Choosing a good frost-resistant fixative: wood glue - which one is better. Wood glue - tips on selection and use Wood glue for wood speed

IN everyday life situations often arise related to the conduct of various works with wooden surfaces and wood products different breeds. To repair or make something yourself, it is not always appropriate to use nails or screws, so the question of choice arises effective remedy, which can be used for fastening. Most often, the choice is in favor of glue, but not all adhesives are recommended for working with wood.

Peculiarities

Wood glue is used everywhere, but the specifics of gluing such material are somewhat different from joining surfaces made of rubber or plastic. The technology for performing this work does not involve drying or pressing the elements against each other. The tree needs a different approach, which depends on the individual characteristics of each individual species. Today assortment adhesive compositions presented on the market with a wide variety of products.

But in this diversity, it’s easy to get confused and not figure out which products will be optimal for a given situation.

To do right choice composition that will provide the most durable connection, the following factors must be taken into account:

characteristics of the material - degree of adhesion, resin content;
the characteristics of each material that will be attached - wood with plastic or wood with wood;
level of load on the adhesive seam;
conditions for further use of the product.

You should also take into account the features of the adhesive composition, among which are:

gluing density level;
moisture resistance of products;
time required for completely dry;
multifunctionality of glue;
adhesive strength;
product toxicity indicators.

Species

Products for gluing wood have different compositions and areas of application. Most materials are positioned as universal products for which fasteners wooden elements– this is just one of the areas of use. Other products are produced as single-purpose formulations, so they are not intended for contact with other types of materials.

There are several different compositions.

PVA glue sometimes called dispersive adhesive.

The main characteristics of such products are:

lack of toxicity, due to which the composition can be used indoors without additional safety measures;
quick adhesion to the surface;
unlimited operational life of the product;
Can be used on any surface.

The disadvantage of this glue is the method of diluting it, which is based on adding water, which negatively affects the reliability of fixation in rooms with high level humidity. To ensure high-quality gluing of elements, it is recommended to add wood dust to this glue.

Epoxy glue is a two-component composition, the use of which requires mixing substances in a given ratio. The product provides strong fixation and is universal in terms of application. Epoxy compounds They are waterproof, resistant to aggressive substances and fuels and lubricants. The time for complete hardening depends on the thickness of the applied layer. The disadvantages of the material include the need to protect the skin and overconsumption, since it is impossible to calculate exactly how much ready-made solution will be needed to treat the surface.

BF- a type of glue that includes several options for the product. For wood materials, series 2 and 4 are recommended. This composition has the feature of very fast hardening. On average, this requires 50-60 minutes, but provided that the humidity and temperature are within normal limits.

The compositions must be applied in two layers with short intervals. The fourth series of glue is frost-resistant products. The disadvantage of BF is the need for mandatory preliminary cleaning of the wooden surface with degreasing.

Heat-resistant adhesives, produced in the form of rods. To work with such products you will need a special gun. The scope of application of the products mainly concerns fastening small parts or sealing defects in a wooden surface.
Wood adhesives. To work, the products need to be prepared. Wood glue is based on organic protein, which is the main adhesive substance. It is necessary to connect different wood materials: hardboard, paper, cardboard, wooden products. The natural composition ensures safety of use.

The origin of the main component of carpentry compositions is different.

Products are classified based on the type of raw materials.

Mezdrovy. The main component in such products is a substance that is formed during the processing of animal skin. The material can be produced in the form of flakes, tiles or powder.
Bone. The raw materials for it are the bone remains of animals. The products have an average price. It is better to use a transparent composition instead of unrefined mixtures with impurities.

Casein. Widely used in aircraft modeling and shipbuilding. It is neutral to dampness and forms a strong connection. To prepare the composition, you must strictly observe the proportions and time interval.
Fishy. It is prepared from the remains of fins and scales. The composition is considered a professional product intended for gluing surfaces with varying degrees of hardness. The glue has a fairly high cost, so it is positioned as a furniture glue and is used for the repair or restoration of expensive furniture.
Moisture-resistant solution. You can prepare it yourself using slaked lime and cottage cheese, which has recently curdled.

