Biodegradable polylactic acid (PLA) melt-blown nonwovens are attractive candidates to replace non-degradable polypropylene melt-blown nonwovens. However, it is still an extremely challenging task to prepare PLA melt-blown nonwovens with sufficient mechanical properties for practical application. Herein, we report a simple strategy for the large-scale preparation of biodegradable PLA/poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) melt-blown nonwovens with high strength and excellent toughness. In this process, a small amount of PHBV is added to PLA to improve the latter’s crystallization rate and crystallinity. In addition, when the PHBV content increases from 0 to 7.5 wt%, the diameters of the PLA/PHBV melt-blown fibers decrease significantly (with the+ proportion of nanofibers increasing from 7.7% to 42.9%). The resultant PLA/PHBV (5 wt% PHBV) melt-blown nonwovens exhibit the highest mechanical properties. The tensile stress, elongation, and toughness of PLA/PHBV (5 wt% PHBV) melt-blown nonwovens reach 2.5 MPa, 45%, and 1.0 MJ·m^–3, respectively. More importantly, PLA/PHBV melt-blown nonwovens can be completely degraded into carbon dioxide and water after 4 months in the soil, making them environmentally friendly. A general tensile-failure model of melt-blown nonwovens is proposed in this study, which may shed light on mechanical performance enhancement for nonwovens.

可生物降解的聚乳酸（PLA）熔喷非织造布是替代不可降解聚丙烯熔喷非织造布的有吸引力的候选者。然而，制备具有足够机械性能以供实际应用的PLA熔喷非织造布仍然是一项极具挑战性的任务。在此，我们报告了一种大规模制备具有高强度和优异韧性的可生物降解PLA/聚（3-羟基丁酸酯-co-3-羟基戊酸酯）（PHBV）熔喷非织造布的简单策略。在此过程中，在PLA中添加少量的PHBV，以提高后者的结晶速率和结晶度。此外，当PHBV含量从0wt%增加到7.5wt%时，PLA/PHBV熔喷纤维的直径显着减小（纳米纤维的+比例从7.7%增加到42.9%）。所得的 PLA/PHBV (5 wt% PHBV) 熔喷非织造布表现出最高的机械性能。PLA/PHBV（5 wt% PHBV）熔喷非织造布的拉伸应力、伸长率和韧性分别达到2.5 MPa、45%和1.0 MJ·m ^–3。更重要的是，PLA/PHBV熔喷非织造布在土壤中放置4个月后即可完全降解为二氧化碳和水，对环境友好。本研究提出了熔喷非织造布的通用拉伸破坏模型，这可能有助于非织造布机械性能的增强。