マグネタイト/PLAナノファイバーの機械的特性評価

抄録

Hyperthermia has been reported to be an effective cancer treatment, and magnetic nanofibers are expected to be used for it. As a material of the nanofiber for this purpose, poly lactic acid (PLA) and magnetite (Fe₃O₄) are used. Aligned fabrics and nonwoven fabrics are usually used for evaluation of mechanical properties on nanofibers containing nano-particles. Since their detailed fracture mechanisms have not been clarified yet, mechanical properties of single nanofiber which is the element of these aligned and nonwoven fabrics must be evaluated. In this study, PLA single nanofibers, magnetite/PLA single nanofibers and their aligned and nonwoven fabrics were fabricated by the electrospinning method and their mechanical properties were evaluated by tensile test. Aligned fabrics having the largest distribution of orientation angle from 80° to 90° can be fabricated by the rotation speed of the drum collector at more than 2000 rpm. By applying oleic acid treatment to the magnetite, which is added to the PLA nanofiber, the formation of clusters and the decrease of tensile strength of the PLA nanofibers is suppressed. In the nonwoven fabric, not only the tensile strength of the single nanofiber but also the bond at the intersection of their nanofibers greatly affects the tensile strength.