title: Electrospinning of poly(lactic acid) stereocomplex nanofibers.
abstract: The electrospinning of stereocomplex nanofibers of high-molecular-weight poly(L-lactic acid) (PLLA)/poly(D-lactic acid) (PDLA) (PLLA/PDLA = 1:1) was carried out with chloroform as the spinning solvent. The stereocomplex nanofibers with diameters of 830-1400 and 400-970 nm were successfully obtained at voltages of -12 and -25 kV, respectively. Wide-angle X-ray scattering indicated that with an increasing absolute value of voltage from 0 to 25 kV the crystallinity of homo-crystallites composed of either PLLA or PDLA decreased from 5% to 1%, whereas the crystallinity of stereocomplex crystallites increased slightly from 16% to 20%. The obtained results reveal that electrospinning is an effective method to prepare stereocomplex nanofibers with a negligibly small amount of homo-crystallites, even when high-molecular-weight PLLA and PDLA are used, and that the orientation caused by high voltage (or electrically induced high shearing force) during electrospinning enhances the formation and growth of stereocomplex crystallites and suppresses the formation of homo-crystallites.
authors.affiliation: Department of Ecological Engineering, Faculty of Engineering, Toyohashi University of Technology, Toyohashi, Aichi 441-8580, Japan. tsuji@eco.tut.ac.jp
authors.forename: Hideto
authors.initials: H
authors.lastname: Tsuji
authors.forename: Michihiko
authors.initials: M
authors.lastname: Nakano
authors.forename: Makoto
authors.initials: M
authors.lastname: Hashimoto
authors.forename: Kazunori
authors.initials: K
authors.lastname: Takashima
authors.forename: Shinji
authors.initials: S
authors.lastname: Katsura
authors.forename: Akira
authors.initials: A
authors.lastname: Mizuno
mesh_terms: D002152:Calorimetry, Differential Scanning / Q000379:methods; D004563:Electrochemistry / Q000379:methods; D019344:Lactic Acid / Q000138:chemical synthesis / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D008958:Models, Molecular; D008968:Molecular Conformation; D008970:Molecular Weight; D049329:Nanostructures / Q000737:chemistry*; D011091:Polyesters; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry*; D012997:Solvents
chemical_list: D011091:Polyesters; D011108:Polymers; D012997:Solvents; D019344:Lactic Acid; C033616:poly(lactide)