Characterization of structure and properties of polylactic fiber

Abstract

Polylactic fiber (PLA) is a new environment-friendly fiber and has been produced by different plants with wide application, while there are few studies on the difference of the structure and property of PLA fibers produced from these plants in China. The main content in present article is to conduct elementary analysis, gas chromatography mass spectrum, IR spectroscopy, ultraviolet, X-ray, differential scanning calorimetry (DSC), TG, SEM, and tensile tests to obtain the common structure and properties of PLA fibers and to prove that there are no significant difference between the 13 kinds of PLA fibers made by 13 plants in China. The elementary analysis method is used to test the contents of C, H, and O elements, and it has good accordance with the theoretical results. Gas chromatography mass spectrum method proves that the functional groups of PLA fiber are lactide and acetaldehyde as well as 2,3-pentanedione. IR spectroscopy depicts that significant absorbing peaks exist as -C=O-, -C-O-, -OH- within absorbing wavelength zones. There are no characteristic absorbing peaks of ultraviolet spectrum. Crystallinity and orientation degree in full wave at half maximum and in area are calculated based on X-ray. The peak melting point and pyrogenation peak point are obtained by DSC and TG testings. The tensile property and the surface morphology by SEM are conducted and some typical faults in the surface are observed. In addition, the coefficient of variance of these experimental results between 13 kinds of PLA fibers show that their structure and properties are similar. © 2012 Wiley Periodicals, Inc.