| WHAT ARE BROMINATED FLAME RETARDANTS? WHAT ARE THEY USED FOR? The introduction of 'new materials' Today, we live in a modern society where we are surrounded by many consumer products, made out of flammable materials such as oil-based plastics and synthetic materials. Brominated Flame Retardants (BFRs) are chemicals commonly used in many domestic and industrial appliances and equipment such as computers, TV's, mobile phones, furniture, insulation boards, mattresses and many more others. 90% of electrical and electronic appliances contain BFRs. BFRs are used to increase their resistance to fire. Flame retardants give up to 15 times more time to scape when there is a fire. BFRs are also used in textiles for upholstered furniture. For an overview of the applications of the different brominated flame retardants, please click here. Protecting peoples' lives
Providing Safety in the Home
The development of flame retardants has made possible the safe use of a wide range of materials and consumer products. Flame retardants are chemicals which are added to materials, either during or after manufacture, and because of their chemical nature reduce both the chances of the material igniting and, if they do, they slow the rate of combustion. The use of flame retardants in the manufacture of electronic equipment, upholstered furniture and textiles has been shown to save lives from fire.
Similarly in the case of televisions, the introduction of a higher fire safety standard in the US for television enclosures has led to a 73% decrease in the incidence of fires involving televisions.
Providing Safety in Public Places Flame retardants are not only important in the home, they also ensure the fire safety of many public places. In modern facilities such as cinemas and theatres, it is almost inconceivable that the textile furnishings would not be flame-retarded. The same applies to many forms of transport, including cars, airplanes and train furnishings. But flame retardants are perhaps most important in protecting people where they are at their most vulnerable, in schools, homes for the elderly, and hospitals.
How do Flame Retardants work? Fire is a chemical reaction between oxygen and a fuel, triggered by an ignition source or heat. Brominated Flame Retardants (BFRs) are in many circumstances the most effective chemical to prevent ignition or a fire from developing. Basically, BFRs inhibit this chemical reaction from taking place and in that way prevent a fire from developing.
When Flame Retardants started to be used Chemical flame retardants have been used since Roman times when they were used to prevent seige towers from catching fire. The first patent on a flame retardant was British Patent 551 to Obadiah Wilde in 1735 to flame retard canvas for use in theatres and public buildings. In the plastics industry they were first used in cellulose nitrate which was extremely inflammable. In the early '70s, the increasing use of flammable materials such as plastics in electrical equipment or synthetic fibres in sofas and curtains led to the wider use of flame retardants. Manufacturers of furniture and appliances began to move away from traditional materials such as wood and metal towards new materials such as plastics for appliances and polyurethane foam and fibre-based fillings for furniture. While these new materials provided many benefits, they had one problem - they were far more combustable than the materials they replaced, which meant they would both catch fire more easily, and once alight, combust more rapidly, giving people little time to escape. Flame Retardants are able to contribute greatly to reducing the risk of fires providing safety in the home and in public places.
Different types of flame retardants There are a number of different "families" of flame retardants:
The choice of a given flame retardant frequently depends on the type of application. Their suitability is subject to variables such as the material to be flame-retarded, the fire safety standards with which the product must comply, cost considerations and recyclability.
Halogenated flame retardants Bromine, chlorine, fluorine and iodine, are the elements in the chemical group known as halogens. The word halogen derives from Greek, meaning 'salt-former', because these elements are commonly found in nature reacted with metals to form salts. For example, sodium chloride, or table salt, is the most common example of a halogen salt. Halogenated flame retardants act in the vapour phase. That is they actually interfere with the chemistry of the flame to prevent it from propagating. Chlorine and bromine are both effective in this role. Fluorine is too stable to be an active flame retardant and iodine based compounds are too unstable to be flame retardants. Chlorinated flame retardants are mainly used in plastics. They offer good light stability but compared to brominated flame retardants, higher quantities are needed for achieving comparable flame retardancy. Brominated flame retardants are often the most effective flame retardant when both performance and cost are considered.
Why is bromine effective as a flame retardant? In general the stability of bromine in a typical flame retardant molecule means that they can offer the highest activity as a flame active retardant as well being very cost effective. The choice of flame retardant systems for any particular application will depend on how the material decomposes in a fire, as well as the physical properties required. BFRs, because they act in the flame, can be used in just about every application, indeed in some plastics and uses they may be almost the only choice. The fact that BFRs are particularly efficient on an addition level basis means that frequently they may have less impact on the physical properties of a plastic than other systems. There are also a wide range of BFRs available. These enable a formulator to select the optimum product to balance cost with physical properties, temperature resistance, processing characteristics and all the other important characteristics a particular end use may require.
Different types of Brominated Flame Retardants (BFRs) Among the many BFRs used in the world the main commercial BFRs are the following:
Each of these Brominated Flame Retardants have very different properties.
Brominated Flame Retardants (BFRs) and the environment The important contribution of BFRs in protecting our environment is often not known. For instance, according to a life cycle assessment (LCA), the use of plastics flame retarded by BFRs reduces dramatically the emissions of toxic substances such as polyaromatic hydrocarbons (PAH) and dibenzodioxins and furans.
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