High-Density Polyethylene/Graphene Polymer Nanocomposites Used as Geogrids

Abstract

This study investigates the development of high-density polyethylene (HDPE) nanocomposites reinforced with graphene (G), aiming to apply them in the production of geogrids for geotechnical use. Nanocomposites with varying graphene contents (0.01%, 0.05%, and 0.10% w/w) were produced through melt extrusion, followed by injection and compression molding. The formulation containing 0.01% graphene exhibited better dispersion, higher crystallinity, fewer clusters, and superior mechanical and thermomechanical properties. HDPE-G-0.01% geogrids manufactured via laser cutting were subjected to direct shear tests in compacted dry sandy soil. The results indicated an increase in shear strength from a normal stress of approximately 100 kPa; consequently, a friction angle of 4.3° was achieved compared to neat HDPE geogrid, with no changes in the design or geometry of the geogrid. The performance gain is attributed to the enhanced interfacial interaction between soil and geogrid promoted by graphene. This study demonstrates the technical and economic feasibility of using graphene in ultra-low concentrations to produce high-performance civil engineering geosynthetics, with potential for large-scale industrial application and minimal impact on final cost.