The ability of the Coincidence Doppler Broadening Spectroscopy to characterize polymers containing different chemical elements

J Yang; T Zhang; L A Han; X Z Cao; R S Yu; B Y Wang

doi:10.1016/j.saa.2017.01.028

The ability of the Coincidence Doppler Broadening Spectroscopy to characterize polymers containing different chemical elements

Spectrochim Acta A Mol Biomol Spectrosc. 2017 Apr 15:177:97-103. doi: 10.1016/j.saa.2017.01.028. Epub 2017 Jan 17.

Authors

J Yang¹, T Zhang², L A Han², X Z Cao³, R S Yu³, B Y Wang³

Affiliations

¹ Department of Applied Physics, Xi'an University of Sciences and Technology, Xi'an 710054, China. Electronic address: yangjing10@xust.edu.cn.
² Department of Applied Physics, Xi'an University of Sciences and Technology, Xi'an 710054, China.
³ Institute of High Energy Physics, Chinese Academy of Sciences, No. 19 Yuquan Lu, Beijing 100049, China.

PMID: 28131018
DOI: 10.1016/j.saa.2017.01.028

Abstract

Hydrocarbon polymers, O-containing, F-containing and Cl-containing polymers are comprehensively studied by Coincidence Doppler Broadening Spectroscopy (CDBS). It is shown that for polymers with different chemical structure, CDBS results can effectively distinguish polar groups CO, CCl, and CF. For polymers with similar chemical structure, the intensity of the element-specific peak in the CDBS ratio curve is dependent not only on the fraction of free positrons, but also on the content of characteristic atom in polymer repeated unit, and the polarity of the polymer molecule. For polymers containing several different polar groups, such as PCTFE (CF & CCl) and PFA (CF & CO), whether the element-specific peak appears or not depends on the amount of the polar groups and its positron capture ability. This work may provide insights into potential applications of CDBS for studying complex polymer systems.

Keywords: Polar groups; Polymer; Positron annihilation.