China Plastics ›› 2024, Vol. 38 ›› Issue (4): 1-5.DOI: 10.19491/j.issn.1001-9278.2024.04.001

• Materials and Properties •    

Study on 3D phase structure in low density polyethylene/ethylene⁃vinyl alcohol copolymer (PE⁃LD/EVOH) blends through confocal Raman imaging

ZHANG Chunbo(), LIU Xuanbo(), YAO Xuerong, SU Cui, SHI Hongwei, ZHANG Longgui, ZHANG Taoyi   

  1. SINOPEC (Beijing) Research Institute of Chemical Industry Co,Ltd,Beijing 100013,China
  • Received:2023-09-13 Online:2024-04-26 Published:2024-04-22

Abstract:

The phase structure of polymer blends directly affects the macroscopic properties of the materials; therefore, it is important to investigate the size and spatial distribution of each phase. In this work, the confocal Raman imaging technique was adopted to study the distribution of phases of PE⁃LD/EVOH blends in the horizontal and depth directions and 3D space in the compression⁃molded specimens. The phase structure of PE⁃LD/EVOH blends in 3D space was obtained at the first time, and the phase region visually corresponded to the chemical composition of the blends. The results indicated that the PE⁃LD/EVOH blends were immiscible system. 20 wt% EVOH could be dispersed in the PE⁃LD matrix in a regular cylindrical form with a diameter of the cylinder in the range of 3~6 μm. The introduction of polyethylene grafted with maleic anhydride (PE⁃g⁃MAH) made the phase structure change significantly from the regular to irregular shape, and the cross⁃section size was reduced to 2 μm. This indicates that PE⁃g⁃MAH can enhance the compatibility between PE⁃LD and EVOH significantly.

Key words: Raman imaging, low?density polyethylene, ethylene?vinyl alcohol copolymer, blend, 3D phase structure

CLC Number: