Poly(ethylene-co-vinyl acetate) (PECoVA) composite containing organophilic microcrystalline dolomite (OMCD) was studied to replace the non-recyclable silicone elastomer in biomedical application. Pristine dolomite (DOL) is an inorganic mineral filler and is hydrophilic in nature, hence incompatible with most polymers and limits its use in biomedical applications. DOL was subjected to a combination of size reduction, tip sonication and a surface modification process to obtain a more effective dolomite filler, known as OMCD, as reinforcement material in the PECoVA copolymer matrix. The effects of DOL and OMCD loadings (1, 3, 5 wt%) on the structure and properties of the PECoVA composite were investigated. According to the X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), tensile and tear tests, dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC) analysis, the use of the OMCD filler brought a more pronounced positive impact to the PECoVA matrix as opposed to the DOL, where it enhanced the crystallinity of the matrix and led to much better matrix–filler interfacial interactions. Therefore, regardless of the filler loading, the PECoVA/OMCD composites demonstrate greater mechanical and thermal properties compared to the PECoVA/DOL composites. The best composite was produced with the OMCD loading of 3 wt%, in which the tensile strength (22.1 MPa), elongation at break (1413%) and Young’s modulus (2.0 MPa) of the copolymer matrix were increased by 44%, 23% and 21%, respectively. This proved that the combination of size reduction, tip sonication and the surface modification technique is efficient to obtain the PECoVA/dolomite composite with improved performance.

This study investigates the effects of nanocellulose crystal (NCC) and nanocellulose fibre (NCF) additives on the thermal ageing resistance and biodegradation behavior of poly(3-hydroxybutyrate-co-3-hydroxyvalerate)/natural rubber (PHBV/NR) blends. Nanocomposites containing 0–5 wt% of NCC or NCF were prepared and subjected to thermal ageing and soil burial tests. Thermal ageing results showed that both NCC and NCF enhanced the pre-ageing mechanical properties of PHBV/NR blends, with NCC providing slightly superior performance. Soil burial tests revealed that nanocellulose additives significantly improved the biodegradability of the blends, with NCF showing more pronounced effects at lower concentrations. FTIR analysis indicated subtle changes in chemical structure during degradation, while optical microscopy analyses demonstrated significant morphological changes in nanocellulose-containing samples after soil burial. The contact angle results show that NCFs significantly increase hydrophilicity because of their fibrous morphology and network formation. The optimal nanocellulose concentration for enhanced biodegradability was found to be around 3% for both types, with PHBV/NR/NCF3 exhibiting the highest overall weight loss of 27.0% after 42 days. This study highlights the potential of nanocellulose additives in developing biodegradable polymer nanocomposites with tailored degradation profiles and improved long-term performance for applications requiring thermal stability and controlled biodegradability.

Extrusion blow molding (EBM) is widely used for manufacturing plastic products, with low-density polyethylene (LDPE) being a key material due to its flexibility and processability. However, its high consumption contributes significantly to plastic waste accumulation and the depletion of non-renewable resources. Recycling LDPE is a promising approach to reducing plastic waste, but multiple reprocessing cycles and blending can alter the properties, potentially affecting product quality and performance. Grasping the degradation mechanisms and property retention of LDPE blends is essential for upholding product quality while advancing sustainability. This research investigates the impacts of recycled LDPE (rLDPE) and re-recycled LDPE (rrLDPE) on LDPE blends, focusing on physical, flow behavior, mechanical, structural, morphological and thermal properties. The findings indicate that moisture content and density increased with higher recycled content due to oxidation, while melt flow index (MFI) increased, which implies a reduced in molecular weight. Both tensile and impact strength diminished, with FESEM further revealed brittle fracture features especially in rrLDPE blends, underscoring ongoing polymer degradation leading to mechanical deterioration. Fourier transform infrared spectroscopy (FTIR) analysis verified oxidative alterations through increased hydroxyl (-OH) and carbonyl (C=O) functional groups, while differential scanning calorimetry (DSC) results indicated a reduction in crystallinity from 49.17% (vLDPE) to 34.23% (rrLDPE), confirming structural degradation. Blends with ≤30 wt% rLDPE maintained acceptable performance, while rrLDPE content exceeding 10 wt% led to significant deterioration. These findings provide insights into optimizing sustainable LDPE formulations, balancing environmental benefits with material integrity.

