Microporous polymers from superacid catalyzed polymerizations of fluoroketones with p-quaterphenyl: Synthesis, characterization, and gas sorption properties. (12th October 2016)

• Record Type: Journal Article
• Authors: Olvera, Lilian I.; Ruiz-Treviño, F. Alberto; Balmaseda, Jorge; Ronova, Inga A.; Zolotukhin, Mikhail G.; Carreón-Castro, María P.; Lima, Enrique; Cárdenas, Jorge; Gaviño, Ruben
• Is Part Of: Polymer. Volume 102(2016)
• Page Start: 221
• Page End: 230
• Publication Date: 2016-10-12
• Subjects: p-Quaterphenyl -- Fluoroketones -- Superacid -- Gas adsorption -- Free volume -- Kuhn segment; Polymers -- Periodicals; Polymerization -- Periodicals; Polymères -- Périodiques; Polymérisation -- Périodiques; 547.7
• DOI: 10.1016/j.polymer.2016.09.021
• Languages: English
• ISSNs: 0032-3861

Abstract

Abstract: Novel fluorinated aromatic polymers were obtained by one-pot, metal-free, superacid-catalyzed step-polymerization of trifluoromethylalkyl1 (a -b ) and trifluoromethylaryl (1c) ketones with p -quaterphenyl (A ). The room temperature polymerizations performed in a mixture of trifluoromethanesulfonic acid (CF3 SO3 H, TFSA) with methylene chloride gave polymeric particles. Thermogravimetric analysis for the particles revealed insignificant weight loss below 500 °C confirming their polymeric nature. Studies of solid state NMR revealed the incorporation of p -quaterphenyl in the polymer chain. The regioselectivity of polymerizations involving p -quaterphenyl and fluoroketones has been confirmed by the preparation and NMR characterization of soluble copolymers of trifluoroacetophenone (1c ) with p -terphenyl/quaterphenyl mixtures. Conformational rigidity and free volume calculations confirm polymers with medium hardness and with free volumes around 0.205–0.221 cm 3 /g. Scanning electron microscopy show rough surfaces with pore sizes around 20–50 nm. The H2, N2 and CO2 adsorption isotherms show that these polymers may possess intrinsic microporosity making them potential molecular sieves. Graphical abstract: Highlights: Fluoropolymers were synthesized by metal-free superacid-catalyzed step-polymerization. For the first time, p -quaterphenyl was used in Friedel-Crafts syntheses of homopolymers. Fluoropolymers possess good chemical and thermal stability. Scanning electron microscopy show rough surfaces with pore sizes around 20–50 nm. The H2, N2 and CO2 adsorption isotherms show intrinsic microporosity in the polymers.