Biocidal Agent for Modification of Poly(lactic acid) High-efficiency Filtering Nonwovens

Abstract

*Laboratory of Microbiocides Chemistry, Faculty of Chemistry, Adam Mickiewicz University, Umultowska 89b, Poznan 61-614, Poland e-mail: brycki@amu.edu.pl Abstract The article presents research on the development of modified poly(lactic acid) (PLA) melt-blown nonwovens for construction of respiratory protection devices (RPD) against biological hazards. Due to this specific application of nonwovens, a new biocidal agent was developed which fulfils two basic criteria. The first one is the efficient destruction of microorganisms harmful for people, and the second is no negative influence on compost activity in the process of BIO-nonwoven biodegradation. The biocidal agent was composed of biologically active chemical compounds, which were permanently imbued into the perlite matrix. The modified poly(lactic acid) (PLA) melt-blown nonwovens were tested for basic filtering parameters with the use of standard model aerosols as well as bioaerosols. A microbiological study was performed to prove the antimicrobial activity of the modified nonwovens against Gram-positive and Gram-negative bacteria. It was shown that modified PLA at low concentrations did not eliminate microorganisms that dwell in organic compost, and that the time of BIO-nonwoven biodegradation was 56 days. Survival of microorganisms after 2 hours of contact with the BIO-nonwoven was zero %, which means that the nonwovens tested were characterised by activity at the highest level, 3rd,, towards Gram-positive and Gram-negative bacteria. At the same time, the effectiveness of the BIOnonwovens towards model aerosols (sodium chloride and mist of paraffin oil) was at a level that would ensure obtaining a 2nd class of protection of the filtering RPD.