Fire resistant foam is a type of foam that has refractory and fire-resistant properties. Thanks to these qualities, it is used in special facilities where strict adherence to fire safety requirements is required. Foam has special characteristics that require specific rules of use. This article will tell you about the types of polymer, features of application and criteria for choosing a material.
Fire resistant foam: characteristics and properties
A specific substance with fire-resistant properties was invented by a group of scientists led by Otto Bayer in 1947 quite by accident – during experiments with polyurethane. Then it was difficult to assume that polyurethane foam will find wide application in construction after 70 years.
Initially, such materials were used in industrial construction as insulation boards. In the 70s, the British company “Royal Chemical Industry” invented polyurethane foam cylinders, and their serial production began in the 80s in Sweden.
The main properties of refractory foam are heat resistance and fire resistance. Now it is quite often used for finishing slopes in openings during the installation of fire doors. The non-flammable substance, which fills the cracks, creates an airtightness and, in the event of a fire, prevents the penetration of smoke and burning into the room. Such requirements are consistent with fire safety regulations.
Fire-resistant foam is not much more expensive than similar products that are used in installation and finishing works, therefore it is often used not only for its intended purpose, but also for other construction needs, even when high fire resistance requirements are not imposed on this object.
Composition of fire resistant foam
High refractory and technical characteristics of the polyurethane foam ensure its composition, which includes:
- catalysts accelerating the expansion, which provides for the possibility of using foam even at sub-zero temperatures;
- foaming agents that affect the speed of solidification and the degree of foam porosity;
- stabilizing components that ensure uniform distribution of foam on the surface;
- gas expelling the substance from the vial.
Helpful advice! When buying fire fighting foam, it is imperative to make sure that you have a certificate of conformity. This document confirms its refractory properties.
The main and, perhaps, the only requirement for this type of fire-fighting products, provided for by the regulatory document, is the level of resistance to fire.
The document discusses the methods of testing building structures, materials that are used in the construction and decoration of structures, for fire resistance. Thus, fire-resistant assembly foam has a fire resistance limit. This parameter indicates that the substance has been tested for integrity and the ability to maintain thermal insulation properties under intense fire exposure. The corresponding indicator for products presented on the domestic market depends on their type and ranges from 60 to 360 minutes.
Technical characteristics of refractory foam
In almost every type of construction work, whether it is the laying of engineering networks or cable communications, the formation of holes is provided. In the event of a fire, unsealed openings become a direct path of fire spreading into adjacent rooms. In order to avoid disastrous consequences, fire-fighting plaster or special basalt material is used in the installation. In order to directly protect communications and prevent the advance of fire, flame arresters and refractory couplings are used.
Currently, along with the listed traditional materials, fire-resistant foam is used, which has already proven itself to be excellent. This is evidenced by the characteristics of the polyurethane foam. The main ones are:
- High fire resistance (up to 360 minutes). This suggests that the foam is comparable to a firewall.
- High adhesion – adheres well to almost all building materials. This substance is combined with brick, reinforced concrete, metal structures, cinder blocks, cement mortar, gypsum, glass, plaster and even ceramics used in wall decoration and flooring.
- The foam does not run off when applied to the wall.
- The use of an assembly substance allows you to do the job quickly and does not require special qualification skills.
- The material easily penetrates into openings and openings and spreads throughout their volume, fills all cavities well.
- The foam hardens quickly at temperatures from -18 to +35 ° C, which shortens the time it takes to complete the work.
- The material does not have secondary expansion properties.
Performance characteristics of polyurethane foam
Polyurethane refractory foam serves for a long time and reliably. It retains its characteristics in conditions of low air humidity. Unlike other substances, foam does not crack when exposed to dry air. Conversely, in rooms with a high level of humidity, it does not swell, and fungi and mold do not form on it.
Helpful advice! When choosing a product, you need to decide on its intended purpose. Sealing joints in ceilings at the intersection of a chimney with a stove, fireplace or boiler requires a more reliable material.
