Effect of coupling agent content and water absorption on the mechanical properties of coir‐agave fibers reinforced polyethylene hybrid composites

Abstract

In this study, high-density polyethylene/agave-coir composites with two fiber contents (20 and 30 wt%) and different coir-agave fiber ratios (1-0, 0.8-0.2, 0.6-0.4, 0.4-0.6, 0.2-0.8, and 0-1) were produced in a twostep process using twin-screw extrusion followed by injection molding. The effect of mixing two different natural fibers and the addition of coupling agent on water absorption, mechanical properties, and morphology is reported. The rule of hybrid mixture was used to predict the properties of the composites, showing a good agreement with the experimental data. The results obtained showed that the combination of different fibers produces composites with unique characteristics as coir fibers absorb less water than agave fibers, while at the same time increase more tensile and flexural strengths. On the other hand, agave fibers were found to improve the impact strength of coir composites. Also, the effect of water absorption on the mechanical properties was studied. Finally, the use of a coupling agent had a positive effect on mechanical properties, while lowering water uptake. POLYM.

Dynamic Mechanical And Water Absorption Properties Of Microcrystalline Cellulose Reinforced Polypropylene Composites: The Effect Of Unconventional Irradiation Route

“…A lower crosslinking density, on the other hand, would only ease the diffusion of water molecules mainly in the amorphous parts [25]. Furthermore, the decrease in the water absorption in this work is similar to the case in natural fiber/polymer composites treated with coupling agent [26][27]. This observation indicates that the introduction of i-rPP was beneficial to improve resistance against water absorption.…”

Elastic modulus prediction for hybrid polymer composites

“…On the other hand, the data on ductility can be represented by a sigmoidal type of curve as obtained from the regression. But again, due to experimental un-certainty, the linear model (dashed line with b = 1 and c = 0) might also be sufficient as reported several time in the literature [6] . composites as a function of the volume fraction of the first component for data taken.…”

“…One important aspect of hybrid composites is that synergistic effects can be produced between the different reinforcement used leading to properties much higher than expected, especially when using the simple linear rule of hybrid mixtures (RoHM). [5,6] For example, Ramezani Kakroodi et al [7] combined different concentration of hemp fibers in polypropylene and observed that for a total hemp content of 20% wt., an optimum tensile modulus of 518 MPa was obtained for a 20/80 (weight ratio) of short/long fibers compared to a composite having 100% short fibers (425 MPa) or 100% long fibers (472 MPa). The effect was also seen at 30% wt.…”

Production and Characterization of Hybrid Polymer Composites Based on Natural Fibers

“…Natural and synthetic reinforcements combination has showed to improve several composite characteristics such as thermal stability [106,[112][113][114], impact strength [63,[115][116][117] and water uptake [70, 112-114, 118, 119]. But the combination of two different types of lignocellulosic fibers was shown to control water absorption [53,103,110] and increased impact strength [103,120], especially when using coupling agents.…”