Monolithic nanocomposite hydrogels with fast dual T- and pH- stimuli responsiveness combined with high mechanical properties

Strachota, Beata; Strachota, Adam; Horodecka, Sabina; Šlouf, Miroslav; Dybal, Jiří

doi:https://dx.doi.org/10.1016/j.jmrt.2021.11.018

Number of the records: 1

Monolithic nanocomposite hydrogels with fast dual T- and pH- stimuli responsiveness combined with high mechanical properties

1.

SYSNO ASEP	0548968
Document Type	J - Journal Article
R&D Document Type	Journal Article
Subsidiary J	Článek ve WOS
Title	Monolithic nanocomposite hydrogels with fast dual T- and pH- stimuli responsiveness combined with high mechanical properties
Author(s)	Strachota, Beata (UMCH-V)_RID Strachota, Adam (UMCH-V)_{RID, ORCID} Horodecka, Sabina (UMCH-V)_{RID, ORCID} Šlouf, Miroslav (UMCH-V)_{RID, ORCID} Dybal, Jiří (UMCH-V)_{RID, ORCID}
Source Title	Journal of Materials Research and Technology-JMR&T. - : Elsevier - ISSN 2238-7854 Roč. 15, November–December (2021), s. 6079-6097
Number of pages	19 s.
Language	eng - English
Country	BR - Brazil
Keywords	poly(N-isopropylacrylamide) ; clay ; nanocomposite
Subject RIV	CD - Macromolecular Chemistry
OECD category	Polymer science
R&D Projects	GA19-04925S GA ČR - Czech Science Foundation (CSF)
Method of publishing	Open access
Institutional support	UMCH-V - RVO:61389013
UT WOS	000726796200006
EID SCOPUS	85120349073
DOI	10.1016/j.jmrt.2021.11.018
Annotation	Monolithic (non-porous) nanocomposite hydrogels were synthesized, with double and ultra-fast stimuli-responsiveness to temperature (T) and to pH. Such a fast stimulus-response is exceptional in case of bulk gels, and the prepared hydrogels additionally possess extraordinarily high tensile, mechanical, and self–recovery properties. The presented materials might be of interest as actuators, drug- or reagent-release systems. They are based on poly(N-isopropylacrylamide) (PNIPAm) physically crosslinked by clay nanoplatelets. This crosslinking lends the gels their unique mechanical properties, PNIPAm a distinct T responsiveness, and the sodium methacrylate (SMA) co-monomer (just 1.5 mol%) a strong pH-responsiveness. The gels display a quasi-one-way and complex response to T- and pH-stimuli: very fast deswelling and slow re-swelling. Extremely fast, as for monolithic gels, is the T induced deswelling at pH2: ca. 10 min are needed for the whole process. This rapid kinetics is attributed to micro-phase-separation which does not destroy mechanical properties. Re-swelling of the gels is always slow: more than 2 days are needed for 35% completion of the process in case of gels shrunken in the neutral bath. In case of gels shrunken in acidic conditions, simple re-swelling is practically blocked (due to the micro-phase-separation): both cooling and pH reversal is needed for ‘un-blocking’ and re-swelling.
Workplace	Institute of Macromolecular Chemistry
Contact	Eva Čechová, cechova@imc.cas.cz ; Tel.: 296 809 358
Year of Publishing	2022
Electronic address	https://www.sciencedirect.com/science/article/pii/S2238785421012977?via%3Dihub

Number of the records: 1