Development and characterization of novel environmentally sustainable poly (lactic acid)/ball clay composite films

Abstract In this work, novel environmentally sustainable poly (lactic acid) (PLA)/ball clay composite films were prepared using a sonication‐assisted solution casting process, incorporating 1–5 wt% ball clay into the PLA matrix. The pristine and composite films of PLA were characterized for structural, chemical, morphological, tensile, thermal, UV–visible light transmittance, and color properties. No additional transmittance peaks were detected in the FTIR spectra of PLA/ball clay films compared with pristine PLA, demonstrating the physical nature of the interaction between PLA and ball clay. Interestingly, the PLA/ball clay films demonstrated excellent UV‐blocking properties without compromising transparency. Moreover, the reinforcement of ball clay showed a negligible impact on the melting temperature of the PLA‐based films. A decrease in lightness (+L*) and greenness (−a*) values, along with an increase in yellowness (+b*) values, was observed with increasing ball clay loading in the PLA‐based films. A ball clay concentration of 3 wt% was deemed optimal, as it resulted in a compact morphology for the PLA‐based films without any agglomerates. Notably, the PLA‐based films containing 3 wt% ball clay (PLA/3ball clay) demonstrated an increment in thermal degradation temperature from 337 to 352°C, an improvement in tensile strength from 32 to 48 MPa, and an enhancement in crystallinity from 19% to 23% compared with pristine PLA films. Highlights Preparation of novel poly (lactic acid) (PLA)/ball clay films. PLA/3ball clay films demonstrated a 1.5‐fold enhancement in tensile strength. Excellent UV‐blocking properties of composite films without losing transparency. No change in melting temperature with the loading of ball clay in PLA‐based films. PLA/3ball clay films showed a 15°C improvement in thermal degradation temperature.