STRUCTURAL AND PHYSICO-MECHANICAL PROPERTIES OF GEOMEMBRANES BASED ON RECYCLED POLYOLEFINS MODIFIED WITH ARGILLITE FROM THE SHERABAD DEPOSIT

This study investigated the effect of argillite, sourced from the local Sherabad deposit and modified with maleic anhydride, on the physical and mechanical properties of geomembranes based on recycled high-density polyethylene (r-HDPE), recycled low-density polyethylene (r-LDPE), and recycled polypropylene (r-PP). Maleic anhydride was used as a compatibilizer to ensure interfacial adhesion between the polymer matrix in the hydrophilic filler and the layered aluminosilicates, and to promote the uniform distribution of mineral particles. The experimental results showed that hybrid modification makes it possible to elevate the strength properties of all types of recycled polymers to the level of their virgin (pure) analogues and even surpass them. Specifically, the highest tensile strength (32.8 MPa) and puncture resistance (840 N) were recorded in the r-PP system, while the r-LDPE matrix exhibited an anomalous increase in its elongation at break of up to 710%, along with an increase in strength to 18.2 MPa. The article explains the fundamental scientific mechanisms underlying this effectiveness: the functional groups of maleic anhydrides form strong chemical bonds with the argillite surface, acting as crystallization centers (nucleating agent) in r-HDPE and r-PP composites. In the r-LDPE system, however, they create a hybrid "sliding layer" effect that efficiently heals macromolecular degradation and microcracks (filling effect). The resulting composite geomembranes demonstrated high chemical and thermal stability against aggressive saline soil conditions and harsh climatic factors.