Property Enhancement of Polylactide Monofilaments by Cold-Drawing Process and Solvent Infusion
Jirawan Jindakaew, Chalita Ratanatawanate, Takeshi Kikutani, and Pakorn Opaprakasit** Author for corresponding; e-mail address: pakorn@siit.tu.ac.th
Volume: Vol.48 No.2 (March 2021)
Research Article
DOI:
Received: 18 September 2020, Revised: -, Accepted: 27 January 2021, Published: -
Citation: Jindakaew J., Ratanatawanate C., Kikutani T. and Opaprakasit P., Property Enhancement of Polylactide Monofilaments by Cold-Drawing Process and Solvent Infusion, Chiang Mai Journal of Science, 2021; 48(2): 323-331.
Abstract
Post treatments of polymeric products after fabrication, especially improvements of their crystallinity, are commonly applied to further enhance properties of the materials. In this study, a cold-drawing process in various environments is developed for poly(L-lactide) (PLLA) monofilaments, whose solvent-infusion mechanism is examined. Multiple necking behavior was observed when the filaments were drawn in water and ethanol, compared to a single-neck deformation when the experiment was conducted in air. The number of necks was also dependent on the drawing media conditions, in which the number of necks decreased with an increase in the draw ratio (DR). The number of necks of the filaments drawn in water and ethanol increased with a further increase in the drawing speed. The drawing treatments in ethanol lead to a decrease in the yield and drawing stresses. and an increase in the natural draw ratio (NDR) of the monofilaments. The results also indicate that ethanol is effectively infused into the PLLA filaments, leading to further chain arrangements. The process has high potential for promoting the crystallization of filaments in cold drawing conditions, leading to enhancement in the mechanical properties.