Gas Transport and Separation Properties of Polynorbornene Treated with Elemental Fluorine in a Perfluorodecalin Liquid

Белов, Н. А.; Nikiforov, R. Yu.; Alentiev, A. Yu.; Bezgin, D. A.; Blinov, I. A.; Суворов, А. В.; Kostina, J.V.; Legkov, S. A.; Левин, И. С.; Gringolts, M. L.; Shapagin, A. V.; Алиев, А. Д.

doi:10.1134/s2517751621060020

Cited by 4 publications

(6 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…%, and the C/O ratio reached 2.7-3.8, i.e., the amounts of oxygen and fluorine atoms in the repeat unit of the polymer were comparable. Significant oxidation was previously observed for liquid-phase treatment of poly(2,6-dimethylphenyleneoxide-1,4) [23] and metathesis-based polynorbornene [24] with the elemental fluorine.…”

Section: Xps Analysis Of the Pvtms Samplesmentioning

confidence: 79%

Surface and Structural Characterization of PVTMS Films Treated by Elemental Fluorine in Liquid Perfluorodecalin

et al. 2023

View full text Add to dashboard Cite

Poly(vinyl trimethylsilane) (PVTMS) films were subjected to direct surface fluorination in liquid medium (perfluorodecalin). The samples were investigated using several techniques: SEM-XEDS, XPS, ATR-IR, and contact angle measurement. The methods used allowed us to estimate chemical changes occurring because of the treatment. ATR-IR showed that most of the changes occurred in the Si(CH3)3 group. Monofluorinated Si(CH3)3 groups formed in the near-surface layer (Ge crystal, 0.66 µm penetration) after 30 min of fluorination, and then di- and trifluorinated groups appeared. Oxidation of the film with oxygen was also shown with the use of ZnSe crystal (2 µm penetration). The XPS method allowed an assessment of the ratio of the main elements at the surface of the fluorinated film. Two different exponential models were proposed to fit the experimental data of SEM-XEDS. Based on the model with the intercept, the depth of fluorination was estimated to be ≤1.1 µm, which is consistent with the result from the literature for the gas-phase fluorination. Contact angle measurements showed that oxidation of the PVTMS surface prevailed for the first 45 min of fluorination (surface hydrophilization) with a subsequent fluorine content increase and hydrophobization of the surface upon 60 min of fluorination.

show abstract

Section: Xps Analysis Of the Pvtms Samplesmentioning

confidence: 79%

Surface and Structural Characterization of PVTMS Films Treated by Elemental Fluorine in Liquid Perfluorodecalin

et al. 2023

View full text Add to dashboard Cite

show abstract

“…The fluorination time ( t F ) dependence of the change in the content of fluorine atoms C(F) over the thickness L of the PIM-1 films is presented in Figure 9 a. It was pointed out previously that in the case of low and middle permeable polymers (cellulose acetate [ 9 ], polynorbornene [ 8 ], polystyrene [ 11 , 31 ], etc. ), a sharp boundary between the fluorinated layer and bulk polymer was detected by IR-spectroscopy [ 32 ], SEM and XEDS [ 8 , 9 ] techniques.…”

Section: Resultsmentioning

confidence: 99%

“…It was pointed out previously that in the case of low and middle permeable polymers (cellulose acetate [ 9 ], polynorbornene [ 8 ], polystyrene [ 11 , 31 ], etc. ), a sharp boundary between the fluorinated layer and bulk polymer was detected by IR-spectroscopy [ 32 ], SEM and XEDS [ 8 , 9 ] techniques. The fluorine concentration profiles ( Figure 9 a) show that C(F) is maximal on the surface of the films and gradually decreases as the depth increases.…”

Section: Resultsmentioning

confidence: 99%

“…Here, the almost inert liquid phase (a perfluorinated organic liquid) withdraws the reaction heat and should potentially allow the reaction to be performed under mild conditions. This method has been tested previously on conventional polymers (polyphenyleneoxide [ 5 ], substituted celluloses [ 6 ], polystyrene [ 7 ] and polynorbornene [ 8 ]). It was demonstrated that the temperature and fluorine concentration in the fluorinated mixture with helium did not significantly affect the consumption of fluorine, and resulted in surface layers with low fluorine content.…”

Section: Introductionmentioning

confidence: 99%

“…It was demonstrated that the temperature and fluorine concentration in the fluorinated mixture with helium did not significantly affect the consumption of fluorine, and resulted in surface layers with low fluorine content. This might be partially associated with low mobility of the fluorine in the treated polymeric materials, since the polymers belong to a group of materials with average and low permeability (oxygen permeability coefficient varies in the range of 0.6–24 Barrer [ 8 , 9 , 10 , 11 ]). The depth of fluorination has been shown to strongly depend on the diffusion coefficient of fluorine in the polymer precursor [ 3 , 12 ].…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Hydrophobic–Hydrophilic Properties and Characterization of PIM-1 Films Treated by Elemental Fluorine in Liquid Perfluorodecalin

et al. 2022

View full text Add to dashboard Cite

A direct fluorination technique was applied for the surface treatment of PIM-1 films in a liquid phase (perfluorodecalin). The fluorinated samples were analyzed by various instrumental techniques. ATR-IR spectroscopy showed that the fluorination predominantly takes place in methylene- and methyl-groups. Cyano-groups, aromatic hydrogens and the aromatic structure of the PIM-1 repeat unit were shown to be relatively stable at the fluorination conditions. XPS confirmed that the concentration of fluorine, as well as oxygen, in the near surface layer (~1 nm) increases with fluorination time. C1s and O1s surface spectra of the fluorinated PIM-1 samples indicated an appearance of newly-formed C-F and C-O functional groups. Scanning electron microscopy and X-ray energy-dispersive spectroscopy of the fluorinated PIM-1 samples showed an increase of the fluorine concentration at the surface (~0.1–1 μm) with the treatment duration. Analysis of the slices of the PIM-1 films demonstrated a decline of the fluorine content within several microns of the film depth. The decline increased with the fluorination time. A model of fluorine concentration dependence on the film depth and treatment duration was suggested. A change in the specific free surface energy as a result of PIM-1 fluorination was revealed. The fluorination time was shown to affect the surface energy (γSV), providing its shift from a low value (25 mJ∙m−2), corresponding to tetrafluoroethylene, up to a relatively high value, corresponding to a hydrophilic surface.

show abstract

Gas separation properties of PIM-1 films treated by elemental fluorine in liquid perfluorodecalin

Белов

Alentiev

Nikiforov

et al. 2023

Polymer

View full text Add to dashboard Cite

Gas Transport and Separation Properties of Polynorbornene Treated with Elemental Fluorine in a Perfluorodecalin Liquid

Cited by 4 publications

References 35 publications

Surface and Structural Characterization of PVTMS Films Treated by Elemental Fluorine in Liquid Perfluorodecalin

Surface and Structural Characterization of PVTMS Films Treated by Elemental Fluorine in Liquid Perfluorodecalin

Hydrophobic–Hydrophilic Properties and Characterization of PIM-1 Films Treated by Elemental Fluorine in Liquid Perfluorodecalin

Gas separation properties of PIM-1 films treated by elemental fluorine in liquid perfluorodecalin

Contact Info

Product

Resources

About