Refractory foam serves reliably even in unheated warehouses, ancillary structures, engineering and industrial premises. Due to the wide operating temperature range, which ranges from -40 to +100 ° C, the substance can be used in different climatic conditions, even in areas with significant temperature fluctuations.
Due to its high thermal insulation properties, the foam does not allow air, heat, as well as smoke and gas mixtures to pass through. This quality is very important in terms of fire safety. A surface protective film forms on the material very quickly – within about 10 minutes. 65 liters of foam comes out of one 750 ml bottle under pressure.
Best polyurethane foam: categories of use
When choosing a mounting fire-fighting foam, the main attention should be paid to in which rooms and in which areas it is planned to use it. In this case, it is important to take into account the possibility of periodic heating of the structure and the likelihood of a fire. These qualities affect the typical and species differences of the foam.
Depending on the possibility of using the substance at subzero air temperatures, fire-resistant foam is divided into application categories:
- at a temperature not lower than +5 ° C;
- at temperatures from -5 to -10 ° C.
Given the presence of active components, the foam is divided into one- and two-component. One-component refractory foam cures when exposed to water. Therefore, when using it, the surface is pre-wetted. Two-component fire-fighting foam is capable of curing without moisture. The use of such a substance is possible even in winter.
Manufacturers, in order to ensure fire resistance, add special chemicals to the foam – fire retardants. Their names and proportions are not disclosed for commercial purposes. Polymerization of refractory foam occurs as a result of chemical reactions and when exposed to air and moisture. Products from different manufacturers differ in technical characteristics.
Polyurethane foam: instructions for use
Information on how to use polyurethane foam is posted on the cylinders. On the Internet, you can find many useful tips with visual lessons that demonstrate the use of foam in the process of performing various installation work. The main stages of using a substance can be summarized in several points:
- The container must be heated in hot water and shaken well. This will mix the gas and liquid components and maximize the foam yield.
- Next, the balloon is pushed onto a tube or mounted on a pistol.
- Before applying the foam, the surface is cleaned of dust and dirt and moistened with water.
- Apply foam to the surface. For this, it is necessary to calculate the dosage of the foam coming out of the cylinder. A pistol will help with this. The bottle should be held with the valve down while applying the substance.
- Foam drying stage. This usually takes 6-8 hours. The duration of the process depends on the volume of the substance and can be up to 12 hours.
- After the foam dries, the excess is cut off with a sharp knife or file.
Polyurethane foam is a material that is sensitive to ultraviolet radiation and degrades under its influence. Therefore, the polyurethane sealant used outdoors must be coated with a special solution after drying.
How to clean polyurethane foam
After using polyurethane sealant, the question arises: how to wash the polyurethane foam? It turns out that there are many answers and helpful recommendations that depend on your particular situation.
Helpful advice! To avoid the dilemma of how to wipe the polyurethane foam off your hands, it is important to prevent the substance from getting on the body. To do this, you need to work carefully, using special clothing and protective gloves.
Sometimes, even when using gloves, the sealant gets on the skin, then you have to decide how to wash the polyurethane foam from your hands. A special solvent, which is used to flush a professional pistol, will help to get rid of the substance.
In solving the problem, than to wipe the polyurethane foam from the skin, available means will help. You can wash off the substance with kerosene or remove it with a napkin dipped in heated sunflower oil. But for this you need to be patient and hold the product for about half an hour on the skin. Ordinary table salt will also help if you gently rub the dirty places with it, as well as the Dimexide solution, but it is better to use it to remove polyurethane foam from clothes. As a solvent, this drug will help to quickly get rid of contamination.
If the sealant is dry, then you will not have to wash, but to clean the foam from the clothes. How to do it? First, the building material will have to be removed manually. Further, you can use the above solutions.
Before wiping off the polyurethane foam from the door or other surface, it is better to wait until it hardens, and only then carefully remove the dried material with a thin clerical knife.