BF-2 glue (phenol polyvinyl acetate) was developed by G.S. Petrov back in the middle of the 20th century, but there are still no analogues to it in composition. The adhesive mixture has a viscous, not too thick consistency, a pungent odor and not a very bright color. The technical characteristics of the composition guarantee strong bonding of any surfaces.
It is considered the best when restoring antique items. Suitable for modeling. Used in medicine (dentistry), in the furniture industry. The adhesive should not be used for kitchen or other products in which food is prepared, stored or consumed. It is actively used in the repair of acoustic equipment and radio devices.
Specifications
| Characteristic | Description |
| Appearance | Transparent liquid. Slight turbidity with a yellow or partially red tint is acceptable. |
| Conditional viscosity | 30-60 s at temperature +20°C |
| Dry residue fraction | 14-17% |
| Shear strength of adhesive joint | 19.5-20 mPa or 200 kgf/sq.cm. at a temperature of +20°C |
| Bend of the dried glue seam | < 3 mm |
The use of BF-2 provides strong adhesive seams with low elasticity. The glue easily withstands high temperatures (up to 200 °C). Working properties of the adhesive composition:
- invulnerability to mold;
- resistance to chemicals, acetone, gasoline and alcohol;
- viscosity in the range of 30-60 Pa*s at a temperature of 20-25°C.
The viscosity of the glue can be increased by storing it at sub-zero temperatures.
Before use, the product must be kept at room temperature for at least 1-2 days. Heating the product with a hairdryer or storing it near heating appliances is dangerous.
Removing BF glue from surfaces
BF adhesives are easily removed from clothing or leather products using a sponge dipped in a clear alcohol-containing liquid (even vodka will do).
After the first treatment of the contaminated surface, you should wait 20 minutes, after which you should also remove residual traces of glue with a sponge.
To clean the fabric, use a cotton pad soaked in solvent. You should first test the fabric on an inconspicuous area or the reverse side for color fastness.
Areas of use
The use of BF-2 glue is recommended for joining parts that will not move during operation or be subject to dynamic loads. The result must remain motionless, otherwise the seam itself may become deformed. This is due to its inelasticity after hardening.
Glue can be used to connect:
- metal;
- tile;
- tree;
- marble and porcelain stoneware;
- glass;
- ceramics;
- polymer coatings.
The parts glued together can be of different materials, for example, a wooden base with glass or plastic with ceramics.
BF-2 has different release forms: tubes, cans and small bottles
What can replace BF 2?
There is no analogue to this composition. Some experts believe that “Super Cement” can be used, however, when working with metals it does not always give the desired result.
The familiar phrase “break - don’t build” will be quite comparable with “make - don’t repair.” When manufacturing, the contractor has in his hands the technology of work developed by specialists, and without fail tested. There is also a list of all the necessary tools and equipment. And the repairman, by and large, has only experience at his heart. This means a generalist repairman who takes on any or almost any repair, and not one who sits on just one operation. A great help in repairs, both a universal tool and a universal repair material. For example, good glue.
For a long time, I literally poked around in search of “my” glue. In the background of the photo is only a small fraction of what I tried. There are no words, epoxy glue is good, but this process of mixing the components immediately before gluing (especially with a meager amount of work) completely deprives it of its mobility of use.
The meanest representative of the adhesive fraternity are tubes with a catchy Moment logo - now filled with adhesive composition, not even half, but a third. Despite its external attractive round plumpness, it will be enough for one, maximum two times, and not even because it is not enough, but because everything unused will simply dry out, because two-thirds of it is air inside.
The glue from the “second” line used to be not bad and not expensive, but this was before, and besides, it is the most untidy - where it smeared there and remained, you can’t get it off without consequences. Master foam ceiling tile adhesive is only suitable for non-critical work.
There is also a hot-melt adhesive gun, but this is where very great care is not needed, where you need to, excuse me, stick something to something. I’m generally silent about the office guy - “his number is seventeen.”
And then, in a radio store, my eyes saw good old glue from the BF brand. Specifically, BF-2 and BF4 cost 95 rubles per plastic bottle with a capacity of 100 milliliters (80 grams).
BF glue is a phenol-formaldehyde resin with an additive that is dissolved in ethyl alcohol or acetone. The number after the letters “BF” indicates the content of the additive. With an increase in the number of additives, the elasticity of the seam increases, but, alas, the strength decreases.
I tested it on an element of electrical fittings (fastening the lampshade of a floor lamp) made of an unknown type of plastic produced long before perestroika. The “second” glue “didn’t take it”, but BF-2 for its dear soul (I glued the fastener according to all the instructions and dried it for 24 hours, clamped in a vice).
Next was attaching the radio pocket. Two types of dissimilar plastic were glued together. Successful.
At the same time, as if on purpose, the lid of the brewing mug once again slipped onto the table and split in half (before this it had fallen regularly and was intact). The glue also worked on ceramics. Only if you look closely you can see a slightly noticeable trace of the split.
