Flame retardant plasticizer

TrioctylPhosphate. Trioctyl phosphate [1806-54-8/, C24H 04P, has been employed as a specialty flame-retardant plasticizer for vinyl compositions where low temperature flexibHity is critical, eg, in military tarpaulins. It can be included in blends along with general-purpose plasticizers (qv) such as phthalate esters to improve low temperature flexibHity. 

Environmental Considerations. The phosphate flame retardants, plasticizers, and functional fluids have come under intense environmental scmtiny. Results pubUshed to date on acute toxicity to aquatic algae, invertebrates, and fish indicate substantial differences between the various aryl phosphates (159—162). The EPA has summarized this data as well as the apparent need for additional testing (147). 

Trialkyl esters of phosphonic acid exist ia two structurally isomeric forms. The trialkylphosphites, P(OR)2, are isomers of the more stable phosphonates, 0=PR(0R)2, and the former may be rearranged to resemble the latter with catalytic quantities of alkylating agent. The dialkyl alkylphosphonates are used as flame retardants, plasticizers, and iatermediates. The MichaeUs-Arbusov reaction may be used for a variety of compound types, including mono- and diphosphites having aryl as weU as alkyl substituents (22). Triaryl phosphites do not readily undergo the MichaeUs-Arbusov reaction, although there are a few special cases. 

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... 

One of the most stringent and most widely accepted test is UL 94 that concerns electrical devices. This test, which involves burning a specimen, is the one used for most flame-retardant plastics. In this test the best rating is UL 94 V-0, which identifies a flame with a duration of 0 to 5 s, an afterglow of 0 to 25 s, and the presence of no flaming drips to ignite a sample of dry, absorbent cotton located below the specimen. Tlie ratings go from V-0, V-l, V-2, and V-5 to HB, based on specific specimen thicknesses. 

The major problem of most flame retarded plastics is a decrease in processing heat stability. A method recommended by several producers of plastics to solve this problem is to decrease process temperature (Table 3). 

Kurebayashi H, Tanaka A, Yamaha T. 1985. Metabolism and disposition of the flame retardant plasticizer, tri-p-cresyl phosphate, in the rat. Toxicol Appl Pharmacol 77 395-404. 

Kim Y-J, Osako M, Shin-ichi S (2006) Leaching characteristics of PBDEs from flame-retardant plastics. Chemosphere Elsevier 65 8... 

Currently available flame retardants must often be employed at concentrations at which they have adverse effects on the other properties of flame-retarded plastics or textiles. 

Polyblends of Flame Retardant with Non-flame-retardant Plastics... 

London, Interscience Communications Ltd., 2002, Paper 4, p.33-43, 24 cm, 012 FLAME-RETARDANT PLASTICS AND SUSTAINABLE PRODUCT SPECIFICATION O Neill T J Polymeron Network... 

On Table I is a list of the major end uses for the new chemicals submitted up through the end of 1981. Intermediates in the manufacture of other chemicals, polymers for a variety of end uses but mainly for paints and coatings, and additives such as flame retardants, plasticizers and antioxidants for plastics account for over half of all the uses of these new chemicals. These seven major categories in total represent slightly over three fourths of all projected uses. One would suspect that this pattern will change with market demand and competitive developments and a year from now we might see intense R D activity in some other specific market areas culminate in the introduction of a line of new chemical substances. 

Some manufacturers use internal metal shields to protect computer housings from internal sparks and heat, and can therefore use non-flame retarded plastics. 

Uses. Antiseptics disinfectants solvent insecticides resins flame-retardant plasticizers... 

Polychlorinated biphenyls (PCBs), known by their trade marks of Arochlor (Monsanto U.S.), Phenochlor (in France), and Clophen (in Germany) are chemically similar to the chlorinated insecticides. Although not used for this purpose, their existence and persistence in the environment is well established. They were used to make more flexible and flame retardant plastics and are still used as insulating fluids in electrical transformers since there is no substitute in this application. They have been made by Monsanto since 1930 and were first discovered as a pollutant in 1966. U.S. production peaked at 72 million lb in 1970 but in 1975 it was down to 40 million Ib/yr because in 1971 Monsanto voluntarily adopted the policy of selling PCBs only for electrical systems. At least 105 PCBs are present in the environment. 

Tris (2-ethyl hexyl) phosphate (TOP) Tricresyl phosphate (TCP) Tributyl phosphate Triethyl phosphate Flame retardant plasticizers for inhibition of DB rocket propellants... 

Over 40 organophosphorus compounds (Figure 14.11) used as pesticides, flame retardants, plasticizers, pesticides, and in other applications have been tested for carcinogenicity and mutagenicity. The SAR analysis of organophosphorus compounds has been published [41]. 

W.J. Hall and P.T. Williams, Removal of organobromine compounds from the pyrolysis oils of flame retarded plastics using zeolite catalysts, J. Anal. Appl. Pyrolysis, 81(2) 139-147, March 2008. 

PCBs are industrial compounds used as industrial, dielectric and heat transfer fluids, organic solvents, flame retardants, plasticizers, sealant and surface coatings. They may also be released to the atmosphere by waste incineration (Fig. 3). The worldwide production of this compound has been 1.3 million tonnes, of which 97% in the northern hemisphere [23]. The amount of chlorine atoms in the biphenyl mixtures is related to the duration and temperature of the chlorination process. The commercial mixtures were distributed under names such as Aroclor (Monsanto, USA) or Clophen (Bayer, EU). The chlorine atoms can substitute the para, meta and/or ortho positions of the biphenyls. There are 209 possible congeners. PCBs can be divided into nine isomeric groups and one decachlorobiphenyl, all with an empirical formula of C Hjo-uCln (n = 1-10) (Fig. 4). 

They were used to make more flexible and flame-retardant plastics and are still used as insulating fluids in electrical transformers since there is no substitute in the application. Their existence and persistence in the environment is well established, and they are classed as a pollutant. 

Phosphate esters (alkyl or aryl, or mixed) of phosphoric acid constitute an important family of organophosphorus flame retardants.25 Triethylphosphate, a colorless liquid boiling between 209°C and 218°C, and containing 17 wt % phosphorus, has been used commercially as an additive for polyester resins/laminates and in cellulosics. In polyester resins, it functions as a viscosity depressant as well as a flame retardant. Trioctylphosphate is employed as a speciality flame-retardant plasticizer for vinyl composites where low temperature flexibility is critical. It can be also included in blends, along with general purpose plasticizers, such as phthalate esters, to improve low temperature flexibility. 

The selective treatments of flame-retardant plastics are fulfilled when the WEEE plastics are treated (recovered, recycled, thermally disposed) together with other wastes, as is the case with energy recovery processes that are currently practiced in Europe.78 79 In this scenario, the joint recovery of plastics containing brominated flame-retardants with other materials complies with the purpose of the WEEE Directive without the removal requirement of Annex II. Recent technical studies and legal reviews demonstrate that WEEE plastics containing brominated flame-retardants are compatible with the EU WEEE Directive without separation and removal prior to the waste treatment. This has been confirmed by the 2006 EU Member States guidance on the separation requirements of the WEEE Directive.80... 

Schlummer, M., Maurer, A., et al (2006) Report recycling of flame-retarded plastics from waste electric and electronic equipment (WEEE). Waste Management and Research, 24(6) 573-583. 

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