Tailoring the Microstructure of Biodegradable PLA/PBS Melt-Blown Nonwovens with Enhanced Mechanical Performance by In Situ PBS Fibrils Formation

Polylactide (PLA) has attracted attention for use in the melt blowing process due to its ease of processing and biodegradation. However, the low mechanical property limits the practical application. In this work, in situ fibrillation technology was introduced to improve the mechanical properties of PLA-based melt-blown nonwovens. First, PLA/PBS blends with a sea–island morphology were prepared using a screw extruder. Then, the PBS droplets evolved into in situ fibrils under the action of elongational flow and transverse contraction in the die and airflow field. Benefiting from the in situ fibrous structure, the simultaneous enhancement in strength (2.19 MPa) and strain (12.97%) was achieved in the PLA-based melt-blown nonwovens, obtaining a substantial increase of 164 and 672%, respectively, compared to the pure PLA nonwovens. Moreover, the prepared nonwovens exhibited enhanced thermal properties and good wearing comfort performance. Overall, this study proposes a simple and promising method for preparing biodegradable melt-blown nonwovens with excellent mechanical properties.