Pyrolysis of Fluorocarbons<sup>1</sup>

Steunenberg, R.K.; Cady, George H.

doi:10.1021/ja01136a062

Cited by 30 publications

(20 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Swar ts [1 ),2 Rogers and Cady [2], and Steunenb erg and Cady [3) pyrolyzed a number of low molecular weigh t fluorocarbons in t be presence of a glowing platinum filamen t. Lewis and Naylor [4l pyrolyzed polytetrafluoroethylene at 600 0 and 700 0 C and at press ures vary ing from 5 to 760 mm. Hg.…”

Section: Introductionmentioning

confidence: 99%

Thermal degradation of tetrafluoroethylene and hydrofluoroethylene polymers in a vacuum

Madorsky¹,

Hart²,

Straus³

et al. 1953

J. RES. NATL. BUR. STAN.

126

View full text Add to dashboard Cite

T e fl on and tetrafluoroethyle ne photopolymers, on py rolysis in a vacuum at 423.5 0 to 513.0 0 C, yield almost J 00 per ce nt of monom er. The r ate of formation of monome r at a n.,· given tem p e rat ure fo llows a first-order react ion and is independe nt of t he method of pre pa ration of poly mer or its initial ave rage molecu lar weight. The activation energy was determined by a press ure method and a wei gh t met hod , and a value of 80.5 k cal was found b.'· both methods . A prelimina ry heating of Teflo n in air a t 400 0 to 470 0 C did not change a ppreciably its rate of degradation into mono me r when it was s ubseque ntl y heated in a yacuum . Polyvinyl fluorid e, 1,I -polyv in y li dene fluorid e, and polytrifluo roethylene were pyr olyzed in t he range 372 0 to 500 0 C. The volatiles consisted in all cases of HF and a wax-lik e mate rial co nsisting of chain fragments of low volatili ty. P olyvinyl fluoride and polyt rifl uoroet hyle ne deg rade to co mplete volatilization, whereas 1,1-poly viny li dene fluoride becomes stabilized at about 70-pe rcent loss of we ig ht. The rate-of-volat ilization curves indicate a fi l'st-o rder reaction for poly vinyl fluo ri de, a zero-order reaction fo r t riflu oroethy le ne, alld an undeterm in ed ord er for 1,1-polyvinyli dene fluoride. The orde r of t hermal s tabili ty for t hese poly me rs, as com pared with polymet hy lene, is as follows: Poly vin yl f1uoride < poly me th,vle ne < polyt riflu oroethylene < ] . J -polyvi nylidene f1uor idc < polytetrafluoroeth ylene.

show abstract

Section: Introductionmentioning

confidence: 99%

Thermal degradation of tetrafluoroethylene and hydrofluoroethylene polymers in a vacuum

Madorsky¹,

Hart²,

Straus³

et al. 1953

J. RES. NATL. BUR. STAN.

126

View full text Add to dashboard Cite

show abstract

“…CF 2 O then reacts readily with water to produce CO 2 and HF, (Croce & Castellano, 1989) resulting in the measured TFA-F recovery of 83% (Figure 4). However, CF 2 = CF 2 produced from PFPrA may form more stable olefins and perfluoroalkanes, which may partially explain the lower F recovery from PFPrA (ARITO & SODA, 1977;Batey & Trenwith, 1961;Steunenberg & Cady, 1952). The data suggest that recovery of PFCAs and PFSAs by CIC-F TOC has similar performance to commercial CIC instruments operating at 900-1100 C, with 60%-85% recovery of PFOA-F (Schultes et al, 2019;von Abercron et al, 2019).…”

