Synthesis and Radical Polymerization of Perfluoro-2-methylene-1,3-dioxolanes

Abstract

A new efficient synthetic route was developed for perfluorinated 2-methylene-1,3-dioxolane monomers via a direct fluorination of the hydrocarbon precursors prepared from methyl pyruvate and diols. Perfluoro-2-methylene-4,5-dimethyl-1,3-dioxolane (PMDD) and perfluoro-3-methylene-2,4-dioxabicyclo-[4.3.0]nonane (PMDN) were thus synthesized via this new method, among which PMDN is first reported. The radical polymerizations of those monomers were performed under various conditions. The kinetic results indicated that polymerization rate of PMDD is higher than that of PMDN. Oxygen did not affect the polymerization yield but strongly affected the polymer structure. The polymerization in the presence of oxygen produced a polymer containing unstable units. Hydrogen-containing solvents result in a lower molecular weight polymer. 2,2′-Azobis(isobutyronitrile) cannot initiate the polymerization in a perfluoro solvent or in bulk. Also, photopolymerizations of those monomers were performed in the presence of carbon tetrabromide or carbon tetrachloride, and the mechanism is discussed. The polymer of PMDD has a glass transition temperature at 155°C, and the polymer of PMDN has a glass transition temperature at 161°C. These polymers with high glass transition temperature, low refractive index, low material dispersion, and extraordinary optical transmission from the deep ultraviolet to near-infrared regions may be used as optical fibers, pellicles, or antireflective coating materials.

Gas separation membranes prepared with copolymers of perfluoro(2-methylene-4,5-dimethyl-1,3-dioxlane) and chlorotrifluoroethylene

“…Hexafluorobenzene (HFB), perfluoro-2-butyltetra hydrofuran Fluorinert 1 FC-75 (FC-75), chlorotrifluoroethylene (CTFE) were purchased from SynQuest, Inc. PFMDD and perfluorobenzoyl peroxide (PFBP) were synthesized according to methods described in our previous papers [26,[30][31][32]. All other solvents were purchased from Sigma-Aldrich, Inc. and were used as received.…”

Theoretical prediction of structural, vibrational and NMR parameters of plastic optical fiber (POF) material precursors. Cis and trans perhydro- and perfluoro-2-methylene-4,5-dimethyl-1,3-dioxolanes

“…A c c e p t e d M a n u s c r i p t 3 On the other hand, theoretical prediction of structure and spectroscopic parameters has been frequently used to support experimental works [18][19][20][21][22][23][24]. Despite very accurate (benchmark) results obtained for small molecules with very sophisticated methods including electron correlation (e. g. coupled cluster with single, double and perturbative treatment of triples, CCSD(T) [25][26][27][28]) and very large and flexible one-electron basis sets [29][30][31][32] there are more affordable and robust methods producing fairly accurate results for larger size molecules [33].…”

“…With the recent advent of information transfer using waveguide techniques, the pursuit for novel POF materials [1][2][3][4][5] is among the forefront topics in material sciences. The properties of these polymer materials are critically dependent on the understanding and controlling monomer structure, properties and their purity [1,2,[6][7][8][9][10].…”

“…The properties of these polymer materials are critically dependent on the understanding and controlling monomer structure, properties and their purity [1,2,[6][7][8][9][10]. Polymer optical fiber (POF) is produced from monomers yielding amorphous material with relatively high glass transition temperature (T g ), low signal loss in the near infrared electromagnetic frequency region (NIR) and high bandwidth [3][4][5]11]. Such materials are obtained by polymerization of specific monomers containing in their structure fluorine instead of hydrogen, e. g. perfluorinated molecules.…”

“…The one-and two-dimensional multinuclear ( 1 H, 13 C and 19 F) NMR spectroscopy in solution and their numerous variants in the solid state are the methods of choice for characterization of such systems. There appeared several excellent experimental reports on synthesis and NMR characterization of PFMMD monomers and polymers by teams of Liu [3], Okamoto [3,9,10,17] and Rinaldi [1].…”