Correlation between the onset of beadless character of nanofibrous webs and rheological characteristics of electrospun polymer solutions

0547480 - ÚH 2023 RIV CZ eng C - Konferenční příspěvek (zahraniční konf.)
Zelenková, Jana - Peer, Petra - Filip, Petr
Correlation between the onset of beadless character of nanofibrous webs and rheological characteristics of electrospun polymer solutions.
NANOCON 2021 - Conference proceedings. Ostrava: Tanger Ltd., 2021, s. 454-459. ISBN 978-80-88365-00-6. ISSN 2694-930X.
[International Conference on Nanomaterials - Research & Application /13./ NANOCON. Brno (CZ), 20.10.2021-22.10.2021]
Grant CEP: GA MŠMT(CZ) LTC19034
Institucionální podpora: RVO:67985874
Klíčová slova: nanofibres * beadless morphology * PVDF-co-HFP * polymer concentration * rheology
Obor OECD: Textiles
https://www.confer.cz/nanocon/2021/4375-correlation-between-the-onset-of-beadless-character-of-nanofibrous-webs-and-rheological-characteristics-of-electrospun-solutions

An overwhelming majority of applications of nanofibrous webs requires sufficiently smooth character of nanofibres surface. This character is apart other parameters strongly influenced by a concentration of chosen polymeric material in the solvents. Qualitative attributes roughly depend on the prepared concentration, specifically whether it belongs to one of the four basic regions: dilute, semidilute unentangled, semidilute entangled and concentrated. A concentration separating the latter two regions is often taken as a zero-th approximation indicating an onset of beadless nanofibrous webs. The present contribution uses as a more precise indicator behaviour of so-called phase angle relating viscous and elastic moduli, in other words mutual participation of viscous and elastic components. To this aim three frequently used polymers were used: copolymer of poly(vinylidene fluoride) and hexafluoropropylene (PVDF-co-HFP), poly(ethylene oxide) (PEO) and poly(vinyl butyral) (PVB). For materials exhibiting first a constant behaviour or moderate decrease in a phase angle for lower concentrations, an approximation of the starting concentration is given by a concentration value where a phase angle curve starts to decrease, apparently reflecting a more progressive viscoelastic nature. As shown, such approximation provides relatively very good approximation enabling to eliminate a traditional trial-and-error method.
Trvalý link: http://hdl.handle.net/11104/0324185