But the glue helped the most in the case of a cracked chandelier lampshade (bored holes for European standard electric sockets). The material to be glued is glass. This is how many interesting things I could have heard about myself and my repair skills if I had not been able to glue together the lampshade that had fallen into three pieces. The entire chandelier would have to be thrown away. There are no lampshades for sale separately, neither these nor any others. And so only a small trace remains, the chandelier functions and pleases the eye, as if nothing had happened. And only you and I know about this secret))
Finally, the miniature spoon was repaired. Material: 925 sterling silver. It would be necessary to take it to a jeweler, the asking price is only 500 rubles, but the owner, a young, somewhat sentimental lady, did not want to give a very personal thing into the wrong hands. I selected a gold-colored tube as a connecting element, tinned it a little in places (now it’s in the general palette of once gold-plated silver “it doesn’t spoil the track”) and filled it with glue.
What gave my soul peace of mind: I made so much and there was almost no less glue in the bottle. Enough for a long time. The only disappointing thing is that the expiration date expired a month after purchase. But I think this is not significant, you can still use it for a year without problems. Glue is convenient because when gluing, you can take your time and do everything carefully (correct the parts being glued, remove excess without leaving a trace). And what takes a long time to dry, holds tightly. Author of the material: Babay iz Barnaula.
Discuss the article USING BF-2 GLUE FOR REPAIRS
BF glue and its varieties have been used in everyday life and in repair work for decades. This product is perfect for gluing different materials, from fabric and plastic to ferrous metals. The series even contains medical glue; it is used to “seal” wounds and abrasions.
Instructions for use
The composition requires double application of layers. BF-2 can be used to cover surfaces as an alternative to paint and varnish products and impregnation, for example, in the process of restoring something.
The instructions consist of a step-by-step process.
- Processing areas that need to be glued later. The work depends on the characteristics of the materials themselves, for example, metal needs to be cleaned with sandpaper and thoroughly wiped with a rag soaked in gasoline (or any other composition with a degreasing effect). Plastic and glass can be treated with a hot baking soda spray.
- It is better to apply the adhesive mixture with a clean thin brush on both sides. The glue layer should be thin and uniform. If it is applied cold, it takes 20 minutes to dry; when applied hot, it takes at least an hour.
- The second layer must be applied using the same method as the first (either cold or hot). There should be no gaps or leaks.
With the hot gluing method, the joined parts must be clamped in a vice and placed in the oven for 60 minutes. The internal temperature should be around 130-140 °C. When gluing cold, after applying the second layer, you need to wait 2-3 minutes, then press the parts tightly and leave everything in a warm, ventilated room for a day. The hot joining method can be used when working with marble, metal and earthenware. Cold – for the restoration of vases, dishes and various models. The part will be ready for use in no less than 24-48 hours.
If glue gets on the skin of your hands, it should be washed off with regular running water.
Storage and transportation
Phenol polyvinyl acetate glue brand BF-2 should be stored in hermetically sealed containers.
Do not allow it to be near a source of fire or possible fire. The storage place should be out of reach of children, dark and dry. The mixture itself can only remain in its original packaging.
Transportation is possible by rail, road, and air. The main condition is compliance with sub-zero air temperatures.
Analogs
There is not a single analogue of the BF-2 category. None of the manufacturers use phenol-formaldehyde resin as a component. You can choose a replacement that matches the technical characteristics of the BF-2 as closely as possible.
For example, “Super cement” has a reduced adhesion ability of the composition and the strength of the finished seam. Not intended for use on metal surfaces. You can try replacing the glue with any product made on the basis of epoxy resin. It is toxic and fire hazardous. This must be remembered before starting use.
The manufacturer has a variety of adhesive mixtures of the BF brand.
- BF-2n or BF-4n (only for ferrous metal).
- BF-4 can be used to maintain the elasticity of seams that will be susceptible to vibration.
- Medical glue BF-6 is the best option when working with textiles and leather, and is used in medicine.
- BF-19 is non-toxic, connects ceramics, wood and textiles (hot method), rubber, cardboard, leather and textiles (cold method).
- BF-88 is a fire hazardous product that firmly connects metal and non-metallic components.
All types of glue used in medicine (dentistry) are purchased in pharmacies or specialty stores that sell medical equipment.
Glue composition
Depending on the specific brand, the chemical composition of BF glue may be different. All products in the series are produced in accordance with GOST 12172-74.
By deciphering the name (butyraphenol glue), a specialist will understand that the main component is polyvinyl butyral (or polyvinyl acetal). The number after the BF brand indicates the percentage of the main component in the dry matter, which gives the material elasticity.
Different types of BF may have an unequal number of such components - the more there are, the higher the plasticity of the dry adhesive layer, but the lower the strength. The glue contains:
- phenol-formaldehyde or phenol-polyvinyl acetate resin;
- ethyl alcohol (solvent).
The last component can be replaced by the manufacturer with chloroform or acetone. Medical glue BF-6 is dissolved only with alcohol.
In appearance, all products are thick solutions of yellowish, brown, brown, reddish color. Adhesives are flammable.
