Effect of fibre surface modifications on crystallization and thermal behaviour of poly lactic acid (PLA)-natural fibre composites

International Conference and Exhibition on Biopolymers & Bioplastics

August 10-12, 2015 San Francisco, USA

Emmanuel I1, Adeosun S O2, Lawal G I2 and Balogun S A3

Posters-Accepted Abstracts: J Material Sci Eng

Abstract :

Production of biodegradable polymer composites mostly presents the problem of poor interfacial adhesion between fibre and the
matrix. This challenge often results in poor crystallization ability and thermal responses resulting in poor service performance
of packaging and structural polymer composites. This study focuses on measuring the effectiveness of two recently developed
fibre surface modification paths on crystallization and thermal behaviour of PLA - natural fibre composites. Cellulosic fibres from
Groundnut shell (G), Coconut shell (C), Rice husk (R), Palm fruit bunch (PB) and Palm fruit stalk (PS) processed using two processing
paths (M1 and M2) are used as reinforcement in poly lactide (PLA) to produce biodegradable polymer composites for structural and
packaging applications. Crystallization and thermal responses of the composites are studied in relation to improvement in surface
adhesion of the fibres. Crystallization behaviour, melting, glass transition and cold crystallization temperatures are deduced from
Differential Scanning Calorimetry (DSC) thermograms. Results show that the introduction of fibres also led to a decrease of the coldcrystallization
temperature (Tcc) for all composites indicating that the fibres serve as nucleation sites for the onset of crystallization
of the composites. An increase in crystallinity of the composites (about 100%) over that of the virgin PLA is also observed, indicating
improved thermal and structural properties. The maximum crystallinity obtained in this study is higher than those of materials
currently used for packaging (bottles) by about 119% showing the suitability of the developed paths for processing natural fibres for
biodegradable packaging applications. The melting temperatures of all composites are found to be higher than that of virgin PLA
showing that the composites possess a higher molecular weight than PLA.