Polyurethane glue has gained popularity due to its versatility. The scope is not limited to household repair of products and the joining of dissimilar materials. It is also used for decoration and decoration, in the production of building and finishing materials. High strength and adhesion characteristics allow bonding wood, plastic, metal, fabric and mineral materials.
Features and Benefits
Polyurethane adhesives differ from other water-based adhesives in the principle of hardening. When interacting with a hardener or moisture from the ambient air, polymerization occurs with the formation of a film. During a chemical reaction, foaming occurs due to the release of carbon dioxide.
The versatility of polyurethane lies in the versatility of its use. Suitable for bonding natural and artificial materials in various combinations. Connects plastic, fabric, wood, metal, stone, ceramics, glass, rubber, cardboard, polystyrene.
When using a polyurethane composition, the following advantages are distinguished:
- durability of the connection;
- high adhesion to smooth and porous materials;
- moisture resistance;
- tightness of the glue seam;
- resistance to high temperatures;
- frost resistance;
- the curing process allows achieving high bond strength;
- chemical resistance to oils, acids;
- long working time.
Polyurethane cannot bond polypropylene, polyethylene, silicone and Teflon coatings. Surfaces with oil and wax deposits will not be able to adhere properly. The components of liquid glue can irritate mucous membranes and skin, therefore, safety measures must be observed during work.
Properties and characteristics
Synthetic polyurethane adhesive consists of film-forming polymers. Its composition can be supplemented with viscosity regulators, stabilizers, resins, surfactants, crystallization accelerators. Isocyanates and hydroxyls are used for hardening. The main difference from formulations based on aqueous dispersions is the ratio of solids. In polyurethane mixtures, the solids ratio is higher.
The glue seam is operated from -40 to +120 degrees. High bond strength of smooth, rough, porous materials is ensured by following the application steps. Bonding should be carried out at least +15 degrees. The polyurethane compound exhibits thixotropic properties, therefore it is imperative to adhere to the recommended drying time. Since the glue is moisture resistant, it is not affected by bacteria and mold..
Consumption of glue for continuous application is from 500 to 1000 g per 1 m2. The amount of adhesive used varies depending on the type of material and the thickness of the applied layer. With spot application, an average of 150 g is spent. When applied by zones, the consumption may vary depending on the distance between the stripes..
The color and viscosity of the glue varies depending on the purpose and composition. For gluing wooden parts, the color of the adhesive changes from amber to brown. Often polyurethane mixtures are produced in white, gray, yellowish colors. The universal adhesive is produced transparent. The consistency is liquid and gel-like.
Adhesive mixtures based on polyurethane differ in packaging volume. For domestic use, the glue is poured into tubes of 20, 30, 50, 125 and 310 ml. Large volumes from 750 g are packed in cans or plastic cans or cylinders. For private construction and repair, it is advisable to purchase buckets from 2 to 20 kg. For industrial needs, the polyurethane composition is packed in barrels of 200 kg and cubes.
Polyurethane-based glue is used for internal and external work, as it is not afraid of moisture and frost. Polyurethane is used for the production of flexible stone, where graphite, limestone and marble chips are glued to the fabric base. The polymer composition is used to connect the details of the window profile, PVC edges, lamellas, used for gluing glass into the frame.
Used in professional construction and improvement of children’s and sports grounds with modern coatings. The plot is glued with artificial turf grass or special rubber mats. Polyurethane is a binder in the production of tiles and coatings from rubber and rubber crumb. Even ordinary foam sponges stick together with this product..
The adhesive composition was widely used in the production of sandwich panels. Fibreboard cladding is bonded with mineral wool or polystyrene core using polyurethane adhesive. During curing, SIP panels are under load with further drying.
In everyday life, the use of polyurethane glue is justified for all types of repair work and repair of various products.. It is indispensable for attaching skirting boards, cornices and moldings to walls and ceilings. Suitable for repairing wooden moldings, plastic parts. It is used as a glass glue for gluing ceramics, plexiglass, porcelain. Indispensable in the repair of garden and home furniture made of wood and metal.
A special polyurethane shoe composition is produced for self-gluing of soles, heels and insoles. It reliably holds leather, fur, suede, fabric with different types of soles. The adhesive is suitable for repairing rubber boats, PVC pools, inflatable rings and balls.
In construction work, polyurethane is used as a tile adhesive for fixing porcelain stoneware, mosaics, ceramics, decorative stone, marble to any base. Its use for laying ceramic tiles is recommended by manufacturers and craftsmen. The adhesive base does not flake off, it tolerates moisture and adverse outdoor conditions well.
A special polyurethane-based parquet adhesive is produced, which is intended for arranging a wooden floor. Suitable for gluing mosaic and end parquet, solid wood parquet boards and engineering multilayer boards, plywood, laminate. The heat-resistant properties of polyurethane make it possible to use in underfloor heating systems.
