Strain inhomogeneity effect on yielding of polymer nanocomposites

Spathis, G; Kontou, E

dc.contributor.author	Spathis, G	en
dc.contributor.author	Kontou, E	en
dc.date.accessioned	2014-03-01T01:29:14Z
dc.date.available	2014-03-01T01:29:14Z
dc.date.issued	2008	en
dc.identifier.issn	0032-3861	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/19176
dc.subject	Free volume distribution	en
dc.subject	Glassy state	en
dc.subject	Yielding	en
dc.subject.classification	Polymer Science	en
dc.subject.other	ABS resins	en
dc.subject.other	Deformation	en
dc.subject.other	Distribution functions	en
dc.subject.other	Free volume	en
dc.subject.other	Nanocomposites	en
dc.subject.other	Nanostructured materials	en
dc.subject.other	Photoresists	en
dc.subject.other	Polymers	en
dc.subject.other	Polystyrenes	en
dc.subject.other	Positron annihilation spectroscopy	en
dc.subject.other	Positrons	en
dc.subject.other	Free volume distribution	en
dc.subject.other	Glassy state	en
dc.subject.other	Polymer nano-composites	en
dc.subject.other	Post-yielding	en
dc.subject.other	Yielding	en
dc.subject.other	Functional polymers	en
dc.subject.other	deformation	en
dc.subject.other	nanocomposite	en
dc.subject.other	polystyrene	en
dc.subject.other	strain	en
dc.title	Strain inhomogeneity effect on yielding of polymer nanocomposites	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.polymer.2008.07.039	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.polymer.2008.07.039	en
heal.language	English	en
heal.publicationDate	2008	en
heal.abstract	In this work, yielding and post yielding effects are analyzed using the idea of the inhomogeneous distribution of strain in polymers under deformation. This idea is directly connected with the free volume concept, as created in the polymeric bulk during the frozen in process, and or the density fluctuations combined with other type defects. A simple strain density distribution function is assumed, following experimental results available from techniques such as positron annihilation lifetime spectroscopy (PALS). Hereafter, a functional form of the rate of plastic deformation is extracted, which will be combined with a given kinematic formulation. The proposed analysis is tested with experimental data of polystyrene (PS) and PS/SiO2 nanocomposites. The incorporation of nanosized fillers into the polymeric bulk, strongly affects the free volume distribution and/or the distribution of defects related with density fluctuations. This fact is reflected in the model parameter values, and their variation in respect to the different material types. With the proposed analysis, it has been proved that all features of yield process, including strain softening and strain hardening effect are easily described. (c) 2008 Elsevier Ltd. All rights reserved.	en
heal.publisher	ELSEVIER SCI LTD	en
heal.journalName	Polymer	en
dc.identifier.doi	10.1016/j.polymer.2008.07.039	en
dc.identifier.isi	ISI:000259715100019	en
dc.identifier.volume	49	en
dc.identifier.issue	20	en
dc.identifier.spage	4462	en
dc.identifier.epage	4468	en