Fluorinated polymers: evaluation and characterization of structure and composition

Abstract

The proposed review represents the systematic analysis of modern methods and approaches for the characterization and structural evaluation of fluorinated polymers that have found a wide application as materials for chemical processing, chemically resistant components and coatings, pharmaceutical and electrical packaging, biomedical equipment, etc. The chemical composition of the polymers (fluorine content, its distribution inside the fluorinated materials, chemical bonds, presence of oxygen-containing groups) substantially influences on the operation properties (chemical resistance, adhesive, cohesive, optical, dielectrical, thermal, barrier, gas permeation) of the final polymeric products. Hence, it was of particularly importanсe to bond the emergence of specific features with the presence of fluorine in the chemical structure of polymer by means of related analytical techniques. Namely, we focused on spectral (IR, UV-VIS, NMR, XPS, EPR), chemical (elemental analysis), Secondary-ion mass spectroscopic (SIMS) and microscopic (AFM, SEM-EDX) methods emphasizing their general consideration and limitations as well as application for the in-depth characterization.

Photo- and Electroluminescent Neutral Iridium(III) Complexes Bearing Imidoylamidinate Ligands

“…CHNS elemental analyses for Ir3 , Ir4 , and Rh1 were performed using a Eurovector EA3000 analyzer. The analyses of Ir2 are not possible with the conventional equipment because this complex contains fluorine atoms . In view of these difficulties, we proceeded via the usual organic chemistry approach and characterized Ir2 by NMR spectroscopy and high-resolution electrospray ionization mass spectrometry; these methods fully confirmed the structure and composition of the obtained compounds.…”

Bis(perfluoroaryl)chalcolanes ArF2Ch (Ch = S, Se, Te) as σ/π-Hole Donors for Supramolecular Applications Based on Noncovalent Bonding

“…It is commonly known that F-containing organic compounds give low-molecular weight F-containing species (including HF) that spoil the equipment. It is, in particular, following from ref ., where stated that “a standard CHNSO method of high-temperature combustion of sample in a stream of pure oxygen suffers from underestimation of C content due to the formation of thermostable low molecular fluorinated compounds in the combustion region.” In view of all these technical difficulties and also considering that the obtained compounds are metal-free organic species, we proceeded via the standard organic chemistry methodology and characterized novel compounds by NMR spectroscopy ( 13 C­{ 19 F} and 19 F­{ 1 H}) and gas chromatography–mass spectrometry; these methods fully confirmed the structure and composition of the obtained compounds.…”