Thermal degradation product

Flammability information Flash point Fire point Flammable limits (LEL, UEL) Ignition temperature Spontaneous heating Toxic thermal degradation products Vapour pressure Dielectric constant Electrical resistivity Electrical group Explosion properties of dust in a fire... 

Industrial painters may suffer adverse health effects from over exposure to paint by skin contact or accidental ingestion, from excessive inhalation of paint aerosol, solvent vapour, or of dust in the case of electrostatically-applied powder coatings (e.g. polyesters containing triglycidyl isocyanurate), or from exposure to thermal degradation products from heated paint or plastic coatings (Table 5.48). 

Consideration of the potential toxicity of the agent, any thermal degradation products, or products generated on contact with chemicals present will dictate safety measures. 

The mass spectrum of polymeric sulfur S, prepared from either liquid sulfur or by extraction of commercial flowers of sulfur , has been measured and interpreted in terms of Ss, Sy, and Ss molecules leaving the polymer on heating and depolymerization [203]. This result is in agreement with depolymerization studies in solution which also show Ss and Sy as the major thermal degradation products [174]. 

Ignition temperature Spontaneous heating Toxic thermal degradation products... 

Scotter, M.J., Castle, L., and Appleton, G.P., Kinetics and yields for the formation of colonred and aromatic thermal degradation products of annatto in foods, Food Chem., 74, 365, 2001. 

Scotter, M.J., Characterization of the coloured thermal degradation products of bixin from annatto and a revised mechanism for their formation, Food Chem., 53, 111, 1995. Zechmeister, L., Cis-trans isomerization and stereochemistry of carotenoids and diphenylpolyenes, Chem. Rev., 34, 267, 1944. 

Similarly, toluene suspensions of the polystyrene housing of TV sets were examined by means of TPPy-FTMS (300-1200 K) [224], Diphenylether (DPE) was evidenced by peaks at m/z 141, 142 and 170 and decabromobiphenyl (DBBP) by m/z 943 and 864. Decabromodiphenyl ether (DBDPE) was recognised by thermal degradation products around m/z 800... 

Contaminants in recycled plastic packaging waste (HDPE, PP) were identified by MAE followed by GC-MS analysis [290]. Fragrance and flavour constituents from first usage were detected. Recycled material also contained aliphatic hydrocarbons, branched alkanes and alkenes, which are also found in virgin resins at similar concentration levels. Moreover, aromatic hydrocarbons, probably derived from additives, were found. Postconsumer PET was also analysed by Soxhlet extraction and GC-MS most of the extracted compounds (30) were thermally degraded products of additives and polymers, whereas only a few derived from the original contents... 

Karlsson D, Spanne M, Dalenea M, Skarping G (2000) Airborne thermal degradation products of polyurethane coatings in car repair shops. J Environ Monit 2 462 169... 

Mass spectrometry (MS) coupled with pyrolysis has been a key technique in detecting the thermal degradation products of polymers, and thereby elucidating their thermal decomposition pathways [69]. In pyrolysis-MS, a sample is thermally decomposed in a reproducible manner by a pyrolysis source that is interfaced with a mass spectrometer. The volatile products formed can then be analysed either as a mixture by MS or after separation by GC/MS [70]. 

Holloman, M.E., B.R. Layton, M.V. Kennedy, and C.R. Swanson. 1975. Identification of the major thermal degradation products of the insecticide mirex. Jour. Agric. Food Chem. 23 1011-1012. 

Enthalpy barriers for the decarbonylation and dethiocarboxylation of y-thiobutyrolactone (364) have been calculated as 378 and 404 kJ moP respectively, which accords with the experimental results which saw CO as the major and COS as the minor thermal degradation products.Phenyl and 4-nitrophenyl chlorothionoformates (365 X = H, NO2) reacted with phenolates in aqueous dioxane with /3 uc = 0.55 and 0.47, respectively, from which it was concluded that a concerted mechanism prevailed. 

Gomez,]., Bruneau, C., Soyer, N., andBrault, A. Identification of thermal degradation products from diuron and iprodione,/ Agrlc. Food Chem., 30(1) 180-182, 1982. 

Peltonen K, et ah Determination of the presence of Bisphenol A and the absence of diglycidyl ether of Bisphenol A in the thermal degradation products of epoxy power paint. Am Ind Hyg Assoc J 47 399, 1986... 

Christos T, Forshey DR. 1981. Thermal degradation products of solvents and hydraulic fluids used in mining. Report to U.S. Department of the Interior, Bureau of Mines, Washington, DC, by Bureau of Mines, Pittsburgh Research Center, Pittsburgh, PA. NTIS No. PB81-197154. 

Cook, W.A. (1980) Industrial hygiene evaluation of thermal degradation products from PVC film in meat-wrapping operations. Am. ind. Hyg. Assoc. J., 41, 508-512... 

It should not be thought, however, that perfluorocarbons are completely inert toward combustion. Even the very inert perfluorocarbon polymer polytetrafluoroethylene [PTFE, Du Pont s Teflon F(CF2CF2)nF] is thermodynamically unstable in oxygen with respect to CO2 and CF4 (Exercise 12.6) and can burn in a 95% 02/5% N2 mixture at 0.1 MPa, although combustion is hard to initiate because of the nonvolatility of PTFE and the resistance of the thermal degradation products to oxidation. Conflagrations involving more reactive, volatile fluorocarbons such as perfluoro-toluene have been reported.15... 

Parsons et al(Ref 83a) applied gas chromatography to separation of MNT and DNT isomers from their mixts. Ettre Varadi(Ref 85) used it in analysis of thermal degradation products of polymers, such as NC. Kuwada (Ref 89) detd w in hydrazine and de la Porte Lightenberg (Ref 100) detd triacetin in NG propint. Wilhite(Ref 100a) designed a gas chromatograph intended to be soft-landed on the surface of the moon as part of the "Surveyor spacecraft. It is assumed that the gas chromatograph would conduct, while on the lunar surface, an analysis of volatile constituents found on the moon... 

Flash vacuum pyrolysis of cocaine 1 at 550°C results in complete conversion to thermal degradation products. The major products isolated were benzoic acid (100%), N-methylpyrrole (74%) and methyl 3-butenoate (60%). 

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