Melting Temperature of Individual Electrospun Poly(vinylidene fluoride) Fibers Studied by AFM-based Local Thermal Analys

  • PDF / 1,319,425 Bytes
  • 9 Pages / 595.35 x 842 pts (A4) Page_size
  • 37 Downloads / 189 Views

DOWNLOAD

REPORT


ARTICLE 

POLYMER SCIENCE    

https://doi.org/10.1007/s10118-020-2476-9 Chinese J. Polym. Sci.

Melting Temperature of Individual Electrospun Poly(vinylidene fluoride) Fibers Studied by AFM-based Local Thermal Analysis Ze-Qian Wanga,b, Zhen-Xing Zhonga,b, Yu-Ying Mac, Xiao-Feng Luc, Ce Wangc, and Zhao-Hui Sua,b* a State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China b University of Science and Technology of China, Hefei 230026, China c Alan G. MacDiarmid Institute, Jilin University, Changchun 130012, China

 Electronic Supplementary Information Abstract   Thermal properties such as melting temperature can well reflect the microstructure of the polymer material, and have practical implications in the application of nanofibers. In this work, we investigated the melting temperature of individual electrospun poly(vinylidene fluoride) (PVDF) nanofibers with diameters ranging from smaller than 200 nm to greater than 2 μm by the local thermal analysis technique. The PVDF fibers obtained under four different conditions were found to crystallize into α and β phases, and the fiber mats showed typical values in the crystallinity and Tm with no significant difference among the four. However, analyses at single fiber level revealed broad distribution in diameter and Tm for the fibers produced under identical electrospinning condition. The Tm of individual nanofibers was found to remain constant at large diameters and increase quickly when reducing the fiber diameter toward the nanoscale, and Tm values of 220−230 °C were observed for the thinnest nanofibers, much higher than the typical values reported for bulk PVDF. The Tm and molecular orientation at different positions along a beaded fiber were analyzed, showing a similar distribution pattern with a minimum at the bead center and higher values when moving toward both directions. The results indicate that molecular orientation is the driving mechanism for the observed correlation between the Tm and the diameter of the nanofibers. Keywords   Electrospun fibers; PVDF; Local thermal analysis; Melting temperature Citation: Wang, Z. Q.; Zhong, Z. X.; Ma, Y. Y.; Lu, X. F.; Wang, C.; Su, Z. H. Melting temperature of individual electrospun poly(vinylidene fluoride) fibers studied by AFM-based local thermal analysis. Chinese J. Polym. Sci. https://doi.org/10.1007/s10118-020-2476-9

 

INTRODUCTION Electrospinning is a versatile and facile technique for manufacturing polymeric nanofibers with diameters ranging from several tens of nanometers to micrometers,[1] and electrospun fibers have found application in a broad range of fields, such as catalysis, filtration,[2−4] drug delivery,[5,6] and tissue engineering.[7−9] It is well known that the electrospinning process condition can affect the structure, which in turn results in different mechanical properties of the fibers. In particular it has been reported extensively that electrospun nanofibers would exhibit a significant increase in the mo

Data Loading...