Production and Characterization of High Density Polyethylene Reinforced by Eucalyptus Capsule Fibers

In this work, Eucalyptus Capsule Fibers （ECF） are proposed as a new natural fiber reinforcement to produce bio-composites due to their biological origin, specific smell and color. High Density Polyethylene （HDPE） is used as the matrix to compare three reinforcement types, raw ECF, alkali treated ECF, and ECF treated with PE-graft-maleic anhydride （PE-g-MA） as a coupling agent at three concentrations （5 wt.%, 10 wt%, and 15 wt%）. A complete set of characterization is performed including tension, torsion, hardness, Melt Flow Index （MFI）, Attenuated Total Reflection Fourier Transform Infrared Spectroscopy （ATR-FTIR）, Contact Angle （CA）, Scanning Electron Microscopy （SEM）, Thermogravimetric Analysis （TGA） and Dynamic Mechanical Analysis （DMA）. The results show that the best mechanical and rheological improvements are obtained by using the coupling agent with alkali treated fibers.

A Comparison between Sabra and Alfa Fibers in Rubber Biocomposites

The main objective of this investigation is to valorize a Moroccan crop residue(Sabra fibers,Agave Americana L.)and to compare with Alfa fibers(,Stipa tenacissima L.)as reinforcement in an elastomeric matrix in term of the relaxation properties,mechanical and rheological properties.The preparation and properties of these two natural fibers embedded in Styrene-Butadiene Rubber(SBR)are presented with and without the addition of Styrene-Ethylene-Butadiene-Styrene grafted with Maleic Anhydride(SEBS-g-MA)as a coupling agent.Five different series(SBR,SBR/Alfa,SBR/Alfa/SEBS,SBR/Sabra and SBR/Sabra/SEBS)were compounded by extrusion and compression molding.As a result,the addition of the coupling agent in the elastomeric matrix improves the relaxation properties,mechanical and rheological properties.Moreover,Sabra fibers show the good results compared to Alfa fibers.Finally,the Zener model was used to determine the rheological time response of the composites.A good agreement between the experimental data and the model was observed(R^2=0.99).

Laminated Epoxy Biocomposites Based on Clay and Jute Fibers

Jute/epoxy hybrid laminated biocomposites were manufactured by using Illite clay particles at various content （5 wt.% - 20 wt.%）. The effects of hybridization on the morphology, structure, and mechanical properties were investigated. The properties of the biocomposites reinforced with jute fibers were mainly influenced by the interfacial adhesion between the jute fibers and the epoxy matrix. An alkali treatment was applied to improve the interfacial fiber-matrix adhesion and thus obtaining better mechanical properties. Besides the chemical treatment, epoxy hybridization using clay particles also had a strong effect on the overall properties of laminated biocomposites. The mechanical properties of the jute/epoxy biocomposites reinforced with Illite clay increased with clay content, up to an optimum value at 15 wt.%. The average technique and the laminates theory were performed to validate the coherence of the elastic moduli between the calculated and experimental values. A difference between the experimental and predicted data was observed, which was attributed to the simplifying assumptions made in both models. The laminates theory gave better overall predictions.