Show simple item record

dc.contributor.authorRikkou-Kalourkoti, Maria D.en
dc.contributor.authorKitiri, E. N.en
dc.contributor.authorPatrickios, Costas S.en
dc.contributor.authorLeontidis, Epameinondasen
dc.contributor.authorConstantinou, Marthaen
dc.contributor.authorConstantinides, G.en
dc.contributor.authorZhang, X. K.en
dc.contributor.authorPapadakis, Christine M.en
dc.creatorRikkou-Kalourkoti, Maria D.en
dc.creatorKitiri, E. N.en
dc.creatorPatrickios, Costas S.en
dc.creatorLeontidis, Epameinondasen
dc.creatorConstantinou, Marthaen
dc.creatorConstantinides, G.en
dc.creatorZhang, X. K.en
dc.creatorPapadakis, Christine M.en
dc.date.accessioned2019-11-21T06:22:34Z
dc.date.available2019-11-21T06:22:34Z
dc.date.issued2016
dc.identifier.urihttp://gnosis.library.ucy.ac.cy/handle/7/56077
dc.description.abstractThis study presents the preparation and characterization of double networks (DN) based on a first amphiphilic polymethacrylate conetwork (APCN) and a second polyacrylamide network. The APCN first network comprised interconnected "in-out" star copolymers of 2-(dimethylamino)ethyl methacrylate (DMAEMA, hydrophilic ionizable monomer) and 2-ethylhexyl methacrylate (EHMA, hydrophobic comonomer) or lauryl methacrylate (LauMA, second hydrophobic comonomer), synthesized using group transfer polymerization, following one-pot, sequential, monomer, and hydrophobic cross-linker (ethylene glycol dimethacrylate, EGDMA) additions. The second network was prepared by the aqueous photopolymerization of acrylamide (AAm) at two different concentrations, 2 and 5 M, and N,N′-methylenebis(acrylamide) cross-linker in the presence of the fully ionized (via HCl addition) APCN. After synthesis, all DNs and single (first and second) (co)networks, equilibrium-swollen in water, were characterized in terms of their mechanical properties in compression. The DNs exhibited improved mechanical properties (stress and strain at break, and elastic modulus) compared to the corresponding single networks. Better reinforcement was achieved in the DNs whose APCN first networks bore a lower hydrophobic content and whose hydrophobic monomer was EHMA rather than LauMA. The best DN exhibited stress at break above 8 MPa and strain at break nearly 80%, close to the values of the best DNs in the literature. Nanoindentation studies were also performed on selected DNs which proved again the enhanced mechanical properties of the present DNs, manifested as high resistance to penetration and low creep displacement. Small-angle X-ray scattering (SAXS) indicated a broad correlation peak for all APCN first networks, suggestive of microphase separation with short-range order, arising from the presence of the hydrophobic segments. The single correlation peak was preserved in the SAXS profiles of the DNs, which was, however, shifted to lower q-values, consistent with further network swelling. Despite the SAXS evidence for only weak phase separation on the nanoscale in the DNs, half of the water-swollen DNs (the ones with a 5 M AAm concentration in the second network) exhibited strong birefringence which probably arose from the stretching of the charged DMAEMA segments rather than the presence of anisotropic nanophases. © 2016 American Chemical Society.en
dc.sourceMacromoleculesen
dc.source.urihttps://www.scopus.com/inward/record.uri?eid=2-s2.0-84960361971&doi=10.1021%2facs.macromol.5b02490&partnerID=40&md5=fdfa889fb08d9e5a79ba79018c3615a9
dc.subjectMechanical propertiesen
dc.subjectStressesen
dc.subject2-(dimethylamino)ethyl methacrylateen
dc.subjectMonomersen
dc.subjectBlock copolymersen
dc.subjectHydrophilicityen
dc.subjectHydrophobicityen
dc.subjectStrainen
dc.subjectPolymer blendsen
dc.subjectPhase separationen
dc.subjectPhotopolymerizationen
dc.subjectEthyleneen
dc.subjectGroup transfer polymerizationen
dc.subjectEthylene glycolen
dc.subjectHydrophobic monomersen
dc.subjectEthylene glycol dimethacrylateen
dc.subjectAmidesen
dc.subjectX ray scatteringen
dc.subjectPolyacrylatesen
dc.subjectMicrophase separationen
dc.subjectHydrophobic contenten
dc.subjectAqueous photopolymerizationen
dc.subjectShort range orderingen
dc.subjectStar block copolymeren
dc.titleDouble Networks Based on Amphiphilic Cross-Linked Star Block Copolymer First Conetworks and Randomly Cross-Linked Hydrophilic Second Networksen
dc.typeinfo:eu-repo/semantics/article
dc.identifier.doi10.1021/acs.macromol.5b02490
dc.description.volume49
dc.description.issue5
dc.description.startingpage1731
dc.description.endingpage1742
dc.author.faculty002 Σχολή Θετικών και Εφαρμοσμένων Επιστημών / Faculty of Pure and Applied Sciences
dc.author.departmentΤμήμα Χημείας / Department of Chemistry
dc.type.uhtypeArticleen
dc.description.notes<p>Cited By :12</p>en
dc.source.abbreviationMacromoleculesen
dc.contributor.orcidPatrickios, Costas S. [0000-0001-8855-0370]
dc.contributor.orcidLeontidis, Epameinondas [0000-0003-4427-0398]


Files in this item

FilesSizeFormatView

There are no files associated with this item.

This item appears in the following Collection(s)

Show simple item record