Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE PBAT/PBS biodegradable compounds with high amounts of talc are produced via twin screw extrusion. After drying, the pellets are processed into sheets via cast extrusion and then thermoformed into trays using lab-scale equipment. The incorporation of talc lowers the material cost and allows obtaining trays with well-balanced thermal and structural performances.

ABSTRACT
Thermoformed plastic trays are extensively utilized in the food delivery sector and significantly contribute to landfill waste. The primary constraint on the widespread adoption of bioplastics in this domain is their elevated cost, which diminishes their market competitiveness. This study assessed the processability of compatibilized polybutylene adipate terephthalate (PBAT) and polybutylene succinate (PBS) with high talc loadings to mitigate costs. Talc was incorporated at 30 wt% (T733 formulation) and at 40 wt% (T734 formulation) within a PBAT/PBS 70/30 matrix. The blends were produced via twin screw extrusion and subsequently processed via cast extrusion and thermoforming to fabricate trays. These trays exhibit superior mechanical properties, as evidenced by the absence of breakage during compression testing, attributable to the highly flexible polymeric matrix. T734 demonstrated increased rigidity and reduced elongation at break, a consequence of the elevated talc content. Talc enhances the viscosity of the compounds. The measured melt flow rate (MFR) was 1.27 g/cm3 for T733 and 0.90 g/cm3 for T734, confirming the thermoformability of both compounds. By incorporating talc into compatibilized blends of PBAT and PBS, it is possible to produce bio-based trays with properties and costs comparable to those of currently used fossil-based alternatives.