The micro response mechanisms of foamed polymer rehabilitation material under compression

From a closed cell view

authored by

Yongshen Wu, Chao Zhang, Cuixia Wang, Timon Rabczuk, Pengjia Zhu, Peng Zhao, Lei Wang, Xiaoying Zhuang, Juan Zhang, Hongyuan Fang

Abstract

Non-aqueous reactive foamed polyurethanes are widely used in the non-excavation rehabilitation of infrastructures and fundamental engineering. However, the effect of a microscopic cell on the understanding of micro-mechanical properties of a polyurethane is not clearly stated. In this work, a molecular model of a polyurethane closed cell is established corresponding to the field emission scanning electron microscopy results. Molecular dynamics simulations were subsequently employed to investigate the effect of a closed cell on the micro-mechanical response of polyurethane during compression. Based on the layered non-affine displacement and internal structure variables, we find that the existence of cells reduces changes in the polymer chain structure, i.e., the bond stretching, bond angle bending, and dihedral angle rotation. This makes slippage of the polymer chain more violent, and the farther away from the centre of the cell, the greater the level of the polymer chain slippage. In other words, chain slippage plays a key role in reducing the mechanical properties of a polymer. What’ s more, it is found that the number of hydrogen bonds in the cell is significantly less than that in the elastomer, which also could reduce the mechanical properties of foamed polyurethane. This study provides an efficient route for studying the micro-mechanical characterization of foamed polyurethane.

Organisation(s)

PhoenixD: Photonics, Optics, and Engineering - Innovation Across Disciplines

External Organisation(s)

Zhengzhou University
National Local Joint Engineering Laboratory of Major Infrastructure Testing and Rehabilitation Technology
Collaborative Innovation Center for disaster prevention and control of Underground Engineering
Bauhaus-Universität Weimar
China Railway Seventh Group Ltd.
Southern Institute of Infrastructure Testing and Rehabilitation Technology
Wanhua Energysav Science & Technology Group Co. Ltd.
China Communications Construction Group Co. Ltd.

Type

Article

Journal

Polymer testing

Volume

124

ISSN

0142-9418

Publication date

07.2023

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Polymers and Plastics, Organic Chemistry

Electronic version(s)

https://doi.org/10.1016/j.polymertesting.2023.108082 (Access: Open)