There is a certain technology for making wood glue. To do this, the dry mass is poured with water and left for 6-12 hours so that the composition completely absorbs moisture. Then the remaining water is drained, and the mixture is heated in a water bath until the substance is completely dissolved. The cooking process requires periodic stirring. It is important to control the process so that the mixture does not boil. The glue is applied strictly in the direction of the wood fibers, then the elements are pressed against each other and fixed. The main disadvantage of the product is the reduction in gluing efficiency in the case of wood moisture content exceeding 10%.

Syndeticone glue. It is prepared from wood glue with the addition of lime and powdered sugar. The product is distinguished by a high level of strength of the connection of elements. The adhesive is waterproof and resistant to chemicals. The disadvantage of the product is the rather long preparation process, since the mixture for the solution must be kept in water for 24 hours.
Glue paste. It is prepared on the basis of carpentry composition, wood ash and chalk. The material performs well when priming and puttying wood.
Polyurethane products. It is the most expensive among the above range. The material has a number positive features. The area where the composition is applied perfectly withstands high dynamic loads.

This material is ideal for repairing furniture, such as chair legs that become loose over time. The composition is also highly resistant to different temperatures, moisture and solar radiation. It is better to glue wooden structures that are used in extreme conditions with this particular composition.

Scope of application

One- and two-component PVA adhesives are used for gluing indoor surfaces. And two-component products with a hardener can easily be purchased for working with boards located outside the premises - stairs, garden furniture, window or door structures. Polyurethane liquid adhesives perfectly glue wood to wood, as well as ceramic tiles, plywood, metal and plastic. Products are considered ideal option for oily wood species. The alloy adhesive creates connections without fixing with a clamp and ensures the connection of parts with small gaps.

The contact composition forms an elastic seam that is resistant to mechanical stress. Glue provides reliable fixation textiles in production upholstered furniture and gluing large plastic pieces onto wood.

Superglue is most often used at home because it is a quick-drying compound. However, in addition to this, it is widely used for wood. It is indispensable for fastening small wooden elements and intermediate fixation of parts. The composition is recommended for sealing cracks on wooden surfaces, and can also be used to repair cutting kitchen board with your own hands.

Bone glue is an ideal product for working with antique furniture.

How to use?

Each type of wood glue requires compliance with individual rules, which affect the scope of application.

TO general methods worth mentioning:

the need to clean working surfaces before applying the composition;
carrying out test assembly without using glue.

Because parts that cannot be pressed together when applying slight pressure cannot be glued. The already connected parts using the composition must be fixed with clamps until the material dries completely. On average, the product hardens within a day. Glue, as a tool for fixing wooden elements together, is an old and very effective option, which has greatly enhanced its properties thanks to the latest technological developments. Any product contains detailed instructions about application on packaging.

Manufacturers

Wood glue on the market is represented by a wide variety of well-known brands. The leaders in this segment are Moment, Titebonde and Titan.

Titebond produced by the company Franklin International. The product is recommended for plywood furniture, floor wooden surfaces, as well as other types of work with wood. The composition does not include solvents, and the main components are natural and synthetic polymers. This feature ensures good adhesion of surfaces to each other.

There is a series of compositions Titebond II Premium, which is in great demand for work on the production of doors and windows. The composition has a high level of moisture resistance, so it performs well when used outdoors. Quite often, decoration is performed using this method. wooden facade various elements.

Company Henkel popular for its products "Super PVA D3 Moment". It is used for industrial purposes, as well as in everyday life for gluing cardboard, paper or plywood. Waterproof PVA glue acts as an additive in concrete solutions, due to which the plasticity of the finished mass increases. D4 compositions indicate a high class regarding the water resistance of the product. Such products are positioned as goods special purpose, therefore they have a high price.

"Moment Joiner"– the best Russian glue, which is an aqueous dispersion that perfectly glues any type of wood, as well as building materials. Professional carpenters celebrate it quick drying, availability and durability.

Glue is a mixture or substance, various multicomponent solutions, which are made on the basis of organic and inorganic substances. Connected using glue different materials: fabrics, wood, glass, metals, paper, leather, ceramics, rubber, plastics. Bonding occurs due to the formation of an adhesive bond between the surfaces being connected and the adhesive layer. The strength of adhesive joints can also be affected by cohesion to the adhesive surface. According to the type of gluing, all existing adhesives are divided into non-drying, drying adhesives and bonds based on polymerizing compositions.

Wood glue is used to firmly fasten parts made of wood and other wood-based materials, such as cardboard, plywood or hardboard.

