Tremendous reinforcing, pore-stabilizing and response-accelerating effect of in situ generated nanosilica in thermoresponsive poly(N-isopropylacrylamide) cryogels

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389013%3A_____%2F17%3A00478890" target="_blank" >RIV/61389013:_____/17:00478890 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1002/pi.5406" target="_blank" >http://dx.doi.org/10.1002/pi.5406</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1002/pi.5406" target="_blank" >10.1002/pi.5406</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Tremendous reinforcing, pore-stabilizing and response-accelerating effect of in situ generated nanosilica in thermoresponsive poly(N-isopropylacrylamide) cryogels

Popis výsledku v původním jazyce

The tremendous reinforcing and pore-stabilizing effect of in situ formed nanosilica in a highly porous temperature-responsive poly(N-isopropylacrylamide) (PNIPA) matrix is demonstrated. A very weakly crosslinked semi-liquid hydrogel can be reinforced to the point that it displays a fast, extensive and nearly symmetric temperature-responsiveness in combination with an acceptable modulus. In soft but solid porous PNIPA, only 0.6 wt% of the nanofiller is sufficient to stabilize the pores against collapse upon de-swelling, thus enabling ultrafast responsiveness. A spectacular effect is achieved with dried porous PNIPA (matrix is glassy, Tg approximate to 140 °C), which in the case of optimal nanosilica amounts can re-swell in only 3 min. The key importance of efficient hydrogen bridging between PNIPA and SiO2 is demonstrated by comparing in situ formed nanosilica with similarly sized commercial Ludox particles, the surface of which is saturated with ammonia (for stabilization). Synthesis parameters like the amount of crosslinker and of nanosilica were varied in a wide range, in order to achieve the fastest possible responsiveness of the hydrogels in combination with a high modulus. The porosity, nanosilica distribution, moduli, temperature-dependent swelling as well as the swelling kinetics of the gels were determined as functions of contents of crosslinker and nanosilica.

Název v anglickém jazyce

Tremendous reinforcing, pore-stabilizing and response-accelerating effect of in situ generated nanosilica in thermoresponsive poly(N-isopropylacrylamide) cryogels

Popis výsledku anglicky

The tremendous reinforcing and pore-stabilizing effect of in situ formed nanosilica in a highly porous temperature-responsive poly(N-isopropylacrylamide) (PNIPA) matrix is demonstrated. A very weakly crosslinked semi-liquid hydrogel can be reinforced to the point that it displays a fast, extensive and nearly symmetric temperature-responsiveness in combination with an acceptable modulus. In soft but solid porous PNIPA, only 0.6 wt% of the nanofiller is sufficient to stabilize the pores against collapse upon de-swelling, thus enabling ultrafast responsiveness. A spectacular effect is achieved with dried porous PNIPA (matrix is glassy, Tg approximate to 140 °C), which in the case of optimal nanosilica amounts can re-swell in only 3 min. The key importance of efficient hydrogen bridging between PNIPA and SiO2 is demonstrated by comparing in situ formed nanosilica with similarly sized commercial Ludox particles, the surface of which is saturated with ammonia (for stabilization). Synthesis parameters like the amount of crosslinker and of nanosilica were varied in a wide range, in order to achieve the fastest possible responsiveness of the hydrogels in combination with a high modulus. The porosity, nanosilica distribution, moduli, temperature-dependent swelling as well as the swelling kinetics of the gels were determined as functions of contents of crosslinker and nanosilica.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10404 - Polymer science

Projekt

<a href="/cs/project/GA17-13103S" target="_blank" >GA17-13103S: Pokročilé inteligentní a samoregenerující se polymerní nanokompozity</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2017

Kód důvěrnosti údajů

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

Název periodika

Polymer International

ISSN

0959-8103

e-ISSN

—

Svazek periodika

66

Číslo periodika v rámci svazku

11

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

12

Strana od-do

1510-1521

Kód UT WoS článku

000412166000012

EID výsledku v databázi Scopus

2-s2.0-85021407215