When building a house from aerated concrete, polyurethane adhesive foam is used as a masonry material. Laying aerated concrete blocks on foam serves as an alternative method for the construction of walls. Foam glue is also suitable for bonding gas silicate blocks and aerated concrete. The minimum thickness of the seam reduces material consumption and excludes freezing of the structure along the cold bridges.
For fixing polystyrene foam, foam glass, polystyrene foam, polystyrene foam and other artificial plate heat-insulating materials, special polyurethane glue in a cylinder is used. The ready-made glue foam allows you to evenly and quickly distribute the composition using a nozzle. The mixture allows the sheets to be adjusted within 10 minutes before setting. And also an adhesive mixture for heaters is suitable for sealing joints in thermal insulation, replacing ordinary polyurethane foam.
Polyurethane adhesive is polymer in structure. Depending on the composition, one-component and two-component polyurethane glue is distinguished. One-component mixture is produced ready-made, the polymerization process takes place in the presence of water. The moisture-curing compound foams better when the air humidity is at least 60%. During the reaction, the volume increases and the expanding composition comes out along the edges of the seam.
Two-component product consists of two components that are mixed before gluing. You cannot make homemade glue, because when the proportions of the hardener are changed, a chemical reaction and hardening will not occur. A quick-drying composition is produced, which is processed by hot temperatures from 80 to 110 degrees.
Universal one-component contact adhesive for bonding various material combinations. The polyurethane compound is capable of replacing heat-resistant automotive sealant for repairing car parts and anti-corrosion protection. To fix the heaters, use a special polyurethane assembly glue, similar to foam.
Prepare the work surface before applying the PU adhesive. The entire area must be cleaned of dust, dirt and debris. The working area is cleaned of old remnants of plaster, paint, cement. The key to successful adhesion is to degrease the surface, as it is necessary to get rid of traces of oil and grease. You can clean the area of dirt with thinner or alcohol..
Security measures must be taken. Provide ventilation in the room and protect hands with disposable gloves.
The glue is applied in a thin layer, evenly spreading over the surface using a plastic spatula or improvised means. Both sides are coated with polyurethane with the addition of solvents. This feature is indicated in the instructions. On a porous material, the composition is applied in two layers with a break of 2-5 minutes. Spray adhesive foam is distributed on the base in strips, along the perimeter at least 8 cm from the edge. The distance between the strips can be changed from 10 to 25 cm.
After applying the glue, after 5-10 minutes, it is necessary to connect the prepared surfaces, pressing firmly. Roll with a roller if possible for a firm grip. To accelerate the setting, the adhesive side is sprayed with water. Wet method increases the rate of chemical reaction.
The next method of gluing improves the moisture-resistant properties of the seam and accelerates drying. The polyurethane layer is allowed to dry for 20 to 90 minutes according to the instructions. The glue surface is heated with a hairdryer for several minutes, then connected and placed under a press for 5 minutes.
How to dilute and wash?
When mixing a two-component polyurethane mixture with a hardener, the addition of additional ingredients is not allowed. To improve the heat resistance and adhesive properties of the composition, you can use the Desmodur activator, adding no more than 6-7% of the total mass of the glue. The finished one-component composition must not be diluted with water or alcohol. If the glue is thick, hard to spread over the surface, then it can be diluted.
There is a thinner on the market for polyurethane adhesive, which is used to adjust the viscosity. But you can also dissolve with acetone, ethyl acetate, methyl ethyl ketone. When interacting with toluene, the composition swells. All grades of polyurethane adhesives can be effectively diluted with a solvent mixture of acetone, toluene and MEK.
After work, the tool must be cleaned immediately, without waiting for drying. Contaminants are removed with a rag soaked in acetone or any solvent. The remnants of the product that have got on clothes and other surfaces are washed off with acetone. Cured adhesive can be removed mechanically.
How much dries?
The setting time of polyurethane glue depends on the additional components in the composition, on average from 20 minutes to 1 hour. While the glue is liquid, it is necessary to firmly press the surfaces to be glued and fix for a few minutes. If possible, you can place the product under the press for 1 hour to ensure a snug fit. The closer the parts are to each other, the higher the quality and strength of the glue line. If part of the adhesive has emerged on the surface after hardening, it is necessary to remove the excess mechanically.
Full curing occurs within 24-48 hours, during this period strength is gained in the glue line. At this time, the glued product should be at rest, no mechanical action should be applied. Drying time depends on the ambient temperature. If polymerized with a hot method, then full cure will take place after 4 hours..
How to store?
Unopened unused packaging with polyurethane composition should be stored at temperatures from +10 to +30 degrees, away from heating appliances and direct sunlight. The shelf life varies from manufacturer to manufacturer, can be from 12 to 24 months from the date of manufacture.
