Please use this identifier to cite or link to this item:
|Title:||Polymer nanocomposite hydrogels exhibiting both dynamic restructuring and unusual adhesive properties||Authors:||Wang, M.
|Issue Date:||11-Jun-2013||Citation:||Wang, M., Yuan, D., Fan, X., Sahoo, N.G., He, C. (2013-06-11). Polymer nanocomposite hydrogels exhibiting both dynamic restructuring and unusual adhesive properties. Langmuir 29 (23) : 7087-7095. ScholarBank@NUS Repository.||Abstract:||Polymer nanocomposite (NC) hydrogels exhibiting both dynamic restructuring and unusual adhesive properties in wet and dry states have been prepared in an efficient and straightforward way via free radical polymerization of poly(ethylene glycol) methyl ether acrylate (PEG) in the presence of silane-modified sodium montmorillonite (NaMMT). The dynamic restructuring of the NC gel has been demonstrated by almost instant recovery of mechanical properties, such as storage modulus, loss modulus, and damping tan δ (at 0.025 strain) by 60-110% after being stressed to the point of gel failure. Furthermore, the dry NC gel showed exceptional thermal and mechanical stability during a heating and cooling cycle between 25 and 110 C, with only slightly decreases followed by at least 30% increases in both moduli, while tan δ remained nearly unchanged. The NC gel in dry state could repeatedly adhere to various surfaces such as steel, glass, plastic, etc., and detach from the surface without being broken and leaving little contamination behind. This unique adhesive characteristic was characterized by high storage modulus, loss modulus (kPa), and tan δ (>0.6) corresponding to high cohesive, adhesive, and tacking properties of pressure-sensitive adhesives (PSAs). Finally, a reversible network structure formed by PEO interpenetrating within 3-dimentional (3-D) silica network was proposed to be responsible for the dynamic restructuring and the unique adhesive behaviors observed in the NC gel, and the 3-D network structure was investigated by XRD, FTIR, and DSC measurements. For this 3-D network structure, we suggest that the flexibility of PEO could allow PEO side chains to contact with various surfaces by either PEO segments or methoxy end groups via weak physical interactions, such as van der Waals interactions or hydrogen bonding, whereas the reversible network structure contributes to the recovery of strength and shape after the gel failure. © 2013 American Chemical Society.||Source Title:||Langmuir||URI:||http://scholarbank.nus.edu.sg/handle/10635/86655||ISSN:||07437463|
|Appears in Collections:||Staff Publications|
Show full item record
Files in This Item:
There are no files associated with this item.
checked on Feb 28, 2018
WEB OF SCIENCETM
checked on Dec 31, 2018
checked on Apr 19, 2019
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.