Browsing by Subject "Temperature"
Now showing items 1-5 of 5
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Critical phenomenon during photoinitiated gelation at different temperatures: A Photo-DSC study
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Publisher and Date:(Elsevier Science, 2011)The behaviour of photoinitiated radical polymerization of an 80 wt% epoxy diacrylate (EA) and 20 wt% tripropyleneglycoldiacrylate (TPGDA) mixture with 2-mercaptothioxanthone (TX-SH) photoinitiator was studied at different temperatures by using photo-differential scanning calorimetric (Photo-DSC) technique. All photopolymerization reactions were carried out under the same conditions. It was observed that all conversion curves during gelation at different temperatures present nice sigmoidal behaviour ...
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Drying of polyacrylamide-multiwalled carbon nanotube (MWNT) composites with various MWNTs contents: a fluorescence study
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Publisher and Date:(Walter De Gruyter Gmbh, 2013)We studied the drying of polyacrylamide (PAAm)-multiwalled carbon nanotube (MWNT) composites prepared by free radical crosslinking copolymerization in water with a steady state fluorescence technique. Composite gels were prepared at room temperature with pyranine (Py) doped as a fluorescence probe. Drying experiments were performed in air at various MWNT contents by real time monitoring of the Py fluorescence intensity (I) which increased as the drying proceeded. The Stern-Volmer equation combined ...
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Effect of temperature and graphene oxide on the swelling of PAAm-GO composite gels
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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 ...
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Investigation of Drying of Poly(N-isoproplacrylamide-co-acrylamide) by Fluorescence Technique
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Publisher and Date:(Wiley-Blackwell, 2013)The steady-state fluorescence technique was performed on drying of various molar percentages of poly(N-isopropylacrylamide-co- acrylamide) [poly(NIPA-co-AAc)] to elucidate the mechanism of temperature-induced phase separation and the effect of monomer content. Poly(NIPA-co-AAc) copolymers were prepared by free radical cross-linking copolymerization. The fluorescence intensity I of pyranine introduced as a probe increased as drying time was increased for all samples. The behavior of I was modeled ...
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Monitoring of dynamical processes in PAAm-MWNTs composites by fluorescence method
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Publisher and Date:(Taylor & Francis Ltd, 2012)Polyacrylamide (PAAm)-multi walled carbon nanotube (MWNT) composites were prepared by free radical cross-linking copolymerization in water. Ammonium persulfate and NN'-methylenebis (acrylamide) (BIS) were used as a free radical initiator and a crosslinker respectively. The drying and swelling processes of disc shaped PAAm-MWNT composites were monitored by the steady-state fluorescence technique at various temperatures. Disc shaped composite gels were prepared with pyranine (P) doped as a fluorescence ...
