Structures and interactions in collapsed hydrogels of thermoresponsive interpenetrating polymer networks

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F15%3A10318091" target="_blank" >RIV/00216208:11320/15:10318091 - isvavai.cz</a>

Alternative codes found

RIV/61389013:_____/15:00441899

Result on the web

<a href="http://dx.doi.org/10.1007/s00396-014-3455-x" target="_blank" >http://dx.doi.org/10.1007/s00396-014-3455-x</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1007/s00396-014-3455-x" target="_blank" >10.1007/s00396-014-3455-x</a>

Result language

angličtina

Original language name

Structures and interactions in collapsed hydrogels of thermoresponsive interpenetrating polymer networks

Original language description

Temperature-induced collapse of hydrogels of interpenetrating polymer networks (IPNs) poly(N-vinylcaprolactam)/poly(N-isopropylacrylamide) (PVCL/PNIPAm) and poly(N-isopropylmethacrylamide) (PNIPMAm)/PNIPAm, where both components are thermoresponsive, was studied by combination of H-1 nuclear magnetic resonance (NMR) spectroscopy, small-angle neutron scattering (SANS), differential scanning calorimetry (DSC), and dynamic mechanical measurements. Behavior of studied hydrogels (one or two transitions) was found to depend on the ratio of both IPN components. For hydrogels of IPNs containing around 50 mol% of PNIPAm monomer units, separate transitions were revealed for both components. From SANS curves, it follows that compact three-dimensional multi-chain globules are formed in PNIPMAm/PNIPAm and PVCL/PNIPAm IPN hydrogels at temperatures above the phase transition, with a gyration radius of 14-28 nm. A certain portion of spatially restricted bound water (HDO) was established for all the studied IPNs at temperature above the volume phase transition from measurements of H-1 NMR spectra, spin-spin relaxation times (T-2), and diffusion coefficients (D) of HDO. Slow exchange regime between bound and free water was revealed. Spin-spin relaxation times (T-2) and diffusion coefficients (D) as obtained for the bound HDO are up to 2 orders of magnitude smaller in comparison with "free" HDO. Higher content of bound water as found for collapsed hydrogels of IPN PVCL/PNIPAm in comparison with PNIPMAm/PNIPAm hydrogels is in accordance with swelling experiments and lower values of the shear mechanical modulus; this shows the decisive role of bound water in this respect.

Czech name

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Czech description

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Type

J_x - Unclassified - Peer-reviewed scientific article (Jimp, Jsc and Jost)

CEP classification

CD - Macromolecular chemistry

OECD FORD branch

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Project

<a href="/en/project/GA13-23392S" target="_blank" >GA13-23392S: Designing and characterization of novel thermosensitive polymer hydrogels</a><br>

Continuities

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

Publication year

2015

Confidentiality

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

Name of the periodical

Colloid and Polymer Science

ISSN

0303-402X

e-ISSN

—

Volume of the periodical

293

Issue of the periodical within the volume

3

Country of publishing house

DE - GERMANY

Number of pages

12

Pages from-to

709-720

UT code for WoS article

000350367200005

EID of the result in the Scopus database

2-s2.0-84925536722