A comparative evaluation of the properties of eggshell-polyvinyl chloride films obtained by solution casting and co-precipitation techniques

This paper investigates the impact of the production methods on the tensile and thermal characteristics of polyvinyl chloride composite films. Untreated and vinyltrimethoxysilane-treated eggshells at various concentrations were utilized as fillers. The films are obtained via solution casting and co-precipitation techniques, and their tensile strength, elongation at break, and Young’s modulus were compared. The results indicate that the co-precipitation method ensures better dispersion of the filler in the polyvinyl chloride matrix, and films have almost twice as high values of tensile strength (up to 7.46 MPa) and Young’s modulus (up to 59.27 MPa) compared to those produced via solution casting (4.11 MPa and 34.5 MPa, respectively). The treatment of eggshells with vinyltrimethoxysilane enhances interfacial adhesion and further improves these characteristics. It was found for film 1:2 – polyvinyl chloride (PVC): vinyltrimethoxysilane-treated eggshell (VTMS-ES), an increase of about 30°C in the initial temperature of thermal degradation and a 12% reduction in mass loss compared to the same composition with untreated eggshells.