Replacement flame retardants

Since flame retardants have been recognized as not desirable (although not properly quantified in economic valuation), there is now work on replacing flame retardants with other additives with the same functionality. 

Assuming that equal mass of additives is needed, the CBA shows that it is good for society to replace flame retardants in furniture if ... 

Keywords Elame retardants PBDEs HBCDs TBBPA BERs Halogenated flame retardants Brominated flame retardants Replacement flame retardants House dust Polyurethane foam Eoam furniture Plastics used in TVs and computers Electronics Eood packaging Eood contact materials Children s products Carpets and textiles... 

PentaBDE and OctaBDE have not been produced in the U.S. since 2004, yet millions of pounds of these and other untested replacement flame retardants mixed with foam and plastic are present in household products and dust. The continued use of FRs with established health concerns and introduction of replacement FRs with limited toxicity data highlights the need to modernize U.S. chemical policies to require disclosure and safety testing of household product chemicals prior to sale. 

Ba(B02)2 H2O, used in flame retardant plastic formulations as a synergist for phosphoms or halogen compounds and as a partial or complete replacement for antimony oxide (see Flame RETARDANTS), is excellent as an afterglow suppressant. The low refractive index of results in greater... 

It has already been mentioned in Chapter 5 that plasticisers are often replaced in part by extenders, materials which in themselves are not plasticisers but which can be tolerated up to a given concentration in a polymer-plasticiser system. Refinery oils and chlorinated waxes are widely used in PVC for this purpose with the prime aim of reducing cost although the chlorinated waxes may also be of use as flame retardants (q.v.). 

The need to evaluate alternatives often arises once the decision to eliminate chemicals of concern is made. Sometimes a chemical of concern can be eliminated through product design such as through the use of a material that is inherently flame retardant or a fabric barrier without the need for added flame-retardant chemicals. But when the only currently feasible option appears to be a chemical substitution, then the alternatives must be evaluated and assessed to ensure that they are in fact greener than the chemical they are intended to replace. We provide as examples of implementing alternatives assessment, the Green Screen for Safer Chemicals and the DfE Flame Retardants in Printed Circuit Boards Partnership. 

As is seen, this example shows that flame retardants might be good for society (from a socio-economic perspective) even if they cause a number of adverse environmental and human health impacts as long as the value of the avoided mortality impacts is larger. Replacement of flame retardants should only be done (from an economic perspective) if the replacement cost is smaller than the avoided environmental and human health values. 

Hence, it is apparent that certain inorganic tin compounds are very effective flame retardants and smoke suppressants for halogenated polymer formulations. Since these additives are generally non-toxic, their potential use as partial or total replacements for existing commercial flame retardants, such as antimony trioxide, is thought to merit serious consideration. 

This article reports on two related pieces of news firstly that Albemarle Corp. of the USA has introduced a new reactive flame retardant, Saytex RX 8500 , as a replacement for pentabromodiphenyl ether (penta-BDE) in the production of flame-retardant PU foam. Secondly that Great Lakes Chemical Corp., the only manufacturer of penta-BDE, has announced plans to voluntarily phase out and cease production of this, and also octa-BDE, at the end of 2004. 

The replacement of established chemistries with newer ones is one of the classic drivers of change in the chemical industry. One of the current hotbeds of this kind of change is the replacement of brominated flame retardants in polymer formulations. The brominated flame retardants under the most scrutiny have been polybrominated diphenyl ethers, particularly penta- and octabromodiphenyl ether, which have been shown to be persistent in the environment and to bioaccumulate. Great Lakes Chemical is voluntarily phasing out penta- and octa-BDEs by the end of next year. The phaseout is made possible by the clean bill of health granted by EPA for Firemaster 550, a replacement for penta-BDE in flexible PU applications. BRG Townsend claims the phaseout of penta-BDE and octa-BDE is not as earth shattering as would be an exit from deca-BDE, a styrenics additive that is produced in the highest volume of the PBDEs. 

In view of the utility of the aromatic polyesters and the demonstrated effectiveness of the aromatic polyphosphonates as flame retardants, the combination of these two polymers was chosen for this study. In addition, this system provided a composition in which both copolymers and polymer blends could be prepared with identical chemical compositions. The polyesters were prepared from resorcinol with an 80/20 m/m ratio of iso-phthaloyl and terephaloyl chlorides while the polyphosphonates were resorcinol phenylphosphonate polymers. Copolymerized phosphorus was incorporated by replacement of a portion of the acid chloride mixture with phenylphosphonic dichloride. 

H M (Hennes Mauritz) uses no flame retardants in any product line, using instead natural materials that are inherently flame resistant. In a few cases, the company has cancelled clothing line items that proved a potential flammable hazard and could not be materially replaced. ... 

UBA remarked that It is encouraging that there is a general trend to refrain from the use of halogenated flame retardants in products and to replace them with less problematic flame retardants or to redesign flame retardant systems, e.g. by creating greater distances to potential heat sources. ... 

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