Solution-Blown Poly(hydroxybutyrate) and ε-Poly-L-lysine Submicro- and Microfiber-Based Sustainable Nonwovens with Antimicrobial Activity for Single-Use Applications

Antimicrobial nonwovens for single use applications (e.g., diapers, sanitary napkins, medical gauze, etc.) are of utmost importance as the first line of defense against bacterial infections. However, the utilization of petrochemical nondegradable polymers in such nonwovens creates sustainability-related issues. Here, sustainable poly(hydroxybutyrate) (PHB) and epsilon-poly-L-lysine (epsilon-PLL) submicro- and microfiber-based antimicrobial nonwovens produced by a novel industrially scalable process, solution blowing, have been proposed. In such nonwovens, epsilon-PLL acts as an active material. In particular, it was found that most of epsilon-PLL is released within the first hour of deployment, as is desirable for the applications of interest. The submicro- and microfiber mat was tested against C. albicans and E. coli, and it was found that epsilon-PLL-releasing microfibers result in a significant reduction of bacterial colonies. It was also found that epsilon-PLL-releasing antimicrobial submicro- and microfiber nonwovens are safe for human cells in fibroblast culture. Mechanical characterization of these nonwovens revealed that, even though they are felt as soft and malleable, they possess sufficient strength, which is desirable in the end-user applications.