Interfacial phenomena in starch/fumed silica at varied hydration levels

Gun'ko, VM; Pissis, P; Spanoudaki, A; Turova, AA; Turov, VV; Zarko, VI; Goncharuk, EV

dc.contributor.author	Gun'ko, VM	en
dc.contributor.author	Pissis, P	en
dc.contributor.author	Spanoudaki, A	en
dc.contributor.author	Turova, AA	en
dc.contributor.author	Turov, VV	en
dc.contributor.author	Zarko, VI	en
dc.contributor.author	Goncharuk, EV	en
dc.date.accessioned	2014-03-01T01:28:42Z
dc.date.available	2014-03-01T01:28:42Z
dc.date.issued	2008	en
dc.identifier.issn	0927-7757	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/18924
dc.subject	1H NMR spectroscopy	en
dc.subject	Cryoporometry	en
dc.subject	DRS	en
dc.subject	Fumed silica	en
dc.subject	Hydrogel	en
dc.subject	Starch	en
dc.subject	TSDC	en
dc.subject	Unfrozen water	en
dc.subject	Wetted powder	en
dc.subject.classification	Chemistry, Physical	en
dc.subject.other	Hydration	en
dc.subject.other	Nuclear magnetic resonance spectroscopy	en
dc.subject.other	Silica fume	en
dc.subject.other	Surface chemistry	en
dc.subject.other	Non-gelatinised starch	en
dc.subject.other	Wetted powders	en
dc.subject.other	Starch	en
dc.subject.other	nanoparticle	en
dc.subject.other	polymer	en
dc.subject.other	silicon dioxide	en
dc.subject.other	starch	en
dc.subject.other	analytic method	en
dc.subject.other	article	en
dc.subject.other	dielectric relaxation spectroscopy	en
dc.subject.other	freezing	en
dc.subject.other	high temperature	en
dc.subject.other	hydration	en
dc.subject.other	hydrogel	en
dc.subject.other	methodology	en
dc.subject.other	priority journal	en
dc.subject.other	proton nuclear magnetic resonance	en
dc.subject.other	spectroscopy	en
dc.subject.other	thermally stimulated depolarisation current method	en
dc.subject.other	thermodynamics	en
dc.title	Interfacial phenomena in starch/fumed silica at varied hydration levels	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.colsurfa.2008.02.004	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.colsurfa.2008.02.004	en
heal.language	English	en
heal.publicationDate	2008	en
heal.abstract	Hydrated powders of non-gelatinised starch and hydrogels of gelatinised starch alone or with addition of modified nanosilica (with grafted aminopropylmethylsilyl groups substituting one-third of surface silanols) were studied using broadband dielectric relaxation spectroscopy (DRS), thermally stimulated depolarisation current (TSDC) method and H-1 NMR spectroscopy with layer-by-layer freezing-out of bulk and interfacial waters. The H-1 NMR and TSDC techniques with the use of Gibbs-Thomson relation for the freezing point depression allow us to calculate: (i) the thermodynamic parameters of interfacial water weakly and strongly bound to polymer molecules and nanoparticles; (ii) size distributions of pores filled by structured water; (iii) surface area and volume of micro-, meso- and macropores. The DRS and TSDC results for hydrogels and hydrated powders with starch/modified fumed silica show that the beta- and gamma-relaxations of starch are strongly affected by water and functionalised silica nanoparticles which slow down both low- and high-frequency and low- and high-temperature relaxations. (C) 2008 Elsevier B.V. All rights reserved.	en
heal.publisher	ELSEVIER SCIENCE BV	en
heal.journalName	Colloids and Surfaces A: Physicochemical and Engineering Aspects	en
dc.identifier.doi	10.1016/j.colsurfa.2008.02.004	en
dc.identifier.isi	ISI:000256871100037	en
dc.identifier.volume	320	en
dc.identifier.issue	1-3	en
dc.identifier.spage	247	en
dc.identifier.epage	259	en