| Titre : | Comportement rhéologique et propriétés thermophysiques, mécaniques et microscopiques des polymères chargés en relation avec l’interface et la taille des particules |
| Auteurs : | Fouzia Zoukrami ; Nacerddine Haddaoui, Directeur de thèse |
| Type de document : | texte imprimé |
| Editeur : | Sétif : Universite Ferhat Abbes faculté des sciences de l’ingénieur département de génie des procédés, 2009 |
| ISBN/ISSN/EAN : | TS4/7812 |
| Format : | 1 vol. (161 f.) / ill. |
| Note générale : | Bibliogr.Annexes |
| Langues: | Français |
| Catégories : | |
| Résumé : |
The main objective of this work is to prepare and to study polypropylene /untreated silica composites (PP/SiO2) by mixing in the melt state. A new processing method is developed and is used in order to reduce the size of aggregates of silica from the micrometer to the nanometre scale. This method is based on injection of water into a twin screw extruder with the incorporation of a second polar polymer phase. The effects of different compatibilizers, processing methods and conditions have been evaluated to understand the mechanisms of dispersion and quality of the polymer-filler interface. Studies of morphology, rheological behaviour, mechanical and thermal properties of PP/SiO2 composites were also evaluated to determine the parameters for obtaining a material with optimal properties. The state of dispersion showed the presence of individual particles and aggregates particles which have a size of 200nm for the composite containing the second polar phase of polyamide. An improvement of the dispersion and impact strength was also observed in the presence of glycerol monostearate (GMS) compatibilizer. While the presence of PP-g-MA coupling agent led to an increase in the tensile strength and modulus. All the mechanical properties have been improved with the second phase of polyamide compatibilizer, the change of thermal and rheological behaviour was observed to be directly dependent on the state of dispersion. Thermal parameters indicate also that silica plays the role of nucleation agent for PP matrix. In the second part of this work PP/clay composites were also prepared by solution blending process and in the melt state. The compounds were investigated by Transform Infra Red Spectroscopy (FTIR), and optical microscopy. The rheological, thermal and mechanical properties were evaluated to study the effect of PP-g-MA compatibilizer, stearic acid treatment and the type of clay (montmorillonite and kaolin) on the interfacial interaction and the degree of dispersion of fillers particles in PP matrix. The presence of polar groups of coupling agent gives a better dispersion and thermal properties show that clay acts also as nucleation agent for PP matrix. |
Exemplaires (1)
| Cote | Support | Localisation | Disponibilité |
|---|---|---|---|
| TS4/7812 | Thèse | Bibliothèque centrale | Disponible |
Accueil
