Characterization Study of Empty Fruit Bunch (EFB) Fibers Reinforcement in Poly(Butylene) Succinate (PBS)/Starch/Glycerol Composite Sheet

In this study, a mixture of thermoplastic polybutylene succinate (PBS), tapioca starch, glycerol and empty fruit bunch fiber was prepared by a melt compounding method using an industrial extruder. Generally, insertion of starch/glycerol has provided better strength performance, but worse thermal and water uptake to all specimens. The effect of fiber loading on mechanical, morphological, thermal and physical properties was studied in focus. Low interfacial bonding between fiber and matrix revealed a poor mechanical performance. However, higher fiber loadings have improved the strength values. This is because fibers regulate good load transfer mechanisms, as confirmed from SEM micrographs. Tensile and flexural strengths have increased 6.0% and 12.2%, respectively, for 20 wt% empty fruit bunch (EFB) fiber reinforcements. There was a slightly higher mass loss for early stage thermal decomposition, whereas regardless of EFB contents, insignificant changes on decomposition temperature were recorded. A higher lignin constituent in the composite (for high natural fiber volume) resulted in a higher mass residue, which would turn into char at high temperature. This observation indirectly proves the dimensional integrity of the composite. However, as expected, with higher EFB fiber contents in the composite, higher values in both the moisture uptake and moisture loss analyses were found. The hydroxyl groups in the EFB absorbed water moisture through formation of hydrogen bonding

Characterisation and antimocrobial activity of poly(lacitc acid)/kenaf bio-composites containing a natural agent

The use of materials based on poly(lactic acid) (PLA) as alternatives to petroleum-based polymers for a range of applications has increased in recent years. In the case of food packaging in particular, PLA has experienced growth in combination with the use of a wide range of other materials and/or additives derived from natural and renewable resources. However, the initial costs associated with new technologies to produce PLA and/or other bio-based polymers are typically high, so new techniques are required to reduce costs without compromising material properties and biodegradability. Naturally sourced lignocellulose fibres such as kenaf (Hibiscus cannabinus L.) are often used as cost-reducing fillers and/or reinforcing agent for biopolymers such as PLA. This study explores the characteristics and antimicrobial (AM) activity of PLA and PLA/kenaf composites incorporated with thymol, a natural bio-active AM substance/agent. The production of PLA/kenaf composites containing thymol is intended for potential use in AM packaging applications such as rigid and/or flexible packaging and coatings. Composites of PLA incorporated with 5 to 40% w/w kenaf fibre loadings and thymol concentrations ranging from 5 to 30% w/w were prepared and compared with control systems containing either no kenaf or no thymol. Kenaf fibres can be treated by alkalisation to improve compatibility with polymer matrices. It was found that the PLA/kenaf composites containing treated kenaf possessed significantly higher tensile strength and stiffness than composites prepared with untreated kenaf. Micrograph images of the fracture surface revealed better adhesion between the treated kenaf fibres and the matrix, thereby resulting in improved reinforcement of the composite. Moreover, PLA/kenaf composites containing thymol exhibited lower tensile strength than those without thymol, suggesting a possible plasticizing effect in the presence of the additive

Effect of Poly(Lactic Acid)/Kenaf Composites Incorporated with Thymol on the Antimicrobial Activity of Processed Meat

Bio-based composites comprised of poly(lactic acid) (PLA), kenaf fibers and thymol were developed and their antimicrobial (AM) properties and stability under different storage conditions investigated. The composite films containing 20-30% w/w thymol reduced E. coli in tryptone soy broth after two days at 37C and imparted a significant zone of inhibition in contact with E. coli inoculated plates. The composite films also reduced E. coli inoculated on the surface of processed sliced chicken samples after 30 days at 10C both in direct contact and in the vapour phase. The thymol additive was retained in the PLA/kenaf films that were wrapped with aluminium foil after 3 months of storage at ambient temperatures; however, unwrapped films lost some thymol to the atmosphere. The PLA/kenaf/thymol composite films show a strong potential for the development of active packaging systems in order to extend the shelf-life of some processed food products