Crystallization kinetics of polypropylenes. Effect of nucleating agents?

Abstract : Thermal conditions and formulation affect the crystallization mechanisms of polymers and the associated kinetics in a coupled manner. In that field, the objective of this investigation is to compare overall crystallization kinetics and structural organization of one clarified polypropylene (specifically designed for stretch-blow molding) and a homopolypropylene. Liquid/solid transitions are investigated in- and ex-situ under isothermal and non-isothermal conditions combining crossed-polarized optical microscopy, differential scanning calorimetry and X-ray diffraction. Clarified polypropylene has a very 'singular behavior' compared to homopolymer since no spherulites can be observed. However, it exhibits a semi-crystalline structure. The major α-phase coexists with some γ-phase even under quiescent conditions. Overall crystallization kinetics is rapid suggesting the existence of very efficient nucleating agent(s) and resulting in an increase of crystallization temperature. In parallel, the melting temperature of copolymer decreases by 20 °C compared to homopolymer, suggesting a drastic change in lamellae thickness. It is concluded that this unusual structure results from nucleation, which enforces high temperature crystallization, and copolymerization, which constraints the crystalline organization.
Type de document :
Communication dans un congrès
Liste complète des métadonnées

Littérature citée [7 références]  Voir  Masquer  Télécharger

https://hal-mines-paristech.archives-ouvertes.fr/hal-00510261
Contributeur : Magalie Prudon <>
Soumis le : mercredi 18 août 2010 - 11:41:43
Dernière modification le : lundi 12 novembre 2018 - 10:58:19
Document(s) archivé(s) le : mardi 23 octobre 2012 - 12:26:43

Fichier

esaform2008_boyer1.pdf
Fichiers produits par l'(les) auteur(s)

Identifiants

Citation

Séverine A.E. Boyer, Noëlle Billon, Jean-Marc Haudin. Crystallization kinetics of polypropylenes. Effect of nucleating agents?. 11th ESAFORM Conference on Material Forming, Apr 2008, Lyon, France. pp.Pages 603-606, ⟨10.1007/s12289-008-0328-1⟩. ⟨hal-00510261⟩

Partager

Métriques

Consultations de la notice

219

Téléchargements de fichiers

269