6533b7d7fe1ef96bd12690de

RESEARCH PRODUCT

Effect of sisal and hydrothermal ageing on the dielectric behaviour of polylactide/sisal biocomposites

P. Reig-rodrigoMonica EkEmma StrömbergJosé David BadiaJosé David BadiaR. Teruel-juanesAmparo Ribes-greusSigbritt KarlssonThorsak KittikornThorsak Kittikorn

subject

Dielectric spectroscopyMaterials scienceSegmental cooperativity02 engineering and technologyDielectric010402 general chemistry01 natural sciencesHydrothermal circulationSisalCrystallinityDegradationDynamic fragilityPoly(lactide) (PLA)Composite materialCrystallinitySISALcomputer.programming_languageBiocompositesMaterials compostosTermoplàsticsGeneral EngineeringHydrothermal ageingINGENIERIA DE LOS PROCESOS DE FABRICACION021001 nanoscience & nanotechnology0104 chemical sciencesDielectric spectroscopyNatural fibreAgeingMAQUINAS Y MOTORES TERMICOSCeramics and CompositesDegradation (geology)0210 nano-technologycomputer

description

[EN] The dielectric properties of virgin polylactide (PLA) and its reinforced composites with different weight amounts of sisal fibres were assessed at broad temperature (from - 130 degrees C to 130 degrees C) and frequency ranges (from 10(-2)-10(7) Hz), before and after being subjected to accelerated hydrothermal ageing. The synergetic effects of both the loading of sisal and hydrothermal ageing were analysed by means of dielectric relaxation spectra. The relaxation time functions were evaluated by the Havriliak-Negami model, substracting the ohmic contribution of conductivity. The intramolecular and intermolecular relaxations were respectively analysed by means of Arrhenius and Vogel-Fulcher-Tammann-Hesse thermal activation models. The addition of fibre increased the number of hydrogen bonds, which incremented the dielectric permittivity and mainly hindered the non-cooperative relaxations of the biocomposites by increasing the activation energy. Hydrothermal ageing enhanced the formation of the crystalline phase at the so-called transcrystalline region along sisal. This fact hindered the movement of the amorphous PLA fraction, and consequently decreased the dielectric permittivity and increased the dynamic fragility. (C) 2017 Elsevier Ltd. All rights reserved.

yearjournalcountryeditionlanguage
2017-01-01
10.1016/j.compscitech.2017.05.026https://dx.doi.org/10.1016/j.compscitech.2017.05.026