Comparison of morphological, structural and antibacterial properties of different Apocynum venetum poly (lactic acid)/nanocellulose nanofiber films

Abstract

As new bio-based sustainable materials, this paper made a comparative study on the phloem and straw of Apocynum venetum. The cellulose nanofibers (CNFs) of Apocynum venetum phloem and straw were prepared by the acid hydrolysis method, and then different parts and proportions of poly (lactic acid) (PLA)/CNF films were prepared via electrospinning, respectively. The results revealed the CNF with longer length and finer diameter network structure can be separated by straw, while the short nanostructure of the rod-like structure can be separated by phloem. It was also shown that the wettability and permeability of PLA improved significantly by adding these two kinds of CNFs, the water contact angle of PLA decreased from 130° to 101° and the permeability was up to 4658 g/(m2•d). As for antibacterial properties, the antibacterial rate of CNF from straw proved slightly better than that from phloem against E.coli, reaching more than 90%. It proved that the CNF from straw showed excellent performance as phloem, providing a novel material for the preparation of CNFs, which can be naturally antibacterial and environment-friendly. The obtained PLA/CNF films could be potentially applied in antibacterial medical dressings.