Abstract
In this work, the effect of an acidic environment on the structure of composite samples based on ultra-high molecular weight polyethylene (UHMWPE) modified with mineral filler in the form of diabase (DB) is studied. The stability of samples was investigated in solutions of sulfuric (H₂SO₄) and hydrochloric (HCl) acids with concentrations of 10 vol% and 20 vol% at room temperature for 16 weeks. It was found that the introduction of 10 wt% DB into the UHMWPE matrix significantly increases the resistance of the composite sample to aggressive media, which is confirmed by the minimum degree of swelling compared to pure UHMWPE and composites with higher filler content. Scanning electron microscopy (SEM) demonstrated a uniform distribution of DB in the sample structure and the absence of defects such as agglomeration and cracks. The methods of infrared spectroscopy (IRS) and X-ray structural analysis (XRD) revealed a decrease in the degree of crystallinity of the samples after acid exposure, but no significant changes in the chemical structure of the materials were recorded, which confirms their resistance to chemical degradation. The best chemical resistance was demonstrated by composites containing 10 wt% DB, which is associated with the formation of a barrier structure preventing the diffusion of acids. The obtained results indicate the promising application of UHMWPE with DB filler to create samples resistant to aggressive media.