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Study of temperature-induced phase separation in copolymer solutions
Šťastná, Julie ; Hanyková, Lenka (advisor)
Title: Study of temperature-induced phase separation in copolymer solutions Author: Julie Brüllová Department: Department of Macromolecular Physics Supervisor: RNDr.Lenka Hanyková, Dr. Supervisor's e-mail address: hanykova@kmf.troja.mff.cuni.cz Abstract: The temperature-induced phase transition of poly(acrylamide/N-isopropylmethacryl- amide) random copolymers in D2O solutions and in mixtures of D2O/ethanol and D2O/aceton is studied in this work. This phenomenon is on the molecular level analogous with a phase transition (collapse) in hydrogels. Nuclear magnetic resonance (NMR) spectroscopy was used for the study. Results showed that with increasing content of acrylamide in the copolymer the transition tempe- rature is shifted to higher values, the transition is more gradual and smaller fraction of copolymer is phase separated. The same behaviour was found for higher content of ethanol or acetone in the solvent. If this content and the content of acrylamide is very high, the phase transition in dependence on the composition of solvent appears. The relaxation experiments showed that after the phase separation a part of solvent molecules remains bound to globular structures and its mobility is rescticted. Keywords: temperature induced phase separation, poly(acrylamide/N-isopropylmethacrylamide) random...
Study of temperature-induced phase separation in copolymer solutions
Šťastná, Julie ; Hanyková, Lenka (advisor)
Tit lr: Study of tempera! urc-indneed phase M'paNil ion in cnpol VIIKT noli it ions. Author; .Intie IJriilliiva I Jepar! incut; Department of MiUTOinnleeulai1 |']IVM< .- Supervisor: KM )r.l,enka llauvkova. Dr. Hnpervisoi ' - e-mail address- hanykova" l-imf I loja.mil.cnni.r/ Absl ract: I'lif tcinpci.ii ui I'-indnrcd pi MM' 11 HUM! ion oi pi)ly(;KT\/ A -iiMipropvlnirt h.u-i \- nniiilc) r;nidnru n>|]o|vnici - in [>_>(> snlui ion^ and in mixl mv^ of Dj<) 'd h.iuul ;ind DjO 'acftnn i^ it tidiI'd in linn work. I In.-, plir-immciHMi i.-> on [ lie nmicciihn1 level ;ni;ilof.',nu^ w i t ii ;i phiisc transit ion (coll,-i|ivcl in hydi o;.',cls. Nuclear ina^iiciic rcsnn.imc [ N M I ' ) ->pret n>^e',ip\ v.'a- u-cd tm' the ~lnd>". liesull.h sho\ved thill w i t h nici'i'.i^i nj1, c< ml ent of acrylaiuide in t lie ci >poi\niei1 i he i ra nation r<iinpc- laMii'e i> shifted lo hijdici1 \".ihic-~. t h e 11 aiisit ii ni is iimcc 1^1 adiial ;nid sinallei1 fi'ai I inn of copulx'Uiei is pluihf se|>ai'a!ed. The same liehavionr \\-as fniind ior hiidn-i enntenl i if ct lianol or aeetnne in 1 he Mtlvent. If This emiteiit and t h e content ut" arrylaiuidi' is very ln,",li. the pliaM.' transition in dc pci i delice on the eompo-it ion of snh-cnl appejir- The relnxat ion cxpciinient- sh(J\\-cd ( ha! alter ihe |)hase -eparntion a p;nt...
Stimuli Responsive Multicomponent Polymer Systems
Šťastná, Julie ; Hanyková, Lenka (advisor) ; Dušková - Smrčková, Miroslava (referee) ; Labuta, Jan (referee)
Title: Stimuli Responsive Multicomponent Polymer Systems Author: Julie Šťastná Department: Charles University in Prague, Faculty of Mathematics and Physics, Department of Macromolecular Physics Supervisor: doc. RNDr. Lenka Hanyková, Dr., Charles University in Prague, Faculty of Mathematics and Physics, Department of Macromolecular Physics Abstract: Combination of 1 H NMR spectroscopy, differential scanning calorime- try (DSC), dynamic mechanical measurement, and optical microscopy was used to investigate temperature-induced phase transition of three types of systems: i) in D2O solutions of poly(N-isopropylmethacrylamide-co-acrylamide) (P(NIPMAm/- AAm)) random copolymers and in interpenetrating networks ii) poly(N-isopropyl- methacrylamide/poly(N-isopropylacrylamide) (PNIPMAm/PNIPAm), and iii) po- ly(vinylcaprolactam)/poly(N-isopropylacrylamide) (PVCL/PNIPAm). In all sys- tems influence of composition of the system on the phase transition was studied. For i) both the NMR and DSC data showed dependence on the acrylamide (AAm) content in the copolymer. NMR data was used to construct van't Hoff plots and changes of the enthalpy ∆H and entropy ∆S were studied. As it follows from comparison of ∆H values for NMR and DSC the size of the domains undergoing the transition as a whole decreases with increasing AAm...
