Thermal and Mechanical Enhancement of PVC Composites with Functionalized Asphaltene Fillers

The limited thermal and mechanical stability of polyvinyl chloride (PVC) restricts its application in more advanced industrial sectors. These limitations are overcome in the present research by adding up to 5 wt. % asphaltenes from crude oil, in its pristine or acid-functionalized form, enhancing compatibility with PVC. The material is prepared by dispersing asphaltene in tetrahydrofuran and combining it with PVC in the same solvent. After solvent removal, the composite is formed. Analysis shows successful integration of asphaltene, improving its thermal stability and mechanical strength. Mechanical testing showed that the tensile strength increased from 68.4 MPa (pure PVC) to 77 MPa at 2 wt.% pristine asphaltene, and to 71 MPa at 1 wt.% functionalized asphaltene, representing improvements of 12.6% and 9.6%, respectively. Elongation at break also improved, reaching 58.6% for 2 wt.% asphaltene compared to 4.99% for pure PVC. Optimal performance was observed at 2 wt.% asphaltene, with acid-functionalized asphaltene performing better at 1 wt.%. Microscopic imaging indicates homogeneous distribution at ideal concentrations, but larger loadings result in aggregation. This composite has potential uses in construction, automotive, and packaging.