Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE An asymmetric trilayer PPDO-based membrane with reinforced interfacial bonding is fabricated via hot pressing and electrospinning. The hierarchical structure integrates hydrophilic, transitional, and hydrophobic layers to simultaneously enhance mechanical integrity, prevent delamination, and promote tissue regeneration, offering a biodegradable platform for postoperative anti-adhesion and dural repair applications.

ABSTRACT
Electrospun heterogeneous multilayer membranes have attracted increasing attention for biomedical tissue repair owing to their degradation behavior and favorable biocompatibility. However, delamination caused by weak interfacial bonding often compromises their mechanical stability and structural integrity. To address this challenge, a hot-pressing technique was employed to reinforce the interfacial adhesion of electrospun poly(p-dioxanone) (PPDO)-based composite membranes. Controlled hot-pressing conditions induced intimate fusion between adjacent layers, thereby enhancing interlayer bonding and overall mechanical strength. An asymmetric trilayer configuration was subsequently constructed, consisting of an upper hydrophilic and highly aligned PPDO nanofiber layer, a middle PPDO flat film serving as a transitional bonding layer, and a lower hydrophobic PPDO/poly(lactic acid) (PLA) composite nanofiber layer fabricated via dual-needle electrospinning. This hierarchical architecture offers functional differentiation while maintaining structural integrity. The lower hydrophobic PPDO/PLA layer acts as a barrier against fluid penetration, the middle PPDO film serves as a transitional bonding layer that ensures interfacial continuity, while the upper hydrophilic PPDO layer facilitates cell adhesion and tissue regeneration. This interfacial reinforcement strategy enables the fabrication of biodegradable and functionally graded composite membranes that achieve a balance between structural integrity and degradability, offering a promising platform for postoperative anti-adhesion and tissue regeneration applications.