Halogenated FR additives

Use of higher-performance polymers may suppress the demand for FRs in business machines. Flame retardancy has recently been reviewed [39], as well as the technology of halogen-free FR additives [44]. The future technology of polymer flame retardancy has been described [45]. 

For a given level of fuel at a given thickness with the same halogen content, most halogenated compounds show more or less the same flame retardancy. The key differences among these FR additives are effects on flow, melt stability, mechanical properties and long-term ageing of the FR-PBT blend. Different end-use requirements may call for the addition of different FR additives. 

PT are also active in lubricating oils and vinylic monomers. Multicomponent mixtures comprising HAS 28 (R = H), PT 20 and DPA 9a or a phenolic AO were proposed as antiwear additives for lubricating oils. PNA or dinaphthyl-PD provide excellent thermostability and suppress discoloration of PUR or PE doped with halogenated FR. Any negative influence of potentially released hydrogen halogenides from FR on amines was observed in these combinations. 

Reduction of HAS activity in applications in flame and weather resistant polymers and coatings containing halogenated FR is solved by means of HAS having reduced basicity (Sect. 3.3.2). The danger of antagonism in blends HAS/FR is reduced by addition of hydrotalcite [270]. terf-HAS 34 may be used for stabilization of PVC in combination with the conventional HS (salts of carboxylic acids, organotin compounds) [271]. 

Fiame retardants 5 Greater use of FR PCs, restrictions on halogen-based FRs Nonhalogen FRs synergies from combined FR additives... 

Another fundamental interaction issue is halogenated FRs negative effert on UV stability. This especially affects POs formulated for outdoor use, which rely on light-stabilizing (HALS) additives for long-term UV resistance. Here, a nonhalogenated FR is the obvious solution, or, if possible a more innovative approach described in Case 5. 1. 

The use of fire retardant (FR) additives, and/or halogenated FR resins in gelcoats detracts from their weatherabiUty and for external applications it is good practice to achieve fire retardancy by using a highly FR laminating resin behind a non-FR gelcoat. 

It was thought earlier that the non-interactive nature of NOR HALS with the halogens present in FR additives positively influenced the performance. It was found that NORs alone provide flame retardancy in their own right. 

Flame retardant companies have featured strongly in recent merger and acquisition activity. Manufacturers of halogenated FRs have been diversifying by buying smaller companies that produce other types of flame retardant, mainly phosphorus types and metal hydroxides. Great Lakes acquired the process additives division of FMC, which inclnded phosphorus FRs, and seemed some business components for use in its own water treatment business at the same time. The French part of Ferro was bought by Albemarle, which now makes PyroChek FRs. Albemarle pmchased Martinswerk, makers of ATH. 

FR additives may be inorganics, such as aluminium trihydrate (ATH), antimony oxide, or zinc borate, or organics such as phosphate esters or halogenated compounds of various types. 

Most FR additives contain bromine, chlorine, phosphorus, antimony, or aluminium. Among the main types are brominated hydrocarbons additive and reactive phosphate esters non-halogenated and halogenated antimony oxide trioxide and pentoxide, and sodium derivatives chlorinated hydrocarbons chlorinated paraffins, chlorinated cycloaliphatics. Other types include chlorinated/ brominated compounds, fluorinated compounds, magnesium carbonate, magnesium hydroxide, melamine, molybdenum compounds, silicone polymer. 

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