Fabrication of Aligned Poly(L-lactide) Fibers by Electrospinning and Drawing

• Published in: Macromolecular materials and engineering Vol. 294; no. 10; pp. 658 - 665
• Main Authors: Afifi, Amalina M., Nakajima, Hajime, Yamane, Hideki, Kimura, Yoshiharu, Nakano, Shigeyuki
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 12.10.2009; WILEY‐VCH Verlag; Wiley
• Subjects: Accumulators; aligned fibers; Alignment; Applied sciences; Collectors; Electric potential; Electrospinning; Exact sciences and technology; Fibers; Machinery and processing; molecular orientation; Plastics; poly(L-lactide); Polymer industry, paints, wood; Spinning; Technology of polymers; Voltage; aligned fibers; Crystal orientation; Optically active polymer; Synthetic fiber; Electrospinning; Mechanical properties; Nanofiber; Experimental study; molecular orientation; Lactic acid polymer; Hot drawing; Oriented polymer; poly(L-lactide); Morphology; drawing; Fiber orientation; Manufacturing
• ISSN: 1438-7492; 1439-2054
• DOI: 10.1002/mame.200900101

A new target collector was designed for taking up aligned nanofibers by electrospinning. The collector consists of a rotor around which several fins were attached for winding electrospun filaments continuously in large amounts. The alignment of the nanofibers wound on the collector was affected by the electrospinning conditions, such as the needle‐to‐collector distance and the applied voltage, but not by the rotation speed of the collector. At a voltage of 0.5 kV · cm−1, about 60% of the fibers were found to be aligned within an angle of ± 5° relative to the rotational direction of the collector. The fiber alignment was improved to 90% by drawing the fiber bundle 2–3 times at 110 °C. The drawing was also effective for crystal orientation of the fibers as revealed by WAXD. The drawn fibers show improved mechanical properties. Well‐aligned electrospun fibers of poly(L‐lactide) were successfully obtained using a newly designed rotating collector (shown). The aligned electrospun fibers were subjected to cold‐ drawing by conventional drawing method. Orientation‐induced crystallization and crystal orientation was observed from wide‐angle X‐ray diffraction pattern and thermal analysis. Tensile properties were also observed to increase with drawing of the aligned PLLA electrospun fibers.