Fields of application of polyurethane foam. There are 7 wonders of the world, but one of the unusual materials in modern chemical science is the creation of a new polymer, which became known to the world as polyurethane foam. I make it from petroleum products using a special chemical treatment. The material has a cellular structure, and each of them contains a gas bubble. By setting different proportions of raw materials, polyurethane foams with different mesh sizes can be obtained.
It also differs by the wall thickness of the cells. The result is soft and hard polyurethane foams that differ in elasticity and strength.
This process is nothing more than the merit of German scientists who were able to add an incredible result under the leadership of Otto Bayer. Indeed, thanks to a novelty in technical materials, which differs from others and has a lot of advantages, we have received many fields of application of polyurethane foam, which affect different areas of human activity.
The types of polyurethane foam depend on the strength of the cells:
Rigid polyurethane foam is used in construction, building insulation, repairs and other situations. Much research has been done on the characteristics of the material, and especially on artificial aging.
So, the result cannot but rejoice - the service life is at least 50 years. Contact with strong mineral acids and organic solvents should be avoided for successful use. The material is resistant to oil and water.
Interestingly, the polymer was discovered in 1937, but its triumphant rise and gaining popularity took place around 1960. Rigid polyurethane foam has more than 30 modifications that differ in technical characteristics and are used in various fields.
Among the huge number of foamy polymers, it is difficult to choose the second such material that will be combined in so many advantages to itself:
The characteristic features of the use of polyurethane foam depend on the size of the cells from which it consists.But still, in comparison with other heat insulators, polyurethane foam is the leader in all respects, and especially in thermal conductivity, since even mineral wool is inferior to it in this. Noise absorption can be determined by the thickness of the insulation layer, its elasticity, air permeability and damping properties.
The ability of polyurethane foam to trap sounds depends on the frequency of sound vibration and the hardness of the material. For better protection against noise, it is advised to use a semi-elastic version of polyurethane foam.
Polyurethane foam is also a chemically resistant material, and by this indicator it could overtake even the vaunted polystyrene foam. PU foam can withstand corrosive chemical vapor (in normal concentration), and will not be destroyed by alcohol, oil, gasoline, and is also resistant to ketones, ethers and dilute acids. A layer of polyurethane foam applied to the metal will perfectly protect it from rust formation on the surface.
The effectiveness in this case largely depends on the type of material.
PPU has a fairly high resistance to moisture. It largely depends on the recipe according to which the polyurethane foam was made. So, the higher the density, the less the material will absorb moisture. If you want to increase the level of resistance, you can use special substances called water repellents.
For example, when castor oil is added to the composition of polyurethane foam, you will reduce water absorption by 4 times!
The use of polyurethane foam is quite wide and due to the fact that this substance has a low degree of combustion. The use of various additives makes it possible to increase the level of fire resistance. Not everyone can afford to change the chemical formula, but adding phosphorus compounds or halogens to the recipe is much easier and more profitable. This will make it possible to obtain non-combustible material, while not increasing the cost of the material too much. This is a fairly reasonable option for premises where the risk of fire is too high, namely, for industrial premises.
The density of different types of polyurethane foam is different due to the fact that the production technology is different. Material with good specific gravity characteristics, up to 80 kg per 1 m 3 , is more expensive in cost, while at a lower density the price is lower.
The manufacturer claims that the service life is only 30 years, although in fact this figure is much higher. Japanese and American experts are actively studying samples of polyurethane foam, which was used in the construction of houses in the 70s. As a result, they concluded that all the material that was taken as a sample from the roofs and walls remained unchanged.
The indicators of chemical resistance and technical heat-insulating properties remained in their original state.
Since it is the safest and most environmentally friendly in terms of environmental and technical characteristics after curing material.
Please note, that during the initial use of such an unusual structure of material it was planned to use polyurethane foam products for the interior, and there were no serious plans for the future.
The advantages in terms of technical characteristics include the fact that the material has an excellent ability to "stick" to any surface, and this does not depend on the materials from which they were made, and the shape of the coating. Due to the properties of sprayed polyurethane foam, it can be applied to any material - wood, concrete, glass, metal and no matter how the structure is located - vertically or horizontally.
In addition, polyurethane foam has high adhesion and is easy to use, it does not need to be fixed to the surface and processed before being applied to the surface.
Due to its low weight, the use of polyurethane foam simplifies repairs - it does not make the structure heavier, which is a significant advantage in construction. PPU tolerates both low and high temperatures, which makes it possible to use it for indoor and outdoor treatment, both in residential and industrial premises.
Unlike other heaters (sheet or panel), polyurethane foam does not form cracks and seams that need to be repaired. It perfectly fills the space around the structure, which is insulated, and makes it possible to seal everything, including those places that are inconvenient to seal with other materials.
During storage and transportation, PPU is cheap, since compact initial elements are used for its manufacture. According to its characteristics, polyurethane foam is excellent for upholstered furniture, and it is often used to create filler for sofas, armchairs and pillows. Recently, foam rubber has been used much more often than cotton padding and cotton wool. Everyone knows this material, and it can be used for various household needs.
But, the ideal material does not exist, at least for now.
In addition to the advantages, rigid polyurethane foams have some disadvantages:
The technical characteristics of the PPU will make it possible to use it further in many areas of human activity.
Posted By: Work Style |08, Nov 2020
Posted By: Work Style |08, Nov 2020
Posted By: Work Style |05, Nov 2020
Posted By: Work Style |02, Nov 2020
Posted By: Work Style |02, Nov 2020