MECHANICAL AND BIODEGRADABILITY PROPERTIES OF SYNTHESIZED BIO-MEMBRANES FROM WASTE HEMP FIBERS

Abstract

In this study, waste hemp fibers were transformed into cationically modified materials through a two-step process. The process began with the collection of agricultural waste fibers after hemp harvesting, followed by a delignification pretreatment, and subsequently, quaternization using the synthesized Deep Eutectic Solvent of chlorocholine chloride and urea. To form the material into membranes, modified fibers were cross-linked under pressure using citric acid as a natural cross-linker. The structural and chemical characteristics of the non-treated fibers (NtHF) and formed membranes were analyzed using SEM and FTIR techniques. The mechanical properties of the membranes were determined by measuring the breaking force and calculating the tensile strength via the Brazilian test method. Biodegradability was assessed by examining the mass loss of membranes composed of unmodified and cationized hemp fibers over 90 days, using a Soil Burial Test (AATCC Test Method 30-1993) in controlled laboratory conditions (24 °C). The results demonstrated a significant improvement in the tensile strength of the synthesized material (2.41 MPa), attributed to the synergistic effect of physical intermolecular interactions within the cationically modified hemp membranes (WCHM) and enhanced cross-linking using citric acid. The newly synthesized membrane showed great potential as a biodegradable material, with the first signs of degradation, reflected by a 25% mass loss, observed after 14 days. A slightly faster degradation rate was noted for non-treated fibers, highlighting the effectiveness of citric acid as a cross-linker.