Rheological behavior of concentrated suspensions as affected by the dynamics of the mixing process

Kalyon, DM; Dalwadi, D; Erol, M; Birinci, E; Tsenoglu, C

dc.contributor.author	Kalyon, DM	en
dc.contributor.author	Dalwadi, D	en
dc.contributor.author	Erol, M	en
dc.contributor.author	Birinci, E	en
dc.contributor.author	Tsenoglu, C	en
dc.date.accessioned	2014-03-01T01:25:05Z
dc.date.available	2014-03-01T01:25:05Z
dc.date.issued	2006	en
dc.identifier.issn	0035-4511	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/17537
dc.subject	Mixedness	en
dc.subject	Mixing	en
dc.subject	Rheology	en
dc.subject	Suspension	en
dc.subject	Suspension rheology	en
dc.subject.classification	Mechanics	en
dc.subject.other	Elasticity	en
dc.subject.other	Elastomers	en
dc.subject.other	Electric properties	en
dc.subject.other	Graphite	en
dc.subject.other	Mixing	en
dc.subject.other	Particle size analysis	en
dc.subject.other	Rheology	en
dc.subject.other	Suspensions (fluids)	en
dc.subject.other	Thermogravimetric analysis	en
dc.subject.other	Viscosity	en
dc.subject.other	X ray diffraction analysis	en
dc.title	Rheological behavior of concentrated suspensions as affected by the dynamics of the mixing process	en
heal.type	journalArticle	en
heal.identifier.primary	10.1007/s00397-005-0022-x	en
heal.identifier.secondary	http://dx.doi.org/10.1007/s00397-005-0022-x	en
heal.language	English	en
heal.publicationDate	2006	en
heal.abstract	The rheological characterizations of concentrated suspensions are generally carried out assuming ""well-mixed"" suspensions. However, the variation of the concentration distributions of the ingredients of the formulation, i.e., the ""goodness of mixing"", the size and shape distributions of the particle clusters and the rheological behavior of the suspension all depend on the thermo-mechanical history that the suspension is exposed to during the mixing process. Here, various experimental tools are used for the characterization of the degree of mixedness (concentration distributions) of various ingredients along with the characterization of rheological material functions, wall slip behavior and the maximum packing fraction of a graphite/elastomer suspension. The degree of mixedness values of the ingredients of the suspensions processed using batch and continuous processes and under differing operating conditions were characterized quantitatively using wide-angle X-ray diffraction and thermo gravimetric analysis and were elucidated under the light of the electrical properties of the suspension as affected by the mixing process. Upon achieving better homogeneity of the graphite particles and the binder and decreases in the size and breadth of the size distributions of particle clusters (as inferred from electrical measurements and maximum packing fraction values), the elasticity (storage modulus) and the shear viscosity (magnitude of the complex viscosity from small-amplitude oscillatory shear and shear viscosity from steady torsional and capillary rheometry) of the suspension decreased significantly and the wall slip velocity values increased. These findings demonstrate the intimate relationships that exist between the rheological behavior of concentrated suspensions and the thermo-mechanical history that they are exposed to during the processing stage and suggest that the preparation conditions for suspensions should be carefully selected and well documented to achieve reproducible characterization of rheological material functions. © Springer-Verlag 2006.	en
heal.publisher	SPRINGER	en
heal.journalName	Rheologica Acta	en
dc.identifier.doi	10.1007/s00397-005-0022-x	en
dc.identifier.isi	ISI:000239002000013	en
dc.identifier.volume	45	en
dc.identifier.issue	5	en
dc.identifier.spage	641	en
dc.identifier.epage	658	en