Synthesis of methallylic monomers bearing ammonium side‐groups and their radical copolymerization with chlorotrifluoroethylene

Abstract

Methallylic monomers bearing triethyl or 4-diazabicyclo[2.2.2]octane (DABCO) ammonium side-groups are prepared and copolymerized with chlorotrifluoroethylene (CTFE). First, three different monomers are synthesized from chloro-2-methylprop-1-ene or 3-chloro-2-chloromethylprop-1-ene in fair to good yields (57-95%). Then, several parameters (initiators, aqueous or solution processes, temperature) of the radical copolymerization of these monomers with chlorotrifluoroethylene are investigated. Various initiators are tested in the presence of ammonium perfluorooctanoate (APFO) as watersoluble surfactant, and tert-butyl peroxypivalate/APFO leads to the best results in a mixed solvent (H 2 O/CH 3 CN/C 4 F 5 H 5 ). In all experiments, the radical copolymerization shows that CTFE is more reactive than the methallylic monomer as evidenced by the characterization of poly(CTFE-co-M) copolymer by nuclear magnetic resonance spectroscopy and elemental analysis. Thermal degradation of these copolymers by thermogravimetric analyses indicates that the copolymers are stable up to 180 C without any degradation and have a T d,10% above 300 C. Finally, their ionic exchange capacities range between 0.94 and 1.69 meq g 21 .

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

“…The peak at ca. À80 ppm is assigned to the two À ÀCF 3 groups located on the 4 and 5 position of the dioxolane ring of PFMDD unit; a group of broad and overlapped peaks from À100 to À130 ppm are attributed to the À ÀCF 2 À À and À ÀCClFÀ À units [22][23][24] on the polymer backbone as well as the two À ÀCFÀ À groups of the dioxolane ring. By using the integrals of the À ÀCF 3 peak and the region of À100 to À130 ppm from both the spectra of poly(PFMDD-co-CTFE) copolymer and the PFMDD homopolymer, the fraction of CTFE in the copolymers can be estimated.…”

Grafting Polytetrafluoroethylene Micropowder via in Situ Electron Beam Irradiation-Induced Polymerization

“…Because of the high electro-negativity and large atomic radius compared to hydrogen atoms, fluorine atoms in fluoropolymers exhibit a strong intramolecular repulsion force and thus arrange spirally along the carbon backbone as a protective sheath [ 20 ]. Moreover, high bond energy and low polarizability of C–F bonds give rise to weak intermolecular actions with fluoropolymer themselves or other materials [ 21 ]. As expected, the fully fluorinated polymer, i.e., polytetrafluoroethylene (PTFE), shows an extremely low surface energy (γ s = 2.02 × 10 −2 N/m) [ 22 ].…”

Plant-Based Nonactivated Olefins: A New Class of Renewable Monomers for Controlled Radical Polymerization

“… a (a) Synthesis of acrylate monomers from renewable resources and their radical polymerization, − (b) polymerization of allylic monomers using free radical polymerization (FRP) in the presence of Lewis acids, − and (c) the synthesis of renewable allylic monomers and their controlled copolymerization with vinyl acetate using cobalt-mediated radical polymerization (CMRP). …”

“…Since alcohol functional groups are very abundant in natural molecules (e.g., glycerol and glucose as prominent examples), a large number of novel allylic molecules can be synthesized sustainably and are then available for radical polymerizations as will be demonstrated herein. However, up to now only a few examples of free radical polymerizations of such allylic monomers exist (Scheme b), − as the direct polymerization of such nonactivated double bonds is still very challenging to achieve. This difficulty has been known since the 1940s and is a result of degradative chain transfer from the polymer to the monomer during the polymerization: A stabilized allyl radical with an extremely low propagation rate is formed, which limits the polymerization to low conversions. ,− Equally, olefinic double bonds of fatty acids have so far not been incorporated into polymers using radical polymerizations for similar reasons.…”