators are added to the ether. An important feature is that the adhesive does not contain solvents.
The bonding process is based on the reaction of anionic polymerization of cyanoacrylate with a slightly alkaline agent (most often water). With a thin layer of glue (up to 1 mm), the humidity in the air and on the surfaces to be glued is sufficient for the reaction to proceed. Under the influence of moisture, the stabilizer in the adhesive splits. This starts the polymerization reaction between the surfaces.
Optimal conditions are room temperature and humidity of 40-60%. Under these conditions, the best results that cyanoacrylate adhesive can give are achieved. Application of the product at lower air humidity will result in an increase in drying time. Higher humidity will reduce bond quality and strength.
Basic Features
Cyanoacrylate glue (price within 500 rubles per 50 grams) is a colorless substance with a slight odor that disappears after drying. Has the following technical data:
Consists entirely of solids
Solvent free
Viscosity is approximately 1.5 thousand cps
Basic properties of the dried glue:
Resistant to high temperatures (long-term heating up to 80 degrees or short-term heating up to 100 degrees)
Withstands low temperatures (up to minus 20 degrees). At lower temperatures, the tensile strength decreases
Keep immersed in water for several weeks
Resistant to solvents (acetone, alcohol, petroleum products, gasoline, engine oil) and chemicals. Only alkalis can affect adhesion strength
Holds a load of 150-250kg/cm3.
Scope of application
Cyanoacrylate glue is most often used for quick connection of non-porous materials: for mounting elements of radio equipment, rubber seals in a window (door) opening, fastening microcircuits, circuit boards, harnesses, individual parts of assemblies in instrumentation.
One type of "superglue", octyl-2-cyanoacrylate, due to its fast setting and minimal toxicity, is used in surgery to stop bleeding and glue wounds. Recently it has become possible to use glue for fractures.
In everyday life, superglue is used to fill seams and cracks. To do this, it is combined with baking soda. The resulting mixture hardens very quickly and looks like plastic.
Cyanoacrylate glue can be considered a universal remedy. It is used in all fields: medicine, toy industry, aircraft industry, automotive industry, toy and decoration industry,footwear, sanitary ware, advertising industry and many others.
Use
The surfaces to be bonded must be free of dust, rust and oil stains. The tool should be at room temperature for about a day. After that, you can use cyanoacrylate glue. The activator may be needed in cases with adverse conditions, to cover large gaps. It can be used both before gluing (application on one surface) and after (spraying on the adhesive).
On one of the surfaces glue is applied in minimal quantities. To make the layer even, you can use a plastic spatula. On large areas, the adhesive is applied in drops. Next, the surfaces are connected and tightly compressed.
Glue hardens at room temperature. At 20 degrees Celsius, it only takes a few minutes. This process can be accelerated if there is moisture on the surfaces to be bonded.
Glue “seizes” in just a couple of seconds. The glue completely hardens in a day at 20 degrees and air humidity more than 55%.
Safety
All work involving the use of cyanoacrylate adhesive must be done outdoors. Work indoors is only allowed with forced ventilation.
Do not allow glue to get on the skin, eyes, digestive system.
Dry glue in a tube must not be squeezed out by force, otherwise an uncontrolled jet of the product may get into the eyes. In such a case, the spout is carefully pierced with a pin (preferably hot).
"Glued" fingers should not be torn by force or cut with a knife. This will only damage the skin. For such cases, use acetone (or a similar agent) applied to the napkin. Acetone will soften the glue, but not instantly. This will take some time (up to an hour in difficult situations).
It is strictly forbidden to wear cotton clothing (in particular gloves) when working with glue. When the adhesive comes into contact with the cellulose of the fabric, a reaction occurs with the release of a large amount of heat. This may cause burns.
