A pre‐mold study of alkaline‐silane treated EFB‐PP composites based on thermal and rheological analysis

Abstract

Rheological and thermal properties are important parameters to understand the role of the numerous variables involved in manufacturing and to achieve a high‐quality final product. The composites were prepared by compounding polypropylene (PP) with treated (alkaline and silane) oil‐palm empty fruit bunch (EFB) fiber using a twin screw extruder. Generally, regardless of fiber loading, the thermal stability of EFBPP composites was increased after using alkaline and silane‐treated EFB fibers as reinforcement. DSC analysis shows that there is a change in the melting temperature (Tm) and the degree of crystallinity (Xc) values of the EFB composites. The melt flow rate (MFR) of the composites decreased while viscosity increased with an increase in fiber loading. Rheological analysis reveals the composites to have a viscoelastic solid behavior where storage modulus (G') is greater than loss modulus (G“). The composites exhibit predominantly viscous behaviour (G" > G') at lower frequencies, whereas at higher frequencies the composites exhibit elastic behavior (G' > G”). The decrement of complex viscosity (η*) with an increasing angular frequency (ω) shows the materials exhibit shear thinning behavior. The composites also show the ability for regeneration when analyzed using time‐dependent behavior.

Plant fiber‐reinforced composites based on injection molding process: Manufacturing, service life, and remanufacturing

“…The fibers in the matrix can form a fiber network that increases the solid‐like viscoelastic behavior of the composite. The higher the degree of dispersion of the plant fibers in the collective, the more pronounced this behavior is 123 . As the fiber content increases, the difference between the energy storage modulus and the energy dissipation modulus becomes smaller, and the viscous behavior of the composites will be weakened and show a transition from viscoelastic liquid to viscoelastic solid behavior.…”