Aliphatic flame retardants

Approximately 10 million pounds of trichloroethylene are used aimually as a chain transfer agent in the production of polyvinyl chloride (McNeill 1979). Other chemical intermediate uses of trichloroethylene include production of pharmaceuticals, polychlorinated aliphatics, flame retardant chemicals, and insecticides (Mannsville 1992 Windholz 1983). Trichloroethylene is used as a refrigerant for low-temperature heat transfer (Cooper and Hickman 1982 lARC 1979 McNeill 1979) and in the aerospace industry for flushing liquid oxygen (Hawley 1981 Kuney 1986). 

Figure 10. Impact polystyrene (12% Aliphatic flame retardant, 4% antimony oxide). Color (Hunter L-b) as a function of Carbon Arc Fadeometer exposure for flame retardant impact polystyrene stabilized with 0.50% of...

Figure 1.1 compares the flame retardant efficiency of aliphatic brominated flame retardant and aromatic brominated flame retardant. Because the thermal decomposition of the aliphatic flame retardant starts at temperatures below the thermal decomposition of pol5T)ropylene, it shows very good performance in polypropylene. In contrast, because the aromatic brominated fire retardant is significantly more stable, optimum debromination is not achieved at the temperature of decomposition of polypropylene, and this flame retardant shows inferior performance. 

An electric conductive rubber base containing carbon black is laminated with an electric conductive cover layer of phosphoric acid ester plasticizer and other ionic surfactants to prepare antistatic mats, where the covers have colors other than black. It is also reported that alkyl acid phosphates act as color stabilizer for rubber. Small amounts of phosphate esters are helpful in restoring reclaimed rubber to a workable viscosity [284,290]. Esters of phosphoric acid are used in the production of UV-stable and flame-retarded alkylbenzenesulfonate copolymer compositions containing aliphatic resins and showing a high-impact strength... 

Aromatic and aliphatic bromine compounds play an important role as industrial products, e.g. special products are widely used as flame retardants for polymeric materials (ref. 1). Because there is an increasing interest and concern about the behaviour and fate of anthropogenic compounds in the environment (ref. 2), we have studied the physical behaviour and chemical reactivity of these products which are relevant to the environment. The main object is the study of their thermal behaviour during incineration, as well as photolytic reactions. Of prime concern is... 

BFRs are one of the last classes of halogenated compounds that are still being produced worldwide and used in high quantities in many applications. In order to meet fire safety regulations, flame retardants (FRs) are applied to combustible materials such as polymers, plastics, wood, paper, and textiles. Approximately 25% of all FRs contain bromine as the active ingredient. More than 80 different aliphatic, cyclo-aliphatic, aromatic, and polymeric compounds are used as BFRs. BFRs, such as polybrominated biphenyls (PBBs), polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD), and tetrabromobisphenol A (TBBPA), have been used in different consumer products in large quantities, and consequently they were detected in the environment, biota, and even in human samples [26, 27]. 

HBCD is a brominated aliphatic cyclic hydrocarbon used as a flame retardant in thermal insulation building materials, upholstery textiles, and electronics. In 2001, the world market demand for HBCD was 16,700 tons, from which 9,500 tons was sold in the EU. These figures make HBCD the second highest volume BFR used in Europe [29], HBCD may be used as an alternative for PBDEs in some applications. To date, there are no restrictions on the production or use of HBCD. As a result of their widespread use and their physical and chemical properties, HBCD are now ubiquitous contaminants in the environment and humans [30, 31]. 

Figure 2. Flame retardancy of PP (1) aromatic Br (2) aliphatic Br (3) aliphatic and (4) aromatic Br with Sb 03 as synergist. (Curves 1-4 reprinted with permission from ref. 12. Copyright 1977 John Wiley and Sons. Curve 5, this paper data from Table I.)...

Organic bromamines, 13 104-112 Organic bromine compounds, 4 340-362 aliphatic, 4 345-349 chemical reactions, 4 341—343 dyes and indicators, 4 361-362t, 362 flame retardants, 4 349, 354, 355—358t industrial chemical intermediates, 4 350—353t... 

Because of the presence of the chlorine atom In every repeating unit PVC does not bum as readily as hope. When used as a plasticizer, tricresyl phosphate also contributes to flame retardancy. In contrast, the organic ester plasticizers, such as DOP, contribute to the combustibility of plasticized PVC Tricresyl phosphate is more toxic than organic esters, and DOP is more toxic than aliphatic esters, such as dioctyl adipate. 

The water-soluble flume retardants are most easily applied by impregnal-ing the fabric wilh a water solution of a retardant, followed by drying. The water-soluble flame retardants used must widely for textiles are listed in Tahle 3. Less commonly used retardants include sulfamates of urea or other amides and amines aliphatic amine phosphates, such as triethanolamine phosphate, phosphamic acid tamido phosphoric acid. and its... 

Other reactive P-containing comonomers reported to improve flame retardance in PET include aliphatic and alicyclic (spiro) bisphosphonates34 such as Structure 5.12. 

Reactive strategies, that is, chemical modifications, appear not to have been explored to a large extent as a route to improved flame retardance in aliphatic polyamides, probably because the chemical... 

Normally polymer structures containing aliphatic backbones are low in smokegenerating character and are generally not self-extinguishing. Additives to such systems to achieve flame-retardancy often enhances smoke generation Polymers with aromatic side groups such as polystyrene have a considerable tendency to generate smoke. 

Aliphatic chlorine compounds find some utility as flame retardants for styrenic polymers, but aromatic chlorine compounds are probably too stable to be effective [21]. Aliphatic bromine compounds are too thermally unstable for com-... 

Because expanded polystyrene foam is processed at a lower temperature, aliphatic bromine compounds such as hexabromocyclododerane (HBCD) can be used for this application. The flame retardant levels in these systems are family low, typically less than 3wt%. These levels are sufficient to pass the Steiner Tunnel test, and synergists such as antimony trioxide are not necessary. 

A very different solution, and one suitable even for the selective production of HBr in the presence of chlorine, without any catalyst, is the treatment of the pyrolysis oils with molten polypropylene [13, 63, 56, 57, 59], Polypropylene acts within a temperature range of 310-350°C as a hydrogen donor. HBr is evolving from the brominated phenols and substituted phenols are formed in the case of the decomposition of flame retardants such as tetrabromobisphenol A (Figme 20.8). Together with HBr small brominated aliphatics are formed. Those can be converted to HBr together with all noncondensable compounds in a final oxidative cleaning. 

Chemical Description Aliphatic Aromatic Bromine Low viscosity, excellent non-scorching flame retardant for flexible foam. 

Chemical Description Aromatic Bromine Aliphatic Chlorine Lower smoke and lower cost than brominated flame retardants, used to flame retard polypropylene, polyethylene, SBR, unsaturated polyesters and fabrics. 

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