Use polyurethane glue no later than six months after opening the package. Moist air penetrates into an open container, part of the mixture freezes. The cap is screwed on tightly to restrict the access of moisture and air. To prevent blockage of the hole, the tube must be stored vertically, placing it on the lid..
The volume of the market for polyurethane adhesives in Russia is divided approximately equally between domestic producers and imports. Imported products are represented by Italian, American, Turkish manufacturers. Many companies are engaged in the production of polyurethane adhesives in Russia, focused on application in production and in everyday life..
Italian company Adesiv launches Pelpren PL6 two-component adhesive based on polyurethane and epoxy resin for professionals. It is designed for laying parquet and solid wood on any surface. Provides a non-shrink elastic and durable adhesive seam.
The American company Bostik produces two types of polyurethane mixtures for gluing parquet – one-component Tarbicol PU 1K and two-component Tarbicol PU 2K. One-component composition is packed in packs of 7 and 21 kg, Tarbicol PU 2K is packaged in 5 and 10 kg.
The international company Dow Chemical Company produces Insta-Stik universal polyurethane adhesive in 750 ml and 10.4 liter cylinders. It is designed to attach any kind of insulating material to vertical and horizontal surfaces..
Turkish manufacturer Duayen has been supplying polyurethane-based binding adhesives to the Russian market since 2001. Duayen А-121 and А-338 is used for coatings made of rubber, concrete, wood, metal, rubber. Adhesive for sandwich systems A-138 is used for the manufacture of decorative street coverings on sports and playgrounds, walking paths. Two-component thixotropic polyurethane compound A-118 is designed for gluing any kind of parquet. A-128 grade is used in shipbuilding and furniture production. Duayen Р-244 glues foam sponges, fabrics and fibrous materials.
The German brand Henkel with production facilities in Russia produces polyurethane adhesives for industry and household use. The four varieties of Henkel Technomelt PUR are designed for window profile bonding and lamination. Universal contact compounds based on polyurethane brand “Moment” combine dissimilar materials from glass, plastic, rubber, ceramics, fabric, wood, leather. Available in tubes of 30, 50, 125 ml.
Purtis polyurethane adhesives plant with production facilities in Moscow and Almaty. It produces adhesives for PVC and SIP sandwich panels, construction timber, parquet. Purtis 2K. Sport is used for bonding crumb rubber, sports mats, artificial grass. Purtis SE brands. 10, SE. 15, SE. 60 are used in the production of foam sponges. One-component mixture adheres natural and artificial fibers, textiles, cardboard, fiber, foam rubber to dissimilar polymer surfaces.
Since 1991, OOO NPF Adgeziv has been producing polyurethane adhesive products. The assortment includes more than 10 types of adhesive mixture, including two-component adhesives of the Vilad brand, one-component compositions of the ADV brand.
JSC “Anles” is engaged in the production of adhesive polyurethane products for industrial and household use. Polyurethane and PvcFix glue based on urethane rubber is intended for gluing polyurethanes, thermoplastics, PVC, metal, glass, leather. Products based on natural rubber “Rubber” and “Gummi” are used in the manufacture of footwear, for the repair of leather goods, rubber-fabric products, gluing paper and cardboard. On the basis of chloroprene rubber, the brands “Universal”, “Radical”, “88”, “Shoe” are produced for a wide range of works. Available in 40 ml tubes, 1 l cans, 17 kg buckets.
ATK-Alliance LLC produces polyurethane adhesives ATK-3M, ATK-8M for sandwich panels, ATK-3D for door and window production, ATK-10 for shoe production, gluing plastics and PVC, ATK-19 glues foam rubber to any bases.
LLC “Kleon” produces industrial adhesives 704 and 501 for shoes.
CJSC “Blockform” is engaged in the release of polyurethane chemical products. BFM-1 glue glues elastic materials, BFM-11 binds crumb rubber coatings, BFM-20 is used for the manufacture of sandwich panels, BFM-22 is designed to protect engineering structures from climatic influences.
The popular Desmokol shoe glue is produced in Ukraine. NPP Rogneda LLC produces universal multifunctional polyurethane compounds “UR-600”, “Master”, “88” packaged in 0.75 l cans and 20 l buckets.
Firm “Neomer” – a manufacturer of polyurethane binders and adhesives for the formation of outdoor surfaces and tiles from rubber crumb.
Soudal is a major supplier of polyurethane aerosol foams.. There are 7 types of compositions for fixing various materials in the assortment, the balloon consumption is 12 m2.
Polyurethane glue “Slavyanka”, produced by the company “Rastro”, is intended for gluing thermal insulation to any substrates.
About polyurethane glue for shoes – gluing technology, see the following video.