Improved thermal stability of perfluoropolyalkylethers (PFPAEs)

Howell, Jon L.; Friesen, Chadron M.; Shtarov, Alexander B.; Thrasher, Joseph S.; Waterfeld, Alfred; Pérez, Erik W.; Sullivan, Jonathan F.

doi:10.1002/jsl.42

Cited by 10 publications

(6 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…6a, b ), and the maximum degradation rate is around 200 °C. It was demonstrated that a facile and severe thermal degradation of PFPAE components can occur in the presence of Lewis acid (such as AlF 3 ) [ 60 ] or even in presence of Al 2 O 3 [ 61 ]: in these conditions, a complete degradation of fluorinated chains occurs above 180 °C [ 60 , 61 ]. In our case, as the cationic polymerization requires the formation of superacids [ 1 ] that can still be present in the photocured networks, the thermal stability of the PFPAE-based copolymers has been adversely affected.…”

Section: Resultsmentioning

confidence: 99%

Vinyl ethers and epoxides photoinduced copolymerization with perfluoropolyalkylether monomers

et al. 2020

Self Cite

View full text Add to dashboard Cite

New perfluoropolyalkylether (PFPAE) monomers, chain extended with different alkyl groups and functionalized with vinyl ether or epoxide end-groups, were employed, together with trimethylolpropane trivinyl ether or trimethylolpropane triglycidyl ether, to produce fluorinated copolymers. The photoinduced cationic polymerization was investigated, and the PFPAE-based copolymer properties were thoroughly characterized. Interesting surface properties and two different values of refractive index were observed: thus, these fluorinated copolymers can be suitable materials for the manufacture of self-cleaning coatings and optical waveguides.

show abstract

Section: Resultsmentioning

confidence: 99%

Vinyl ethers and epoxides photoinduced copolymerization with perfluoropolyalkylether monomers

et al. 2020

Self Cite

View full text Add to dashboard Cite

show abstract

“…Although the mechanism of CF 3 COF release during the first stage of decomposition is still not clear, , it is generally believed that the oxide surface is slowly fluorinated by a nucleophilic substituted CF 3 COF followed by a second stage where the rapid decomposition of PFPE commences via a chain reaction catalyzed by freshly formed strong Lewis acid (FeF 3 ) sites, resulting in complete fluorination and decomposition of PFPE fluids into volatile perfluorocarbons, carbonyl fluoride, oxidized products, and hydrogen fluoride if any water is present. Much of the documented literature reports − that the majority of the second-stage byproducts are (CF 3 ) 2 CO and low molecular weight Krytox chains but other degradation mechanisms cannot be completely dismissed.…”

Section: Results and Discussionmentioning

confidence: 99%

“…Although the mechanism of CF 3 COF release during the first stage of decomposition is still not clear, 54,55 it is generally believed that the oxide surface is slowly fluorinated by a nucleophilic substituted To obtain mechanistic insights into the metal fluoride formation, all the volatile chemical species generated during heat treatment were analyzed using mass spectrometry (MS). The presence of COF is due to ionization of COF 2 produced by oxidation of trifluoroacetyl fluoride and hexafluoroacetone, whereas CF 3 is from ionization of C 2 F 6 released by thermal decomposition of hexafluoroacetone or trifluoroacetyl fluoride.…”

Section: Acs Applied Energy Materialsmentioning

confidence: 99%

Lithium Insertion Mechanism in Iron Fluoride Nanoparticles Prepared by Catalytic Decomposition of Fluoropolymer

Vijayakumar

Cho

Govind

et al. 2019

ACS Appl. Energy Mater.

View full text Add to dashboard Cite

Metal fluorides with high redox potential and capacity from strong metal–fluoride bond and conversion reaction make them promising cathodic materials. However, detailed lithium insertion and extraction mechanisms have not yet been clearly understood and explained. Here we report low-temperature synthesis of electrochemically active FeF3/FeF2 nanoparticles by catalytic decomposition of a fluoropolymer [perfluoropolyether (PFPE)] using a hydrated iron oxalate precursor both in air and in inert atmosphere. Freshly synthesized FeF3 nanoparticle delivered specific capacity above 210 mAh/g with decent cycling performance as a Li-ion battery cathode. Both in situ and ex situ characterization techniques were used to investigate the detailed PFPE decomposition and fluorination mechanisms leading to FeF3/FeF2 formation as well as the lithium insertion mechanism in a FeF3 cathode. Specifically, a detailed understanding was investigated using thermogravimetry–mass spectroscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, nuclear magnetic resonance, transmission electron microscopy, scanning electron microscopy/energy dispersive spectroscopy, and X-ray absorption near-edge structure. The novel synthesis route developed not only offers access to electrochemically active metal fluorides but also offers a catalytic approach for decomposing highly inert fluoropolymers for environmental protection.

show abstract

“…3a, b). The PFPAE thermal degradation may be triggered by the presence of Lewis acids such as AlF 3 [77] or Al 2 O 3 [78] and can result in a complete loss of the fluorinated segments above 180°C. Moreover, the thermal behavior could be adversely affected by residues of the superacids generated during the photoinitiation of the cationic polymerization and still present in the network.…”

Section: Photopolymers Characterizationmentioning

confidence: 99%

Novel perfluoropolyalkylethers monomers: synthesis and photo-induced cationic polymerization

et al. 2021

Self Cite

View full text Add to dashboard Cite

Several difunctional oligomers were synthesized by functionalizing perfluoropolyalkylether (PFPAE) chains with different vinyl ethers and epoxides end-groups. Due to their innate synthetic challenges and demanding purification protocols, the PFPAE derivatives were obtained in low yield and with an average functionality lower than 2. However, the functionalized PFPAE oligomers were successful in being used in photo-induced cationic polymerization processes, obtaining transparent and soft films. The influences of the fluorinated chains, and various end-groups on the photopolymerization process were investigated, as well their chemical stability, thermal degradation, and surface properties. Graphical abstract

show abstract

Improved thermal stability of perfluoropolyalkylethers (PFPAEs)

Abstract: End-group modifi cation of poly(hexafl uoropropylene oxide

Cited by 10 publications

References 12 publications

Vinyl ethers and epoxides photoinduced copolymerization with perfluoropolyalkylether monomers

Vinyl ethers and epoxides photoinduced copolymerization with perfluoropolyalkylether monomers

Lithium Insertion Mechanism in Iron Fluoride Nanoparticles Prepared by Catalytic Decomposition of Fluoropolymer

Novel perfluoropolyalkylethers monomers: synthesis and photo-induced cationic polymerization

Contact Info

Product

Resources

About