abstract
The incorporation of cork in synthetic polymers has become an effective approach to develop new sustainable materials. Cork-polypropylene composites (CPC) filled with three different cork granulometries were studied. Rheological analyses were performed to assess the processability of these CPC and a set of experiments was conducted keeping the same matrix/cork weight ratio, varying the cork granulometric distribution. The effect of three different cork granulometries, temperature and the effect of a coupling agent, polypropylene graft maleic anhydride (PPgMA), were analysed. All composites exhibited non-Newtonian, pseudoplastic behaviour. Related to neat PP, cork incorporation led to a viscosity increase. This increase is more significant in the CPC with the lowest powder cork granulometry used. On the other side, the addition of PPgMA resulted on a decrease of CPC viscosity. The experimental results were fitted to Cross-WLF Model through a viscosity master curve obtained by the time-temperature superposition principle (TTSP). This study showed that cork can be considered on the development of sustainable materials for injection moulding technology. (C) 2016 Elsevier Ltd. All rights reserved.
keywords
MECHANICAL-PROPERTIES; MOLECULAR-WEIGHT; POLYPROPYLENE; FLOW
subject category
Engineering; Materials Science
authors
da Silva, SPM; Lima, PS; Oliveira, JM
our authors
J. Martinho Oliveira
Coordinator Professor
Sara Patrícia Magalhães da Silva
Junior Researcheracknowledgements
The authors are grateful to COMPETE - Programa Operacional Factores de Competitividade (POFC), project number 30176, for financial support.