Chlorine-based flame retardants

Examples of foaming agents are sodium bicarbonate, ammonium bicarbonate and nitroso compounds. Especially, when dinitroso-pentamethylenetetramine is used, foaming aids can be added that accelerate the decomposition and reduce the decomposition temperature. This is achieved, for example, with salicylic acid, or with urea. Various chlorine and bromine flame retardants can be used as halogen-based flame retardants, e.g., tetrabromobisphenol A de-rivates. 

A common disadvantage of chlorine-containing flame retardants is that they have to be added in quantities, which in turn decrease mechanical properties of the polymer materials. The same sitnation in terms of large amount that should be added into the base material holds for mineral flame retardants as well (ATH, Mg(OH)2) however, minerals typically improve both flexural modulus (stiffness) and flexural strength of composites. 

Aliphatic halogenated hydrocarbons (Specific CFCs, halon, chlorine-based organic compounds) Specific bromine-based flame retardants Penlachlorophenols... 

A significant advance in flame retardancy was the introduction of binary systems based on the use of halogenated organics and metal salts (6,7). In particular, a 1942 patent (7) described a finish for utilizing chlorinated paraffins and antimony(III) oxide [1309-64-4]. This type of finish was invaluable in World War II, and saw considerable use on outdoor cotton fabrics in both uniforms and tents. 

Flame retardants such as a-alumina trihydrate [14762-49-3] can be added to latex-based foamed carpet backing a combination of antimony oxide [1309-64-4] and chlorinated paraffins is used in dry mbber. 

Paints are complex formulations of polymeric binders with additives including anti-corrosion pigments, colors, plasticizers, ultraviolet absorbers, flame-retardant chemicals, etc. Almost all binders are organic materials such as resins based on epoxy, polyurethanes, alkyds, esters, chlorinated rubber and acrylics. The common inorganic binder is the silicate used in inorganic zinc silicate primer for steel. Specific formulations are available for application to aluminum and for galvanized steel substrates. 

When used purely as an insulator, foam densities can be as low as 0.02 to 0.08 g/cm3. In structural applications the foam s density can rise to 0.4 to 0.7 g/cm3. The use of fluorocarbons as blowing agents has largely given way to more environmentally friendly agents, such as low molecular weight hydrocarbons. We can impart flame retardancy by incorporating chlorine-or phosphorus-based compounds. 

An overview is provided of ongoing risk assessments on halogenated phosphate ester flame retardants in Europe. On the basis of the so-called second and fourth Priority lists on Existing Chemicals (Council Regulation No793/93) three chlorinated phosphate ester flame retardants are selected. The selection is based on their hazard profile, volume and use pattern. The three substances involved are TCPP, TDCP and TCEP (Antiblaze V6 from Albemarle is also involved but, due to confidentiality, is not discussed. An outline is provided from a European point of view on topics such as methodology of risk analyses, data-gaps and worst case approach, industry involvement, downstream participation and possible impact of final report on industry. 2 refs. 

Electrolux is the world s largest producer of powered appliances for kitchen, cleaning and outdoors. They have created comprehensive Environmental Product Declarations (EPDs) for many of their product lines. Information within the product profiles details chemicals that have been banned as well as the percentage and types of materials and how they have improved material choices. Forexample, plastic components do not contain cadmium, lead, mercury or their compounds or chlorinated or brominated flame retardants metal components are not coated with cadmium, chromium, or nickel and metal paints do not contain pigments and additives based on heavy metals. Many Electrolux products are also PVC-free. 

TG-FTIR Vulcanisation [32], ageing characterisation [39, 48], sulphur components in rubber [31], polyurethanes [37], polymer degradation mechanisms [30, 40, 41], identification of base polymers [36, 43, 44], thermal stability [46], grafted flame retardants [47], differentiation of EVA rubbers [45] and AN-NBR rubbers [36, 44], degradation of chlorinated natural rubber [42],... 

The traditional halogen fire retardants used in styrenic copolymers are decabromodiphenyl ether and octabromodiphenyl ether, tetrabromobisphenol A, bis(tribromophenoxy) ethane, ethylene bis-tetrabromophthalimide, and chlorinated paraffins. Actually the octabromodiphenyl ether has been banned on precautionary principles, as will be explained below. The fire-retardant capabilities of the more effective halogen-containing compounds are in line with the quantity of halogen in the final polymer blend, with consideration for the use of synergists. Thus, the practical utility of these flame-retardant compounds (once the issue of degradation temperature is resolved) is often based on their ability to be blended into the polymer and to not substantially affect the physical properties of the polymers. 

In the case of flame retardant silicone elastomer, many ingredients such as silica, platinum, and other flame retardant agents are incorporated into the base siloxane polymer. But there is no need to use the halogenated flame retardant agent, for example, bromine or chlorine compounds. This difference is an advantage of silicones compared with other synthetic polymers in terms of health and safety. 

Special considerations presence of zinc, copper, iron and nickel compounds accelerated dehydrochlorination combination of basic magnesium carbonate and aluminum hydroxide is used as flame retardant and smoke supressant chlorinated polyethylene adsorbs on the surface of titanium dioxide forming a layer 1-20 nm thick depending on the aciii/base interaction parameter of titanium dioxide ... 

Very interesting reactive flame retardants were used successfully in the fabrication of flame retardant rigid PU foams by Solvay under the name of Ixol polyols. These polyols are triols based on epichlorohydrin and brominated unsaturated diol. Ixol polyols have chlorine, bromine and phosphorus in each structure [3, 44, 45]. 

The fire resistance of polyurethanes is based on the introduction of flame retardant compounds including polyols, containing chlorine, bromine or phosphorus in their structure. The polyols containing chlorine, bromine or phosphorus are linked chemically in the polyurethane structure and lead to self-extinguishing polyurethanes, with a permanent flame retardancy. 

Poly(vinyl chloride) (PVC) has a high level of chlorine and as a result is considered inherently flame retardant. However, in many circumstances further improvement in flammability reduction of PVC is desired. An efficient way to enhance flame retardation of PVC is by the addition of Sb202 as a synergist. Additive retardants based on halogen and/or phosphorus are also employed. 

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