Thermoresponsive double network hydrogels composed of poly(N-isopropylacrylamide) and polyacrylamide

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F19%3A10405289" target="_blank" >RIV/00216208:11320/19:10405289 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=N1RzFyYlnq" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=N1RzFyYlnq</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.eurpolymj.2019.04.032" target="_blank" >10.1016/j.eurpolymj.2019.04.032</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Thermoresponsive double network hydrogels composed of poly(N-isopropylacrylamide) and polyacrylamide

Popis výsledku v původním jazyce

Temperature response of double network (DN) hydrogels composed of thermoresponsive poly(N-isopropylacrylamide) (PNIPAAm) and hydrophilic polyacrylamide (PAAm) was studied by a combination of swelling and mechanical measurements, differential scanning calorimetry (DSC) and H-1 nuclear magnetic resonance (NMR) spectroscopy. A series of DN hydrogels with tightly crosslinked first network of PNIPAAm and loosely crosslinked second network of PAAm was prepared. In the series, crosslinking density of the first PNIPAAm network was varied while crosslinking density of the second PAAm network was kept constant. Presence of the second hydrophilic PAAm component in DN hydrogels strongly affects their behavior. Both, degree of deswelling and specific enthalpy of demixing in DN hydrogels are strongly reduced relative to corresponding single network (SN) hydrogels. Presence of the second network shows a reinforcing effect on DN hydrogels. From NMR results it follows that mobility of a great part of PNIPAAm in DN hydrogels is significantly reduced due to agglomeration of PNIPAAm induced by formation of the second network already at low temperature. A certain portion of water confined in agglomerated structures and a slow exchange regime between &quot;confined&quot; and &quot;free&quot; water were established by NMR methods for all investigated SN and DN hydrogels.

Název v anglickém jazyce

Thermoresponsive double network hydrogels composed of poly(N-isopropylacrylamide) and polyacrylamide

Popis výsledku anglicky

Temperature response of double network (DN) hydrogels composed of thermoresponsive poly(N-isopropylacrylamide) (PNIPAAm) and hydrophilic polyacrylamide (PAAm) was studied by a combination of swelling and mechanical measurements, differential scanning calorimetry (DSC) and H-1 nuclear magnetic resonance (NMR) spectroscopy. A series of DN hydrogels with tightly crosslinked first network of PNIPAAm and loosely crosslinked second network of PAAm was prepared. In the series, crosslinking density of the first PNIPAAm network was varied while crosslinking density of the second PAAm network was kept constant. Presence of the second hydrophilic PAAm component in DN hydrogels strongly affects their behavior. Both, degree of deswelling and specific enthalpy of demixing in DN hydrogels are strongly reduced relative to corresponding single network (SN) hydrogels. Presence of the second network shows a reinforcing effect on DN hydrogels. From NMR results it follows that mobility of a great part of PNIPAAm in DN hydrogels is significantly reduced due to agglomeration of PNIPAAm induced by formation of the second network already at low temperature. A certain portion of water confined in agglomerated structures and a slow exchange regime between &quot;confined&quot; and &quot;free&quot; water were established by NMR methods for all investigated SN and DN hydrogels.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10301 - Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect)

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2019

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

European Polymer Journal

ISSN

0014-3057

e-ISSN

—

Svazek periodika

116

Číslo periodika v rámci svazku

Neuveden

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

10

Strana od-do

415-424

Kód UT WoS článku

000471736700042

EID výsledku v databázi Scopus

2-s2.0-85064518446