Data-Driven Design of PLA/PBAT/MCC/HA Composites for Biodegradable Mulch Films

Conventional low-density poly(ethylene) (LDPE) agricultural mulch films generate persistent plastic waste, which has motivated the development of biodegradable mulch films (BDMs) that can provide adequate performance during use while offering improved end-of-life options. Here, composite films containing poly(lactic acid) (PLA), poly(butylene adipate-co-terephthalate) (PBAT), microcrystalline cellulose (MCC), and hydroxyapatite (HA) were evaluated for their material properties and suitability as agricultural mulches. Correlation analysis and Elastic Net regression were used to examine composition–property relationships. PBAT primarily governed ductility and tensile performance, whereas MCC significantly increased water absorption because of its hydrophilic character. Water absorption was the most reliably modeled response (training R2 = 0.893), while mechanical property models showed limited validation performance, which indicates that composition alone could not fully predict unseen formulations. Several formulations met commercial BDM mechanical requirements. Multi-objective optimization predicted a composition of 9.3/80.7/3.5/6.5 wt% PLA/PBAT/MCC/HA. The combined experimental and modeling framework clarifies composition–property relationships in biodegradable polymer composites and demonstrates how data-driven approaches can guide the formulation of biodegradable agricultural mulch films.