Phthalic anhydride tetrabromo

FG 400 FG 4000 FireMaster PHT 4 Great Lakes PHT4 HSDB 5438 NSC 4874 PHT 4 Phthalio acid, tetrabromo-, anhydride Phthalic anhydride, tetrabromo- Saytex RB 49 Tetrabromo-phthalio acid anhydride Tetrabromophthalic anhydride ... 

The pyrolysis of a number of compounds at temperatures around 600— 800° and at pressures of the order of 10 2 mm. has been shown to give rise to benzyne. These compounds include for example indanetrione 29>, and phthalic anhydride 30 38>. The dimerisation of benzyne to yield biphenylene has been used preparatively 31 33>, an(j the pyrolysis of tetrafluorophthalic anhydride 34>, and tetrachlorophthalic anhydride 3i-33) gave the corresponding octahalobiphenylenes. In the case of the pyrolysis of tetrachlorophthalic anhydride some hexachlorobenzene is also formed, while the pyrolysis of tetrabromophthalic anhydride results in the formation of hexabromobenzene but no octabromobiphenylene. The disproportionation of tetrabromobenzyne to form carbon and bromine is a function of the high temperature involved and, as we shall see later, both tetrabromo- and tetraiodo-benzyne behave normally in solution. 

Polyethylene and a peroxide initiator were added to the usual BPA/DC-BMI-epoxide resin composition. The use of unsaturated polyesters from tetrabromo-phthalic anhydride, maleic anhydride and ethylene glycol as well as of other fire retardants was also described [99]. 

Phthalic anhydride has exclusively electron-withdrawing substituents and can be converted to the tetrabromo derivative in dilute sulfuric acid using an iron(II) iodide catalyst.454... 

A number of derivatives of fluorescein are useful dyes. Uranin is the disodium salt of fluorescein. ChrysoUn is a salt of benzyl-fluorescein, which is formed from phthalic anhydride and benzyl-resorcinol. It dyes silk and wool a fast yellow, and is used in cotton dyeing. Eosin is the disodium salt of tetrabromo-fluorescein, which is prepared by the action of bromine on fluorescein. Its dilute alkaline solution is rose-colored, and exhibits an intense yellow-green fluorescence. Other dyes related to fluorescein are tetrabromo-dichlorofluorescein and various ethers of fluorescein and its substitution-products. The dyes of this class produce on silk and wool shades from yellow to reddish yellow, cherry-red, and purple. 

Intrinsically non-flammable polymers are few, but phenolic resins have a good reputation both in Are and smoke performance, which has resulted in their becoming increasingly favoured for reinforced plastics structures, for example, underground transport, where such concerns are greatest. Polyether ether ketone (PEEK) is also a low fire and smoke polymer. Unsaturated polyesters, vinyl esters and epoxy resins bum readily, but modified versions are available with improved behaviour. For example, both bromine and chlorine are used extensively in the form of chlorendic (HET) acid, tetrachlorophthalic anhydride (TCPA) and tetrabromo-phthalic anhydride (TBPA) which can be reacted into the polyester in small quantities and can act as permanent (non-migrating) flame retardants. 

Phthalic acid, tetrabromo-, disodium salt. See Disodium tetrabromophthalate Phthalic acid, tetrachloro-. See Tetrachlorophthalic acid Phthalic anhydride... 

Cross-linked epoxy resins are combustible and their burning is self-supporting. They require mainly reactive flame-retardants, such as tetrachloro- or tetrabromobisphenol-A and various halogenated epoxides. Even the cross-linking agent may be flame-retardant, as in the case of chlorendic anhydride, tetrabromo- or tetrachloro-phthalic anhydride, or possibly phosphorus compounds. Halogenated agents can be supplemented with antimony trioxide. 

Chemical Name Tetrabromo phthalic anhydride Form White powder % Br 69... 

Tetrabromobisphenol A Chlorendic anhydride Tetrabromo phthalic anhydride... 

Tetrabromobisphenol A, 73, 77, 83 Tetrabromophthalic acid, 81 Tetrabromo phthalic anhydride, 77... 

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