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dc.contributor.authorShi, Guangyu
dc.contributor.authorGuan, Yu
dc.contributor.authorLiu, Guoming
dc.contributor.authorMüller Sánchez, Alejandro Jesús ORCID
dc.contributor.authorWang, Dujin
dc.date.accessioned2020-02-25T17:19:55Z
dc.date.available2020-02-25T17:19:55Z
dc.date.issued2019-09-04
dc.identifier.citationMacromolecules 52(18) : 6904-6912 (2019)es_ES
dc.identifier.issn0024-9297
dc.identifier.issn1520-5835
dc.identifier.urihttp://hdl.handle.net/10810/41446
dc.description.abstractHow segmental mobility influences the crystallization behavior of polymers in confined spaces is still not fully understood. In the present work, a systematic study of the segmental dynamics was carried out by dielectric relaxation spectroscopy (DRS) on racemic poly(DL-lactic acid) (PDLLA) confined in nanoporous alumina. The effect of pore size and thermal history were examined. Two glass transition temperatures (Tg) were observed, and an unusual “hysteresis” of the segmental relaxation time was detected. At lower temperatures, the segmental mobility of PDLLA “speeds up” firstly and “slows down” upon annealing. Both effects indicate the dynamically heterogeneous and nonequilibrium nature of chain segments under confinement. The “equilibrating process” of the relaxation time was monitored by DRS and the characteristic time exhibited Arrhenius behavior. The experimental evidence supports a reversible adsorption/desorption mechanism of chain segments. The enhanced cold crystallization of poly(lactic acid) (PLLA) we reported previously (Macromolecules 2015, 48 (8), 2526-2533) can be explained adequately with the “enhanced mobility” of segments. This was further justified by the shift of the cold crystallization temperature towards high temperatures of infiltrated PLLA after annealing.es_ES
dc.description.sponsorshipThis work is supported by the National Key R&D Program of China (2017YFE0117800) and the National Natural Science Foundation of China (21873109, 51820105005). G.L. is grateful to the Youth Innovation Promotion Association of the Chinese Academy of Sciences (2015026) and the Open Research Fund of State Key Laboratory of Polymer Physics and Chemistry (CIAC) (201510). A.J.M. gratefully acknowledges the financial support from MINECO through project MAT2017-83014-C2-1-P. G.L., D.W., and A.J.M. acknowledge European funding by the RISE BIODEST project (H2020-MSCA-RISE-2017-778092). G.S. thanks Dr. Wensheng Bu for assistance with the DRS measurement.es_ES
dc.language.isoenges_ES
dc.publisherACS Publicationses_ES
dc.relationinfo:eu-repo/grantAgreement/EC/H2020/778092es_ES
dc.relationinfo:eu-repo/grantAgreement/MINECO/MAT2017-83014-C2-1-Pes_ES
dc.rightsinfo:eu-repo/semantics/openAccesses_ES
dc.subjectCrystallizationes_ES
dc.subjectQuantum confinementes_ES
dc.subjectAnnealing (metallurgy)es_ES
dc.subjectPolymerses_ES
dc.subjectMolecular dynamicses_ES
dc.titleSegmental Dynamics Govern the Cold Crystallization of Poly(lactic acid) in Nanoporous Aluminaes_ES
dc.typeinfo:eu-repo/semantics/articlees_ES
dc.rights.holderCopyright © 2019 American Chemical Societyes_ES
dc.relation.publisherversionhttps://pubs.acs.org/doi/10.1021/acs.macromol.9b00542es_ES
dc.identifier.doi10.1021/acs.macromol.9b00542
dc.contributor.funderEuropean Commission
dc.departamentoesCiencia y tecnología de polímeroses_ES
dc.departamentoeuPolimeroen zientzia eta teknologiaes_ES


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