Effect of surface modification and fiber content on the mechanical performance of compression molded polyethylene-maple composites

With the objective of producing more sustainable materials, wood-plastic composites were produced using linear low density polyethylene and a wide range of maple wood fiber content (up to 80% wt). This was possible by using a simple dry-blending of the component in a powder form and compression molding. In particular, the effect of different surface treatments (mercerization, maleated polyethylene [MAPE], and their combination) on the morphology and mechanical performance of these composites was studied. The results show that all the surface treatments investigated were able to improve the fiber-matrix adhesion, leading to better composite homogeneity, and higher mechanical properties. Furthermore, it was possible to increase the amount of wood that can be introduced in the composites compared to untreated fibers. In our case, up to 80% wt of maple fibers were easily processed generating significant improvements in moduli (367%) and strength (50%), especially when a combination of alkali-MAPE treatment was performed. This simple processing of the composites is interesting to produce different parts size and geometry with limited degradation since no melt compounding is performed. The work also represents a way to produce sustainable, economic, and lightweight composites with improved properties using a high content of renewable filler.

Automated summary

By using simple processing methods and different surface treatments, the mechanical properties and homogeneity of wood-plastic composites can be improved, especially when using Maleated Polyethylene (MAPE) treatment. Utilizing a high content of maple fibers can lead to significant improvements in the properties of the composites.