Poly (vinylidene fluoride‑co‑hexafluoropropylene) (PVDF‑HFP) polymer inclusion membranes (PIMs) are widely used across separation industries because of their ability to selectively separate ions or molecules, their chemical stability, and their mechanical flexibility. Still, improving how the membrane performs without making the membrane material properties deteriorate remains a challenge. In this study, Aliquat 336 and Cyphos IL 104 were blended with PVDF‑HFP and fabricated through the solvent casting method. The main objective of this study is to understand how the ionic liquids can affect the membrane’s chemical properties, physical properties, mechanical stability, and its ability to recover gold through an H-cell setup. FTIR analysis confirmed the presence of Aliquat 336, showing bands associated with quaternary ammonium groups, while Cyphos IL 104 displayed vibrations related to phosphonium‑related P–C. SEM images further revealed clear differences in how the membrane morphology looked. Pure PVDF-HFP alone had compact surfaces; Aliquat 336 membranes appeared to have smoother features, and Cyphos IL 104 membranes developed rougher surfaces with micro-voids. The addition of ionic liquids also increased membrane porosity from 25 % in the pure membrane to 45 % with the addition of ionic liquids. At the same time, the contact angle dropped from 90° to 58°, indicating improved hydrophilicity. Mechanical testing showed that pure PVDF‑HFP had the highest tensile strength (30 MPa), modulus (450 MPa), and tear resistance (2.5 N/mm). Membranes with higher Aliquat 336 content retained better tear resistance, close to 2.0 N/mm, while maintaining smoother membrane surfaces. In comparison, the addition of Cyphos IL 104 adversely impacts the mechanical properties. Gold extraction experiments showed promising performance. The PVDF-HFP/A15C20 membrane achieved 76 % recovery within 12 h. The combination of both Aliquat 336 and Cyphos IL 104 improved ion transport while maintaining acceptable membrane stability properties. Overall, the results showed that the ionic liquid composition has a strong influence on both the membrane’s durability properties and separation performance. These findings provide a useful approach for developing membranes in precious metal recovery applications.

The efficient recovery of gold from acidic aqueous solutions is vital for sustainable resource management and high-value metal recycling. In this work, poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) polymer inclusion membranes (PIMs) incorporating chitosan (CS) nanoparticles (0–2.0 wt.%) and Aliquat 336 as the ionic carrier were fabricated via solvent casting and comprehensively characterized. FTIR analysis confirmed intermolecular interactions between CS and PVDF-HFP through hydrogen bonding, while SEM revealed that moderate CS loading (1.5 wt.%) enhanced surface roughness and pore uniformity, whereas excessive loading (2.0 wt.%) induced nanoparticle aggregation. Contact angle and water uptake measurements showed progressively improved hydrophilicity with CS incorporation, correlating with increased aqueous phase accessibility. Thermogravimetric analysis and Coats–Redfern modelling indicated a slight reduction in thermal stability and activation energy with increasing CS content, attributed to thermally unstable CS functional groups and disruption of PVDF-HFP crystallinity. Gold adsorption experiments analyzed by ICP-OES demonstrated consistently high removal efficiencies for all membranes, with a maximum of 99.92% at 2.0 wt.% CS. Kinetic analysis revealed excellent fitting of both pseudo-first-order (PFO) and pseudo-second-order (PSO) models (R ² ≥ 0.981). The highest adsorption rate constants were observed at 1.5 wt.% CS, confirming rapid uptake dominated by a chemisorption mechanism. Overall, moderate CS incorporation (1.5 wt.%) provided the optimal balance between enhanced hydrophilicity, ion-binding capacity, and structural integrity, offering valuable insights for the design of sustainable, bio-based PIMs for efficient precious metal recovery.