Reordering of polystyrene gel due to multiple swelling in organic vapor fast transient fluorescence technique study
Yükleniyor...
Dosyalar
Tarih
2006-07-31
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Elsevier Science SA
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
Reordering of disc-shaped polystyrene (PS) gels due to multiple swelling, under organic vapor was studied by using Fast Transient Fluorescence (FTRF) technique. Disc-sbaped polystyrene gels were prepared by free radical copolymerization (FRC) of styrene (S) with ethylene glycol dimethacrylate (EGDM) as a crosslinker. Pyrene (P) was introduced as a fluorescence probe during polymerization. Swelling experiments were performed by using P doped PS gels under chloroform vapor. After each swelling step, gels were left to dry in an oven at 30 degrees C for consecutive reswelling experiments. Decay curves of P were measured and pyrene lifetimes, tau, were determined. It was observed that tau values decreased as swelling recycles were repeated. It was observed that after the fifth swelling step, two different regimes appeared in the swelling processes in PS gels. Swelling time constant, tau(c), and cooperative diffusion coefficients, D-c were determined by using Li-Tanaka equation for each swelling step in both regimes. It was observed that D-c values decreased up to tenth swelling step and then remained unchanged in both regimes.
Açıklama
Anahtar Kelimeler
Diffusion, Fast transient fluorescence, Gel, Hydrogels, Kinetics, Light, Phase transition, Polyacrylates, Reordering, Swelling
Kaynak
Journal Of Photochemistry And Photobiology A-Chemistry
WoS Q Değeri
Q2
Scopus Q Değeri
Q2
Cilt
181
Sayı
2-3
Künye
Erdoǧan, M. & Pekcan, M. Ö. (2006). Reordering of polystyrene gel due to multiple swelling in organic vapor. fast transient fluorescence technique study. Journal of Photochemistry and Photobiology A: Chemistry, 181(2-3), 394-400. doi:10.1016/j.jphotochem.2005.12.025
