Browsing by Subject "Polyacrylamide"
Now showing items 1-6 of 6
-
Effect of LCST on the swelling of PAAm-NIPA copolymers: a fluorescence study
Authors:
Publisher and Date:(Springer, 2012)Temperature sensitive copolymers were prepared by free radical crosslinking copolymerization in aqueous solution with different molar percentage of N-isopropylacrylamide (NIPA) and acrylamide (AAm) monomers. NN'-methylenebis (acrylamide) (BIS) and ammonium persulfate (APS) were used as a crosslinker and an initiator respectively. The steady-state fluorescence (SSF) technique was used to determine the low critical phase transition temperature (LCST) for PAAm-NIPA copolymers. Swelling experiments ...
-
Effect of multiwalled carbon nanotube (MWNT) on the behavior of swelling of polyacrylamide-MWNT composites
Authors:
Publisher and Date:(Sage Publications Ltd, 2014)The purpose of this paper is to discuss the role of multiwalled carbon nanotube in the swelling of polyacrylamide-multiwalled carbon nanotube composites. Swelling experiments were performed in water at various temperatures by real-time monitoring of the decrease in pyranine (Py) and emission light intensity (I-em). The Stern-Volmer equation is modified for low-quenching efficiencies to interpret the behavior of pyranine intensity during the swelling of polyacrylamide-multiwalled carbon nanotube ...
-
Effect of temperature and graphene oxide on the swelling of PAAm-GO composite gels
Authors:
Publisher and Date:(Avestia Publishing, 2019)Graphene oxide (GO) is a two dimensional carbon material with similar one-atom thickness, and is a light material having extremely high strength and thermal stability [1]. Thus, GO is an efficient filler for the enhancement of the electrical, mechanical and thermal properties of composite materials [2]. We focused on GO as a nanofiller in polyacrylamide hydrogels and PAAm-GO composites to investigate the effect of temperature and graphene oxide on the swelling. Polyacrylamide (PAAm) hydrogels have ...
-
Swelling Kinetics of PAAm-kappa-Carrageenan Composites: A Fluorescence Technique
Authors:
Publisher and Date:(Taylor & Francis Inc, 2011)The steady-state fluorescence (SSF) technique was introduced for studying swelling of disc-shaped polyacrylamide (PAAm) gels containing various amount of kappa-carrageenan (kappa C). They were prepared by free-radical cross-linking copolymerization. N N'-methylenebisacrylamide (BIS) and ammonium persulfate (APS) were added as a crosslinker and an initiator respectively. Composite gels were prepared at 80 degrees C with pyranine as a fluorescence probe. After drying of these gels swelling kinetics ...
-
Temperature effect on the swelling of PAAm-kappa-carrageenan composites
Authors:
Publisher and Date:(Wiley-Blackwell, 2012)The steady-state fluorescence (SSF) technique was used for studying swelling of disc-shaped polyacrylamide (PAAm)-kappa-carrageenan (kappa C) composites which were prepared by free-radical crosslinking copolymerization at 80 degrees C. Pyranine was introduced as a fluorescence probe during polymerization. Swelling experiments were performed in water at various temperatures by real-time monitoring of the pyranine (Py) fluorescence intensity I which decreased as swelling proceeded. Stern-Volmer ...
-
The Role of Pyranine in Characterization of PAAm-kappa C Composites by Using Fluorescence Technique
Authors:
Publisher and Date:(Springer/Plenum Publishers, 2011)Polyacrylamide (PAAm) doped by kappa-carrageenan (kappa C) gels were prepared with various amounts of kappa C varying in the range between 0 wt.% and 3 wt.%. Steady-state fluorescence (SSF) technique was employed for studying sol-gel transition and swelling of PAAm-kappa C composite gels which were prepared by free-radical crosslinking copolymerization. Pyranine was introduced as a fluorescence probe. Pyranine molecules start to bind to acrylamide polymer chains upon the initiation of the ...