Mechanical characterization of asymmetric high density polyethylene/hemp composite sandwich panels with and without a foam core

Abstract

This work investigates the effects of different design parameters such as hemp content in the skins (10-40% wt.), layer thickness (1 and 2 mm), and foaming agent content in the core (0% wt., 0.6% wt. and 1.2% wt.) on the flexural properties of three layer sandwich panels of hemp and high density polyethylene produced by compression molding. The results show that hemp content was the most significant parameter for the flexural properties of these panels. In addition, it was found that specific modulus and strength (per unit weight) were 30% and 36% higher when using a foam core, respectively.

Determination of the optimum coupling agent content for composites based on hemp and high density polyethylene

“…Therefore, a next step would be to prepare composites with different hemp content with 9% MAPE and characterized them to evaluate the effect of hemp content on the mechanical properties of these composites. Some results can be found in other publications [14,16].…”

“…The compounds were first preheated for 3 minutes, then pressed for 5 minutes in a mold with dimensions of 250 × 250 × 3 mm 3 . More details on the materials and methods can be obtained elsewhere [14].…”

Low Velocity Impact Behaviour of Asymmetric Three-layer Sandwich Composite Structures with and without Foam Core

“…For instance, increasing hemp content in both skins from 10% (10(1)-0-10(2)) to 40% (40(1)-0-40(2)), improved the peak load from 3518 to 4459 N which is an increase of 27%. This can be associated with the stiffness of 10(1)-0-10(2) and 40(1)-0-40(2) which were reported to be 1124 and 1676 MPa, respectively 21 . Moreover, the effect of increasing hemp content in the top skin to improve the peak load is more pronounced than for the bottom skin.…”

“…As an example, the peak load value of 10(2)-0-10(1) is 3236 N, while the value increased to 3751 N for 40(2)-0-10(1) and to 3474 N for 10(2)-0-40(1) which are about 16% and 7% improvement, respectively. This is directly related to structure stiffness for 10(2)-0-10(1), 40(2)-0-10(1) and 10(2)-0-40(1) which were 1205, 1466, and 1405 MPa, respectively 21 .…”

“…The findings in terms of energy/force, load-deflection response, and failure mode are discussed to enable a better understanding of their impact responses. This report is actually a continuous effort to understand the mechanical response of polymer sandwich panels where the morphology, density, and flexural properties of these structures were previously measured and discussed 21 . These results are used here to explain the impact response observed.…”