Akademik Veri Yönetim Sistemi
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING, cilt.114, sa.3, ss.951-956, 2014 (SCI-Expanded)
Steady-state fluorescence (SSF) technique was employed for studying swelling of polyacrylamide (PAAm) gels with various content of kappa-carrageenan (kappa C). Disc shaped composite hydrogels were prepared by free-radical crosslinking copolymerization of acrylamide (AAm) with various amounts kappa C. N,N'-methylenebis (acrylamide) (BIS) and ammonium persulfate (APS) were used as crosslinker and initiator, respectively. Pyranine was introduced as a fluorescence probe. Fluorescence intensity of pyranine was monitored during in situ swelling processes of composite gels. It was observed that fluorescence intensity values decreased as swelling is proceeded. Li-Tanaka equation was used to determine the swelling time constants, tau and cooperative diffusion coefficients, D from intensity variations during the swelling processes. It was shown that swelling time constants, tau decreased and diffusion coefficients, D increased as the kappa C content in the composites are increased.