Synthesis of Fluorine-Containing Polymers by Functionalization of cis-1,4-Polyisoprene with Hypervalent Iodine Compounds

Abstract

Hypervalent (HV) iodine­(III) compounds with fluorine-containing ligands (F, CF3, C6F5CO2, or CF3(CF2)8CO2 (n-C9F19CO2)) reacted, in the presence of iodine or copper salts, with the double bonds in cis-1,4-polyisoprene (polyIP) to afford fluorine-containing polymers. For instance, fast iodo-fluorination of polyIP was accomplished in the presence of 4-(difluoroiodo)­toluene (4-TolIF2) and iodine. The reaction of polyIP with 1-trifluoromethyl-1,2-benziodoxol-3­(1H)-one (Togni reagent II) and copper­(I) iodide under mild conditions yielded polymers with vicinal pendant trifluoromethyl and 2-iodobenzoate groups, which were subjected to acid-promoted elimination to give a fluorine-containing unsaturated polymer. The simultaneous introduction of trifluoromethyl groups and a halogen (Cl or Br) was achieved by reacting polyIP with Togni reagent II in the presence of thionyl halide and copper­(II) salts. The alkyl chloride pendant groups in the product of the copper-mediated reaction of polyIP with thionyl chloride and Togni reagent II were subsequently converted to azide functionalities by nucleophilic substitution with NaN3, and the produced azide-containing polymer was subjected to copper­(I)-catalyzed “click” coupling reaction with a fluorescent alkyne, propargyl 4-(1-pyrenyl)­butyrate. Perfluoroacyloxy pendant groups were also introduced successfully by the reaction of polyIP with HV iodine­(III) reagents with perfluorinated carboxylate ligands, i.e., C6H5I­(O2CC6F5)2 and C6H5I­(O2C­(n-)­C9F19)2, in the presence of iodine. No significant chain degradation and/or cross-linking was observed in any of the functionalization reactions. The modified polymers showed relatively good thermal stability and high hydrophobicity, with contact angles toward water in the range of 89–116°.

Electrochemical deposition of highly hydrophobic perfluorinated polyaniline film for biosensor applications

“…To the best of our knowledge, this is the highest value to date for a water-repelling conductive polymer. We must say that another uorinecontaining polymer was investigated and its water contact angle was 116 , as reported by Tsarevsky et al 24 A high water contact angle for a non-uorinated polymer was measured by E. Lindner et al for a hydrophobic derivative of poly (3,4ethylenedioxythiophene), and it was 136 AE 5 . 6 The static water contact angle measurements reveal that by changing the deposition duration we can tune the water contact angle of the peruorinated lms from 120 to 140 .…”

Diatomite‐filled epoxy resin composites: Curing behavior, dielectric, and thermal properties

“…[24][25][26][27] On the other hand, much attention has been given to the introduction of C F bonds by many researchers due to the low polarizability and increased free volume. 20,[28][29][30][31] Cheng et al 19 reported that epoxy reinforced with tetrafluorophenyl (FEP) displayed excellent thermal stability, and improved dielectric properties. In summary, fluoropolymers are widely used in cutting-edge fields because of their outstanding thermal properties, dielectric properties, and chemical resistance.…”

Upcycling of Polybutadiene Facilitated by Selenium‐Mediated Allylic Amination

“…An alternative approach to modify polydienes utilizes olefin transposition reactions to retain backbone unsaturation. [37] For example, treatment with triazolinediones [33,[38][39][40] or hypervalent iodine compounds [41] affords functionalized polydienes, albeit with concomitant alkene migration. Because microstructure in unsaturated polymers can influence physical properties, [42][43][44] it would be advantageous to retain the original 1,4-diene microstructure following upcycling.…”