Strengthened and Thermally Resistant Poly(lactic acid)-Based Composite Nanofibers Prepared via Easy Stereocomplexation with Antibacterial Effects

Abstract

Strengthened poly­(lactic acid) (PLA)-based materials with improved mechanical performance and improved thermal resistance, notably, are prepared by introducing stereocomplex crystallite (SC), an ideal filler, into the materials. Owing to the intermolecular hydrogen bond among the stereoisomer chains, the melting point of the special crystallite is up to 200 °C, which is 50 °C higher than the isostatic crystallite. The modulus of the PLA-based materials can be enhanced to several 100 MPa because of the integrated polymer chain arrangement. In this study, we electrospun hybrid nanofibers consisted of PLA stereoisomers and induced the stereocomplex crystallization under a mild condition (65 °C for 1 h). The mild warming is favorable for the protection of chlorogenic acid (CA) that was selected as the antibacterial agent. Both of Gram-positive and Gram-negative bacteria were efficiently cleared away using the warmed nanofibers that released CA rapidly within just a few hours. Used as filters, the SC electrospinning membrane also presented a potent filtering effect, leaving no bacteria retained in the filtrates. Attributing to SC, the PLA-based nanofibers showed extremely increased melting temperature over 200 °C and improved Young’s modulus up to 270.0 MPa. The durable nanofibers prepared in present study are meaningful for enlarging the application of PLA-based materials, for example, as filters, masks, and packages.

Nano‐Crystalline Sandwich Formed in Polylactic Acid Fibers

“…To achieve such morphology experimentally, we employed the electrospinning nanofiber forming process in a side‐by‐side (S/S) configuration where the two streams of the PLLA and PDLA solutions were brought together in parallel needles driven by precision fluid pumps. The electrospinning process has been extensively reported over the last two decades and represents a simple and versatile research tool to study material properties at the nano‐meter dimension . There have also been several studies on S/S nanofiber fabrication process, but the characteristics and application potentials of nano structures constructed through the process are only beginning to be appreciated.…”

Comparative Study of Pleurotus ostreatus Mushroom Grown on Modified PAN Nanofiber Mats

“…Other possible fields for application of nanofiber mats as filters include optical and chemical sensors, nanocatalysis, energy storage, defense, aerospace, transportation, protective clothing, air, and water filters for medical and biotechnological applications, as well as dye filters for the textile finishing industry [11,12,13,14,15,16]. Despite their advantages, there is also one big problem which limits the use of nanofiber mats as filters: the mechanical weakness of single nanofiber mat layers [9,17,18]. While this problem is usually addressed by forming composites with macroscopic textile fabrics to create mechanically stable filters, connecting multiple nanofiber mats [19], or introducing nanofiber mats into sponge-like structures [20], another possibility could be combining nanofiber mats with biological stabilizing structures.…”

Hybrid hydrogel based on stereocomplex PDLA/PLLA and gelatin for bone regeneration

“…[ 24–27 ] The desired mechanical and degradation characteristics render the PDLA/PLLA stereocomplex attractive in drug release and regenerative medicine. [ 28,29 ]…”