The main component of this type of glue is a protein substance that ensures strong adhesion. Depending on the raw materials used in the manufacturing process, wood glue can be fish glue, bone glue, hide glue, etc.

Hide glue

It is made from leather trimmings, waste from tanneries and flesh - the subcutaneous layer of fiber that is cut off when tanning animal skins.

Bone glue

This glue is boiled down from bone waste and ground bones. This is the most common type of wood glue.

Isinglass

It is made from fish processing waste: fish heads, entrails, scales, etc. are used. It is usually used when performing restoration and other complex work that require high quality and craftsmanship.

Casein glue

Brown-yellow powder made from dry low-fat cottage cheese and alkali. During the manufacturing process, this powder is poured into cold water and stirred constantly.

PVA glue

PVA wood glue is produced in tubes that can be used immediately. It dries quickly, is not washed off with water, but has a short shelf life. Despite this, it is currently in great demand among people.

Mucilage

This type of glue has not been widely used because it has weak adhesive properties. It is mainly made from starch and is used in the process of gluing wood surfaces and cloth.

Carpenter's glue "Moment"

Moment Joiner adhesive is intended mainly for carpentry work, which primarily includes gluing furniture parts. 20 minutes after its application, the parts are fixed, and after 24 hours the structure gains strength.

Glue "Moment Joiner" has excellent adhesive ability and is chemically neutral. The glued materials do not change their color and shape. The composition does not cause allergies and leaves no odor after complete drying. Apply glue to a cleaned and degreased surface at temperatures above +10°C.

Properties

Wood glue is highly durable: under enormous loads, the destruction of the adjacent layer of wood in the structure mainly occurs, rather than the adhesive layer of the joint.

The glue is usually produced in yellow-brown granules or hard slabs. It is believed that the more transparent and lighter the slabs or granules, the better quality glue.

Preparing glue before work

Before starting work, dry wood glue needs to be prepared. To do this, granules (when using a glue tile, you need to wrap it in cloth and break it into small pieces with a hammer) are poured in advance cold water so that the water covers the dry glue. The mixture is kept until it becomes a soft gelatinous mass. Basically, depending on the amount of glue, the procedure takes 4-12 hours.

After swelling, the glue is cooked for 15 minutes with constant stirring in a water bath at 60-80 degrees, until a uniform liquid mass without lumps is formed. You cannot heat the glue over normal heat - if the solution burns or boils, its adhesive ability is significantly reduced.

For cooking, you should use special devices called “Kleyanka”, which have two metal vessels. Pour into a large vessel hot water, after which a smaller vessel with glue is inserted, and the glue is placed on low heat. Water is poured into the outer vessel so that when boiling it does not leak into the inner vessel with wood glue. It is better to choose glue boxes made of copper.

If necessary, it is easy to make such a device yourself from scrap materials. For example, you can take a large tin can as a vessel, and place a small one inside glass jar, which should be installed on a stand or hung on a wire.

To obtain the required consistency of the glue solution, hot boiled water is either added during cooking or the cooking time is increased to evaporate excess moisture. For gluing tenon and end joints, it is better to make the glue a little thicker than for planar joints of sheet materials (hardboard, plywood, etc.).

You should cook the amount of wood glue that is required to complete the current job, because, despite the available additives, over time the solution begins to lose its properties, and after three days it can rot and become moldy.

Application

Wood glue is used hot at temperatures up to 70 degrees until it thickens. As a rule, the glue is capable of maintaining the desired temperature of the composition in room conditions without the need to reheat it for 2 hours.

Carpenter's glue is evenly applied to the gluing areas using a small brush.

To prevent the hot solution from being squeezed out too much, it is necessary to give the applied layer time to dry - approximately 2-5 minutes. After this, the surfaces are connected, the parts are slightly rubbed against each other, compressed with a clamp (or tightly tied with twine) and left for 4-6 hours until they are glued.

For strong and high-quality gluing with wood glue, the parts to be glued must be dry. Wood should not have a moisture content of more than 10 percent, veneer - no more than 5 percent.

Improving the quality of glue

By adding various additives to finished wood glue, you can make it more universal, suitable for joining materials other than wood.

For example:

The moisture resistance of the adhesive joint increases significantly if you add 10 g to 40 g of dry wood glue linseed oil or natural drying oil.
To glue the skin, you need to add glycerin to the wood glue in a ratio of 1 tsp. half a liter of glue.
If you add sifted wood glue to hot wood glue wood ash or dry chalk powder, you can get an excellent putty paste.