Study of temperature-induced phase separation in copolymer solutions
Šťastná, Julie ; Hanyková, Lenka (advisor)
Title: Study of temperature-induced phase separation in copolymer solutions Author: Julie Brüllová Department: Department of Macromolecular Physics Supervisor: RNDr.Lenka Hanyková, Dr. Supervisor's e-mail address: hanykova@kmf.troja.mff.cuni.cz Abstract: The temperature-induced phase transition of poly(acrylamide/N-isopropylmethacryl- amide) random copolymers in D2O solutions and in mixtures of D2O/ethanol and D2O/aceton is studied in this work. This phenomenon is on the molecular level analogous with a phase transition (collapse) in hydrogels. Nuclear magnetic resonance (NMR) spectroscopy was used for the study. Results showed that with increasing content of acrylamide in the copolymer the transition tempe- rature is shifted to higher values, the transition is more gradual and smaller fraction of copolymer is phase separated. The same behaviour was found for higher content of ethanol or acetone in the solvent. If this content and the content of acrylamide is very high, the phase transition in dependence on the composition of solvent appears. The relaxation experiments showed that after the phase separation a part of solvent molecules remains bound to globular structures and its mobility is rescticted. Keywords: temperature induced phase separation, poly(acrylamide/N-isopropylmethacrylamide) random...
Study of temperature-induced phase separation in copolymer solutions
Šťastná, Julie ; Hanyková, Lenka (advisor)
Tit lr: Study of tempera! urc-indneed phase M'paNil ion in cnpol VIIKT noli it ions. Author; .Intie IJriilliiva I Jepar! incut; Department of MiUTOinnleeulai1 |']IVM< .- Supervisor: KM )r.l,enka llauvkova. Dr. Hnpervisoi ' - e-mail address- hanykova" l-imf I loja.mil.cnni.r/ Absl ract: I'lif tcinpci.ii ui I'-indnrcd pi MM' 11 HUM! ion oi pi)ly(;KT\/ A -iiMipropvlnirt h.u-i \- nniiilc) r;nidnru n>|]o|vnici - in [>_>(> snlui ion^ and in mixl mv^ of Dj<) 'd h.iuul ;ind DjO 'acftnn i^ it tidiI'd in linn work. I In.-, plir-immciHMi i.-> on [ lie nmicciihn1 level ;ni;ilof.',nu^ w i t ii ;i phiisc transit ion (coll,-i|ivcl in hydi o;.',cls. Nuclear ina^iiciic rcsnn.imc [ N M I ' ) ->pret n>^e',ip\ v.'a- u-cd tm' the ~lnd>". liesull.h sho\ved thill w i t h nici'i'.i^i nj1, c< ml ent of acrylaiuide in t lie ci >poi\niei1 i he i ra nation r<iinpc- laMii'e i> shifted lo hijdici1 \".ihic-~. t h e 11 aiisit ii ni is iimcc 1^1 adiial ;nid sinallei1 fi'ai I inn of copulx'Uiei is pluihf se|>ai'a!ed. The same liehavionr \\-as fniind ior hiidn-i enntenl i if ct lianol or aeetnne in 1 he Mtlvent. If This emiteiit and t h e content ut" arrylaiuidi' is very ln,",li. the pliaM.' transition in dc pci i delice on the eompo-it ion of snh-cnl appejir- The relnxat ion cxpciinient- sh(J\\-cd ( ha! alter ihe |)hase -eparntion a p;nt...

See also: similar author names
16 ŠŤASTNÁ, Jana
2 Šťastna, Josef
16 Šťastná, Jana
2 Šťastná, Jana,
4 Šťastná, Jarmila
6 Šťastná, Jaroslava
4 Šťastná, Jitka
4 Šťastná, Johana
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