TY - JOUR

T1 - The micro response mechanisms of foamed polymer rehabilitation material under compression

T2 - From a closed cell view

AU - Wu, Yongshen

AU - Zhang, Chao

AU - Wang, Cuixia

AU - Rabczuk, Timon

AU - Zhu, Pengjia

AU - Zhao, Peng

AU - Wang, Lei

AU - Zhuang, Xiaoying

AU - Zhang, Juan

AU - Fang, Hongyuan

N1 - Funding Information: This research was supported by the National Natural Science Foundation of China (No. 52178368 , 51978630 , 51909242 , 52009125 ), the Program for Science and Technology Innovation Teams and Talents in Universities of Henan Province (No. 23IRTSTHN004 and 23HASTIT007 ), the Guangdong Innovative and Entrepreneurial Research Team Program ( 2016ZT06N340 ), the Program for Guangdong Introducing Innovative and Entrepreneurial Teams (NO. HG-GCKY-01-002 ), the China Postdoctoral Science Foundation (No. 2020TQ0285 , 2022M722882 ), Key Project of Natural Science of Henan Province ( 232300421137 ), Central Plains Talent Program - Top Talents of Central Plains Youth, Research Preferential Foundation for Selected Overseas Chinese of Henan Province, the First-class Project Special Funding of Yellow River Laboratory ( YRL22LT07 ), and Key scientific research projects of colleges and universities in Henan Province (No. 21A570007 ), for which the authors are grateful acknowledged.

PY - 2023/7

Y1 - 2023/7

N2 - 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.

AB - 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.

KW - Deformation mechanisms

KW - Micromechanical properties

KW - Molecular dynamics

KW - Polyurethane cell

UR - http://www.scopus.com/inward/record.url?scp=85162760178&partnerID=8YFLogxK

U2 - 10.1016/j.polymertesting.2023.108082

DO - 10.1016/j.polymertesting.2023.108082

M3 - Article

AN - SCOPUS:85162760178

VL - 124

JO - Polymer testing

JF - Polymer testing

SN - 0142-9418

M1 - 108082

ER -