13 research outputs found
Stress relaxation of bi-disperse polystyrene melts:Exploring the interactions between long and short chains in non-linear rheology
Entangled Polymer Melts in Extensional Flow - Characterization by Combined Rheology and Small-Angle Neutron Scattering
Structural studies of three-arm star block copolymers exposed to extreme stretch suggests persistent polymer tube
Relaxation Mechanism and Molecular Structure Study of Polymer Blends by Rheological and SANS experiments:87th Annual Meeting of The Society of Rheology, October 11-15, 2015
Synthesis of fluorinated poly(arylene ether)s with dibenzodioxin and spirobisindane units from new bis(pentafluorophenyl)- and bis(nonafluorobiphenyl)-containing monomers
New series of 4,4′-bis(pentafluorophenyl)- and 4,4′-bis(nonafluorophenyl)-containing monomers based on hexafluorobenzene or decafluorobiphenyl as well as on para- and meta-connecting dihydroxyl-substituted compounds or tetrafluorobenzene- and 1,1,1,3,3,3-hexafluoropropane-based dihydroxyl-substituted compounds were synthesised. Fluorinated poly(arylene ether)s having perfluorinated aromatic units as well as both rigid dibenzodioxin and spirobisindane fragments were successfully obtained by interaction of the synthesized core-fluorinated monomers with 5,5′,6,6′-tetrahydroxy-3,3,3′,3′-tetramethyl-1,1′-spirobisindane. The chemical structures of the prepared monomers and polymers were determined using 1H, 13C, 19F NMR and FTIR spectroscopy techniques. All the obtained polymers were completely soluble in chloroform, tetrahydrofuran, dimethylformamide, and dimethyl sulfoxide. Polymers derived from 4,4′-bis(nonafluorophenyl)-containing monomers have higher average molecular masses (Mw) in the range 47,000–88,300 and are able to form robust, solvent-cast films. Good thermal stabilities in air (up to 350 °C) were observed in all fluorinated polymers. The Brunauer–Emmett–Teller specific surface area and the pore size of polymers can be controlled by varying the type of the initial fluorinated monomers. It was shown that introduction of perfluorobiphenyl units is an effective tool for increasing the surface area up to 156.8 m2 g−1