When evaluating the variety of adhesive materials available, it is often difficult to know which adhesive is best to choose for a particular wood project. Optimal type The composition to create the most durable connection is selected based on many factors. The characteristics of wood are taken into account (its oiliness, degree of adhesion, etc.), the characteristics of the materials being joined (wood to wood, plastic, etc.), the nature of the loads on the adhesive joint, operating conditions (humidity, temperature changes) and a number of others moments. Having several basic types of glue in your workshop and knowing their properties well, you can easily choose the best option for solving any carpentry problem.

One- and two-component PVA adhesives

Scope of application. One-component adhesives based on polyvinyl acetate (PVA) resins are universal option for various wood projects used indoors. Due to their high moisture resistance, two-component compositions (with the additional inclusion of a hardener) are considered the best option for gluing wooden products used outdoors ( garden furniture, elements of external doors, window structures).

Performance properties. If used rarely, the composition may separate and form sediment. Therefore, it is recommended to shake or stir thoroughly before use. The glue is extremely easy to use.

Traces of dried glue appear under the stain and varnish layer.

Open time: 3-5 min.

Liquid polyurethane glue

Scope of application. Creates a strong connection not only when gluing wood to wood, but also when working with materials such as metal, ceramics, plastic, etc. It is indispensable when creating projects from oily wood.

Performance properties. Polyurethane adhesive consists almost entirely of solid synthetic resins. It has high strength, heat and water resistance. It hardens faster in a humid environment, so it is recommended to lightly wet the surfaces to be joined beforehand. After opening the bottle, carefully monitor the expiration date. You can read more about polyurethane glue in the article.

Compatible with finishing compounds . For gluing wood, special tinted PU adhesives are used, which form a light brown seam that is invisible on the texture of the product.

Open time: 20 minutes.

Polyurethane hot melt adhesive

Scope of application. Creating connections without fixing with a clamp; gluing loosely fitting elements with minor gaps; working with oily wood.

Performance properties. Polyurethane hot melt adhesive has very high adhesion to difficult-to-glue materials. The elements are fastened in 30-60 seconds, without the need to create large clamping forces and use clamps. But drying takes much longer: the gluing cannot be subjected to stress for the next 24 hours.

Compatibility with finishing compounds. When used as finishing nitro varnish, swelling may form in places where the materials come into contact.

Open time: 30-60 sec.

Epoxy glue

Scope of application. Gluing wood to wood, as well as dissimilar materials; creating strong and waterproof connections; filling gaps without loss of strength characteristics.

Performance properties. The adhesive consists of two components: resin and hardener. When mixed, they form a durable, water-resistant composition that does not shrink. By varying the ratio of the two components, you can adjust the working properties of the glue. When working with the material, large pressing forces are not required.

Compatibility with finishing compounds. It shows up under the stain, but is perfectly hidden under a layer of film coatings.

Open time: from one minute to an hour depending on percentage components.

Contact glue

Scope of application. Creation of elastic and waterproof seams that resist shock and vibration; gluing fabrics during production wooden furniture; sticking large plastic elements onto wooden surfaces.

Performance properties. The material is made on the basis of synthetic rubber and never hardens completely. The elements are glued together instantly, making it quite difficult to adjust the position of the parts. The connection is not phenomenally strong, but it is highly water resistant and able to absorb shock loads.

Compatibility with finishing compounds. Incompatible with solvent-based finishes because they destroy the adhesive layer.

Open time: from half an hour to 3 hours.

Cyanoacrylate glue (superglue)

Scope of application. Despite the fact that this glue is used mainly for household purposes, it finds no less wide application when working with wood. Superglue is indispensable if you need to fasten small parts, for example, segments. It is used to temporarily fix elements at intermediate stages of work on a project. Cyanoacrylate adhesive has been successfully used to seal small cracks in wood surfaces.

Performance properties. It hardens in a matter of seconds; correction of the position of the parts being glued is almost impossible.

Compatibility with finishing compounds. Connections using cyanoacrylate glue require filigree cleaning, since traces of it are not painted and appear under almost all types of finishes.

Open time: no more than 7 sec.

Bone glue

Scope of application. Best option for restoration old furniture, including antique ones.

