Development and Characterization of Novel Polylactic Acid/Calcium Fluoride Biocomposite Films: Effects on Structural, Mechanical, Thermal, and Optical Properties

Abstract

Novel biocomposite films produced from polylactic acid (PLA)/calcium fluoride (CaF2) have been developed and characterized in this study through solvent casting methods. The PLA matrix was incorporated with CaF2 powder at different concentrations (0.5-30 wt%), which can keep the biodegradability but improved material properties. The structural, mechanical, thermal, and optical effects of varying CaF2 content were discussed using XRD, FTIR, SEM, TGA, DSC, and mechanical tests. About 30 wt% increases in the tensile strength of the P30 sample (30 wt% CaF2) have shown to be significantly improved, from 9.3% to 30.6% by CaF2 supplement. SEM analysis showed that due to excessive CaF2 loading, points of stress concentration and hence surface cracks appeared indicating the loading limit. Thermal analysis proved to improve stability at higher amounts of CaF2 (>5 wt%), shown in TGA results with reduced mass loss and ash content. However, with increasing CaF2 content, the optical properties were compromised, resulting in more opaque and yellowish films. All of this showed that, however, CaF2 appears to be a very good reinforcing agent for PLA, optimum loading must be weighed for mechanical, thermal, and optical properties. It is evidence toward the improvement of enhanced PLA-based biocomposites for numerous applications, maintaining environmental sustainability.