Section: Pfas Structurementioning

confidence: 90%

Quantification of per‐ and polyfluoroalkyl substances with a modified total organic carbon analyzer and ion chromatography

et al. 2021

View full text Add to dashboard Cite

Quantification of per-and polyfluoroalkyl substances (PFAS) via mass spectrometry is highly sensitive but targets a limited number of compounds and the instrumentation is not available in many laboratories. We developed a methodology to determine total organofluorine by modifying a total organic carbon analyzer, which is common in laboratories across disciplines. Evolved hydrogen fluoride was captured in an impinger and analyzed by ion chromatography. Recovery of fluorine from 20 PFAS was dependent on terminal functional group and alkyl chain length. The method detection limit based on perfluorooctanoic acid (PFOA) spiked samples was 36 μg-F/L (52 μg PFOA/L). Fluorine recoveries of spiked PFAS in river water and wastewater were similar to those spiked in deionized water. The recovery of inorganic fluorine present in sodium fluoride was 91%. Therefore, researchers should be cautious when applying methods that pre-combust samples to differentiate organoand inorganic fluorine, because the combustion process may cause inadvertent losses of inorganic fluorine, resulting in an overestimation of organofluorine.

show abstract

“…Since the synthesis of a truly high polymer is often more difficult than smaller molecules, some studies have been made on smaller molecules to ascertain the appropriate approach to a high- temperature polymer. Early work on small fluorocarbon molecule studies is mainly that of Cady [ 1 ]. He carried out gas-phase pyrolysis of hexafluoroethane, decafluorocyclopentane, octafluoropropane, decafluoro- n -butane, and dodecafluoro- n -pentanes.…”

Section: Discussionmentioning

confidence: 99%

“…Knowledge of the thermal decomposition mechanisms of fluorocarbon materials and the influence of molecular structure on their thermal stability is fairly limited. There is ample evidence that linear perfluoroaliphatic substances have a high thermal stability [ 1 , 2 ] 1 but few if any results are available for branched and aromatic perfluorocompounds or for the various copolymers containing fluorine, which are becoming important commercially. The mechanism of depolymerization or decomposition of these materials, with the possible exception of polytetrafluoroethylene [ 3 to 7 ], is also in need of extensive investigation, since such information would be useful in understanding the problems involved in the development of thermally more stable materials.…”

Section: Introductionmentioning

confidence: 99%

Pyrolysis of fluorocarbon polymers

Wall¹,

Straus²

1961

J. RES. NATL. BUR. STAN. SECT. A.

View full text Add to dashboard Cite

Th e t herm al deco mposition of variou s flu oro carbon p olymers were inv est iga,ted ; volatile p rodu cts of t he d ecomposition were d et ermined along with t he overall rates of volatili zation, a nd from t h ese rates t he acti vation energies were calculated for t he thermal deg radation r eactions. The t hermalJ y m ost stable of all t he poly mers t hus far st ud ied a re t he co mpletely flu orin ated o nes. H owever, e vid ence from a s t udy of t he dccomposition of h exafluorop ropy lene t elomers and from th e study of a copolym cr of t etra flu oroe thylene and hexafl uo ropropylene suggest s t hat the homopolymer of hexaflu o roprop ylene, if it co uld be m ad e, wou ld be quite unstable. The photoindu ced d ecomposi tion of polyt rifiu orochloroet hylene was also investigated , a nd estimates of t he activa tion energies wer e ob tain ed for the variou s elementar y step s of t he deco mposi tion m echanism:] Th e photoindu ced exp er imc nts indica ted that mu t ual termination of t he radical i nt erm ediates takes place and t hat a diff usion effect on d ep ropagation b cco mes pronoun ced below 250°C.

show abstract

Pyrolysis of Fluorocarbons¹

Cited by 30 publications

References 0 publications

Thermal degradation of tetrafluoroethylene and hydrofluoroethylene polymers in a vacuum

Thermal degradation of tetrafluoroethylene and hydrofluoroethylene polymers in a vacuum

Quantification of per‐ and polyfluoroalkyl substances with a modified total organic carbon analyzer and ion chromatography

Pyrolysis of fluorocarbon polymers

Contact Info

Product

Resources

About

Pyrolysis of Fluorocarbons1

Cited by 30 publications

References 0 publications

Thermal degradation of tetrafluoroethylene and hydrofluoroethylene polymers in a vacuum

Thermal degradation of tetrafluoroethylene and hydrofluoroethylene polymers in a vacuum

Quantification of per‐ and polyfluoroalkyl substances with a modified total organic carbon analyzer and ion chromatography

Pyrolysis of fluorocarbon polymers

Contact Info

Product

Resources

About

Pyrolysis of Fluorocarbons¹