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Polytetrafluoroethylene decomposition

Polytetrafluoroethylene decomposition products thermal decomposition of the fluorocarbon chain in air leads to the formation of oxidized products containing carbon, fluorine and oxygen. Because these products decompose in part by hydrolysis in alkaline solution, they can be quantitatively determined in air as fluoride to provide an index of exposure. No TLV is recommended pending determination of the toxicity of the products, but air concentration should be minimal. (Trade names Algoflon, Fluon, Teflon, Tetran.)... [Pg.176]

Plaster of Paris Platinum, soluble salts (as Pt) Polychlorobiphenyls, see Chlorodiphenyls Polytetrafluoroethylene decomposition products Propane... [Pg.382]

Polytetrafluoroethylene decomposition products Overexposures result in polymer fume fever, a disease with fiu-iike symptoms inciuding chills, fever, and cough. See also p 259. Produced by pyrolysis of Teflon and related materials. Perlsofluorobutylene and carbonyl fluoride are among the pyrolysis products. [Pg.607]

Eig. 6. Decomposition of polymers as a function of temperature during heating. A, polymethylene B, polytetrafluoroethylene C, silicone D, phenoHc resin ... [Pg.6]

The ignition temperature of a mixture of Ti and C is relatively high compared with those of other pyrolants. When a small amount of polytetrafluoroethylene (Tf) is added to a Ti-C pyrolant, the ignition temperature is significantly lowered due to the exothermic reaction between Ti and Tf Since Tf consists of a -C2F4- chemical structure, the oxidizer gas, F2, is formed by thermal decomposition of Tf according to ... [Pg.321]

Polyvinyl fluoride and PVDF are more stable to elevated temperatures than the corresponding chloride polymers. The decomposition temperatures of polytrifluoroethylene and polytetrafluoroethylene (ptfe) are progressively higher than polymers of vinyl fluoride or vinylidene fluoride. The pyrolysis of PAN and polymethacrylonitrile yields polycyclic ladder polymers. [Pg.91]

The high-molecular-weight perfluoropolyethers obtained in the first step have excellent thermal stability (TGA initial decomposition >370°C) and chemical resistance and are true fluorocarbon elastomers that are, in contrast to polytetrafluoroethylene, flexible. Other methods for the synthesis of perfluoropolyethers and functionalized perfluoropolyethers are under development in our laboratories. [Pg.186]

The vacuum pyrolysis of thin samples of polytetrafluoroethylene follows first-order kinetics with monomer as the major decomposition product in the temperature range from 360—510° C (Siegle, Muus, and Lin). The rate constant does not depend on either the molecular weight or the type of polymer and is characterized by an activation enthalpy of 83.0 kcal/mole and a frequency factor of 3 x 1019 sec-1. The melt viscosity decreases during pyrolysis. [Pg.488]

Wall, L. A., and J. D. Michaelsen Thermal decomposition of polytetrafluoroethylene in various gaseous atmospheres. J. Research Natl. Bur. Standards 56. 27—34 (1956). [Pg.495]

Polymer fume fever An illness characterized by temporary flu-like symptoms caused by inhaling the products released during the decomposition of fluoropolymers, mainly polytetrafluoroethylene (PTFE). Tobacco smoke enhances the severity of this condition. [Pg.202]

The thermal decomposition of polytetrafluoroethylene has been studied by a number of workers Above 360 °C the main decomposition product is perfluoroethylene suggesting that CF2 or C2F4 units are cracked off the polymer. The decomposition follows simple first-order kinetics with an activation energy - ° of about 80 kcal.mole. ... [Pg.152]

The thermal stability of polytetrafluoroethylene oxide and PTFE have been compared under the same conditions by Donato et al. [263] between 450 and 600°C. The decomposition rate has a maximum at 628°C for the oxide and at 568°C for PTFE. The activation energy for the first-order degradations are 98 kcal mole"1 between 8.5 and 85% for the oxide polymer and 85 kcal mole-1 between 523 and 571°C for PTFE. The rate of weight loss is less than 1.2% per min for both polymers below T = 550°C for the oxide and T = 590°C for PTFE. The oxide, however, loses weight below 390° C whereas PTFE does not. The main components of the volatile material are trifluoroacetyl fluoride, carbonyl fluoride and tetrafluoroethylene. An end-initiated thermal degradation with small zip length is proposed. [Pg.125]

Polytetrafluoroethylene resins are very stable at their normal use temperature range (<260°C). They exhibit a small degree of degradation at higher temperatures. The rate of decomposition is a function of the specific polymer, temperature, time at temperature, and, to some extent, on the pressure and nature of decomposition environment. In actual processing, degradation is tracked by indirect measurement of mo-... [Pg.47]


See other pages where Polytetrafluoroethylene decomposition is mentioned: [Pg.168]    [Pg.186]    [Pg.1]    [Pg.593]    [Pg.97]    [Pg.85]    [Pg.168]    [Pg.186]    [Pg.1]    [Pg.593]    [Pg.97]    [Pg.85]    [Pg.4]    [Pg.273]    [Pg.12]    [Pg.281]    [Pg.639]    [Pg.455]    [Pg.120]    [Pg.281]    [Pg.12]    [Pg.560]    [Pg.518]    [Pg.655]    [Pg.150]    [Pg.158]    [Pg.754]    [Pg.4]   


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