Performance properties. The adhesive material is designed to dry under high pressure. Bone glue provides a reversible wood-to-wood bond: the joint can be disassembled using water or alcohol.

Compatibility with finishing compounds. The glue is tinted with aniline dye to match the final finish.

Open time: 30 minutes.

What is the water resistance class of the adhesive: D1, D2, D3 and D4?

To determine the water resistance of adhesive joints in Europe they use standard DIN EN 204. This classification has successfully taken root in our country.

Operating conditions for adhesive joints:

D1– in rooms at a temperature not exceeding 50°C (a short increase is allowed). D1 glue is designed for wood with a moisture content of up to 15%.

Wood in our life.
Nature has endowed wood with such a unique set of qualities that no other material on earth has: environmental friendliness, wear resistance, richness of textures, etc. It is impossible to list all the areas of its application. Here's just a short list:
construction;
furniture;
paper production;
musical instruments;
toys;
household utensils.
Despite the fact that this material is quite durable, it also tends to break, crack and split into pieces. In order to bring a damaged item back to life, wood gluing is necessary.

Factors influencing the choice of wood glue.
Mankind has invented a considerable number of adhesive compounds for woodworking. To know how to glue wood with best result, you need to have information about the range and characteristics of adhesives.
When deciding which glue to use, you need to take into account a wide variety of factors that may influence your choice. For example:
type of operation (glue a broken stool or connect thin carved fragments);
a set of connectable textures (glue wood to wood or fix it to metal, fabric, leather, etc.);
conditions under which the objects being glued will be used;
expected connection reliability;
time required for gluing;
price.
Expert advice: no matter what composition you use, to achieve strong adhesion you must follow general rules: thoroughly clean in advance, degrease well and dry the areas to be joined. And one more thing: the thinner the adhesive seam, the stronger the joint.

Overview of glue varieties.
BF:
Several formulations are produced under this brand, which are distinguished by digital markings. The higher the number in the marking, the higher the ductility and the lower the strength. BF-2 is suitable for fastening rigid structures that are not subject to bending and vibration. BF-4 is more elastic, but the strength of the adhesive seam is slightly lower than that of BF-2. Which type is best to use depends on your tasks.
Technology: 1 hour is allowed for the first layer to dry. Then apply the second layer, let it dry for 10 - 20 minutes and press both parts tightly against each other. Note that BF glue is functional and resistant to high humidity and to most chemical influences. Disadvantage: contains aldehydes and phenol, therefore it is not approved for use in the production of dishes and children's toys.

Polyvinyl acetate (PVA):
This species has long been widely known; has various modifications. To work with wooden products, you can use PVA-MB (universal) or PVA-M (super glue). The latter is considered the highest quality due to its higher viscosity. Suitable for expensive and critical operations.

The main advantage is fire safety. Allow a day to dry. The surfaces to be bonded should be thoroughly degreased.

"Moment":
"Moment" is known as a universal strong glue. Among its varieties there is a specialized one - “Moment Joiner”. Distinctive Features of this brand are:
quick setting - 10 -15 minutes at room conditions;
heat resistance (you can, for example, fix the veneer to the base with a heated iron);
special strength;
color constancy.
The disadvantages include insufficient water and frost resistance.

Carpentry:
There are two types - bone and flesh. The first is made from animal horns, the second is made from the underside of raw animal skin. Of the two varieties, bone is considered the best. It goes on sale in the form of granules, grains or flakes.
When preparing, the dry fraction is soaked in cold water, then cook in a water bath at a temperature of about 70 degrees, stirring thoroughly until complete dissolution occurs. It is used in the form of a warm liquid mass. It is better to use immediately after dilution.

Epoxy:
Made on the basis epoxy resins, and consists of two components - resin and hardener. Suitable for any material, fills cavities well and smoothes out unevenness. Therefore, it is especially convenient for restoration work. Is a dielectric. It is not affected by water, grease, oil, or surfactants found in any cleaning products. It hardens very quickly, and it will be impossible to correct anything after hardening.

Casein:
It is resistant to moisture and elevated temperatures. It is of natural origin (it is based on milk protein) and does not contain any harmful impurities. Completely sets in 20 hours.
Disadvantages include the ability to change the color of glued wood. Sometimes spots appear that darken over time. The finished solution can be stored for no longer than 2 - 4 hours, and it cannot be resuscitated.
Expert tip: The degree of water resistance of the glue is easily determined by the packaging markings. It is indicated by the letter “D” and a number: 2 – low, 3 – good, 4 – very high. However, class D4 is very expensive, and its use must be justified.

