Thermo-responsive sandwiched-like membranes of IPN-PNIPAAm/PAAm hydrogels

dc.creatorGuilherme, MR
dc.creatorCampese, GM
dc.creatorRadovanovic, E
dc.creatorRubira, AF
dc.creatorTambourgi, EB
dc.creatorMuniz, EC
dc.date2006
dc.dateAPR 20
dc.date2014-11-20T05:44:23Z
dc.date2015-11-26T17:15:34Z
dc.date2014-11-20T05:44:23Z
dc.date2015-11-26T17:15:34Z
dc.date.accessioned2018-03-29T00:03:48Z
dc.date.available2018-03-29T00:03:48Z
dc.identifierJournal Of Membrane Science. Elsevier Science Bv, v. 275, n. 41671, n. 187, n. 194, 2006.
dc.identifier0376-7388
dc.identifierWOS:000236455200023
dc.identifier10.1016/j.memsci.2005.09.019
dc.identifierhttp://www.repositorio.unicamp.br/jspui/handle/REPOSIP/58178
dc.identifierhttp://www.repositorio.unicamp.br/handle/REPOSIP/58178
dc.identifierhttp://repositorio.unicamp.br/jspui/handle/REPOSIP/58178
dc.identifier.urihttp://repositorioslatinoamericanos.uchile.cl/handle/2250/1282076
dc.descriptionThe synthesis of sandwiched-like IPN hydrogels having cross-linked PNIPAAm interpenetrated into PAAm networks was carried out by UV-induced polymerization using potassium periodate as a sensitizer. NIPAAm monomers and MBAAm cross-linker were co-polymerized inside previously synthesized cross-linked PAAm. Through SEM images, we observed that the hydrogel membranes were formed by three layers; the internal layer was fully involved by the two others. Significant morphological difference between the internal and external layers was also observed. Thus, sandwiched-like interpenetrating polymer networks were obtained. The internal layer shrank significantly after warming the swollen hydrogel above LCST of PNIPAAm in water, 30-35 degrees C while the external layers remained swollen and highly porous due to the hydrophilicity of PAAm. The experiments performed at 40 degrees C revealed that the hydrogels shrank considerably. Collapsed PNIPAAm chains induced a substantial contraction of the internal hydrogel layer. The hydrogel contraction was accompanied by an increase in gel strength and elasticity modulus. The presence of the PNIPAAm network in the internal layer reinforced the hydrogel and this effect was more pronounced above LCST. The permeability of sandwich-like membrane significantly rather decreases as the temperature increases. There was a decrease in the permeability of 52% as the temperature was increased from 25 to 40 degrees C. It was suggested that the structural changes in the sandwich membrane induce to significant flux control. (c) 2005 Elsevier B.V. All rights reserved.
dc.description275
dc.description41671
dc.description187
dc.description194
dc.languageen
dc.publisherElsevier Science Bv
dc.publisherAmsterdam
dc.publisherHolanda
dc.relationJournal Of Membrane Science
dc.relationJ. Membr. Sci.
dc.rightsfechado
dc.rightshttp://www.elsevier.com/about/open-access/open-access-policies/article-posting-policy
dc.sourceWeb of Science
dc.subjectsandwich-like membrane
dc.subjectNIPAAm
dc.subjectacrylamide
dc.subjectmorphology
dc.subjectmechanical properties
dc.subjectInterpenetrating Polymer Networks
dc.subjectTemperature-sensitive Membranes
dc.subjectCompressive Elastic-modulus
dc.subjectMechanical-properties
dc.subjectPolyacrylamide Hydrogels
dc.subjectN-isopropylacrylamide
dc.subjectSemi-ipns
dc.subjectPoly(n-isopropylacrylamide)
dc.subjectWater
dc.subjectSurface
dc.titleThermo-responsive sandwiched-like membranes of IPN-PNIPAAm/PAAm hydrogels
dc.typeArtículos de revistas


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