文献类型：期刊文献

英文题名：Molecular Dynamics Study on the Stress Concentration in Polymer Networks with Dangling Chains

作者：Wang, Xuan[1,2];Zhao, Shuangliang[1,2,3,4];Xu, Xiaofei[1,2]

机构：[1]East China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Sch Chem Engn, Shanghai 200237, Peoples R China;[3]Guangxi Univ, Guangxi Key Lab Petrochem Resource Proc & Proc Int, Nanning 530004, Peoples R China;[4]Guangxi Univ, Sch Chem & Chem Engn, Nanning 530004, Peoples R China

年份：2024

卷号：128

期号：18

起止页码：4544

外文期刊名：JOURNAL OF PHYSICAL CHEMISTRY B

收录：;EI(收录号：20241816019967);WOS:【SCI-EXPANDED(收录号:WOS:001226287000001)】；

基金：This work is supported by the National Natural Science Foundation of China (nos. 21978079 and 22178072).

语种：英文

外文关键词：Coarse-grained modeling - Defects - Graph theory - Molecular dynamics

摘要：Owing to structural defects, stress concentration frequently occurs in polymer network materials (PEMs), significantly altering their overall mechanical properties. Here, we investigate the impact of dangling chain defects on the stress concentration in PEMs using coarse-grained molecular dynamics simulation. Stress distributions on the network structure are calculated by using graph theory, with considering the effects of defect ratio (phi) and the distance from defects. It is found that the existence of dangling chains can alleviate stress by dissipating more internal energy. When considering the effects of all defects statistically, the stress concentration consistently occurs near the joint segments between dangling chains and the bare network (i.e., removing all of the dangling chains from the network). The stress concentration effect is significant when defects are in the region near the network edges. Stress tends to concentrate more on the dangling chains at low phi, while it tends to concentrate more on the bare network at high phi because of the enhanced chain motions in bare network. This implies that the stress concentration effect near the joint segment is predominant at low phi, and it is slightly weak as phi increased.