Polyurethane:
Very good, but the most expensive choice. Indispensable in cases where it is necessary to provide a critical connection or create a multi-layer structure. The adhesion will be extremely strong, impervious to sea and chlorinated water.
Polyurethane adhesive for gluing wooden items does not react to aggressive chemical environments and ultraviolet radiation. In short, if you need to operate under extreme conditions, including significant mechanical load, this is the best option.

Heat Resistant:
Necessary in cases where wooden product will be fired; For example, gas burner. The use of adhesive with improved thermal properties guarantees that the surfaces connected with it will not disintegrate even when exposed to very high temperatures.

As we see, even so detailed review all kinds of adhesive compositions are unlikely to give a definite answer to the question: “Which glue is best for wood?” Probably the one that will cope with a particular task in a particular case better than others, and at the same time will be affordable for you. If possible, buy glue from two different types and try each one in turn. This way you can choose the most suitable option for your carpentry work.

More and more different options for gluing wood species are appearing on the modern market. Thus, the question arises - how to choose the right glue for wood? In order to accurately answer this question, it is necessary, first of all, to determine the type of surfaces themselves that we will glue and the purpose of the glue itself. In this article we will try to tell you how to properly glue wood to wood and other materials.

What glue to glue wood with, which one is best?

There are various options similar glue:

– PVA glue for wood.

We all know the white, translucent glue that instantly “grabs” the bonded surfaces of any type of material. We have known it since school, when in fine arts lessons the teacher suggested using PVA.

Why PVA? It is one of the few “fast” adhesives that bonds surfaces within twenty minutes. Moreover, when it comes to gluing wood species, a completely similar glue hardens within 24 hours. Accordingly, within a day the surfaces will be firmly glued, and it will be possible to create various types loads

– BF series.

There are various options for BF glue, each of them has its own number. The most popular are BF-2, BF-4, BF-6. If you reach a certain temperature - up to 80 degrees - you can speed up the “setting” up to fifteen minutes, and at normal room temperature This substance will firmly glue the tree in an hour.

– “moment” for a tree.

Moment glue is the most common brand of glue for various construction-related tasks. But we wonder - what is the best glue for wood? In accordance with our request, the Moment manufacturers produced a special substance, Moment glue for wood. They can glue absolutely any surface.

If our task is to answer the question: what glue is best to glue wood to wood, then “moment” answers this and other questions related to gluing wood to any other material.

– heat-resistant glue.

It is most popular for those types of work, including carpentry, where wood is exposed to various thermal influences. It does not collapse and does not peel off surfaces even at high temperatures.

In this case, many are racking their brains: what kind of glue should they use to glue the wood if it will subsequently be exposed to heat? The answer to this question is heat-resistant glue. Unlike similar ones, it does not crumble or collapse on its own, and does not destroy the structure of the glued surfaces under thermal influence.

– casein glue

This glue, unlike the previous one, is intended to be a waterproof glue. That is, the treated surfaces may be exposed to large quantity moisture along with high temperature. Among the known adhesives, this is one of the most popular; it hardens completely within 20 hours, and “setting” occurs in 8 hours.

– wood glue

Wood glue is a solution intended for gluing and joining various objects made of wood or plywood, fiberboard. To create this glue, two types of compositions are used: hide and bone. The first type is considered to be the most effective, and the seams resulting from its use become as strong and durable as possible. In this case, much depends on compliance with the glue preparation technology.

When gluing surfaces using this solution, you need to apply it to the main surface once, and twice to the end surfaces. After application and gluing, the surfaces of the products to be glued should be pressed firmly against each other only after a few minutes, then the wood glue will not come out. In order for the seam to be as smooth and durable as possible, the thickness of the glue should not exceed 0.1 - 0.15 mm.

– epoxy glue

Epoxy glue has gained great popularity because, in addition to wood, it can glue any known materials, can perfectly smooth the surface, and quickly fills any cavities. When the mixture dries, it simultaneously acquires the ability to insulate electricity and is immune to many chemically aggressive substances; it is not affected by fat, oils, or surfactants.