Effect of PBAT content on performance of PLA based degradable blend slice and composite meltblown nonwovens

Taking polylactic acid (PLA) as matrix, poly(butylene adipate-co-terephthalate) (PBAT) as toughening agent and polyethylene glycol (PEG) as plasticizer and compatibilizer, PLA/PBAT/PEG blends with different PBAT contents were prepared by melt-blending method using twin-screw granulator, and the melt index, thermal stability and brittle fracture section morphology of the blended slices were analyzed. The results show that PEG has a good plasticizing and capacitating effect on PLA/PBAT composite matrix, which makes PBAT uniformly dispersed in PLA matrix, showing a typical "island" structure and improving the toughness of PLA matrix. The PLA/PBAT/PEG composite meltblown nonwovens were fabricated by a reciprocating meltblown machine. The effects of PBAT content on the thermal properties, microstructure and mechanical properties of composite meltblown nonwovens were investigated by synchronous thermal analyzer, scanning electron microscopy and electronic universal testing machine. The tensile test results show that proper amount of PBAT and PEG can play a synergistic role in strengthening and toughening PLA-based composite meltblown nonwovens. Compared with pure PLA meltblown nonwovens fabricated by identical process, the PLA-3 (mass fraction of PBAT in PLA/PBAT composite matrix is 3%) meltblown nonwovens displays a 48.8% increment in transverse breaking strength and a 28.7% reinforcement in longitudinal breaking strength, meanwhile the transverse and longitudinal breaking elongation shows an improvement higher than two-fold.