Blends based on poly(lactic acid) : structure/rheology/processing relationship
type: Distribution
access URL: https://theses.hal.science/tel-00876617
format: HTML
issued: 2026-05-09T06:17:44.629991
modified: 2026-05-09T06:17:44.595727

test_moissonnage_selune
type: Agent

Blends based on poly(lactic acid) : structure/rheology/processing relationship
type: Dataset
contact point: Organization
  fn: CCSD
keyword: etirage-bi-axial
keyword: chain-extension
keyword: pbat
keyword: melange-de-polymeres
keyword: polymers-blend
keyword: epoxyde
keyword: theses
keyword: extrusion-gonflage
keyword: spiotherengineering-sciences-physicsother
keyword: bi-axial-stretching
keyword: infoeu-reposemanticsdoctoralthesis
keyword: relation-microstructure-proprietes
keyword: blowing-extrusion
keyword: rheology
keyword: relationship-between-microstructure-and-properties
keyword: polylactic-acid
keyword: shear
keyword: cisaillement
keyword: rheologie
keyword: epoxide
keyword: extension-de-chaine
keyword: compatibilisation
keyword: compatibilization
keyword: polyacide-lactique
landing page: https://theses.hal.science/tel-00876617
description: The ultimate aim of the present thesis focuses on the structure/processing/properties relationship of the PLA/PBAT materials. The latters are intended for food packaging in order to replace poly (ethylene terephthalate (PET). However, PLA has a limited processability in conventional technologies of plastics industry. The strengthening of its melt properties has been achieved through the incorporation of a multifunctional epoxide, able to react with the end chains of polyesters. Furthermore, PLA/PBAT blends were prepared to make the final material more ductile. The first part of the study consists on the understanding of thermal and hydrolytic degradation mechanisms of neat PLA and PBAT polymers upon processing. Indeed, the degradation was overcome through the chain extension reaction coupled to branching, induced by the multifunctional epoxide. The chain extension and branching mechanisms were highlighted by the analysis of the activation energy and the relaxation spectra in the molten state as well as the physico-chemical properties in solution. Moreover, the Van-Gurp-Palmen plots confirm the co-existence of linear and randomly branched macromolecular chains. The second part has been dedicated to the compatibilization of PLA/PBAT blends by the multifunctional epoxide. Experimental models studies, based on the assessment of the interfacial tension, and the rheological modeling showed the major role of the reactive epoxide agent as a compatibilizer. Thus, the decrease of the interfacial tension gives a better cohesive interface with finer and homogenous morphology of the dispersed phase, accompanied with an improvement of the mechanical properties. The study of the shear and elongation rheological properties of modified materials showed an enhancement of their melt strength. Therefore, a better ability to be blown has been demonstrated, by expanding their stability maps. Besides, biaxial stretching studies of neat polymers, their modified counterparts as well as thei…
identifier: NNT: 2012ISAL0116
issued: 2026-05-09T06:17:44.618683
language: en
modified: 2026-05-09T06:17:44.618687