A coupling model for cooperative dynamics in shape memory polymer undergoing multiple glass transitions and complex stress relaxations

POLYMER

卷:181

Article

Wang, Xiaodong¹  Liu, Yuheng¹  Lu, Haibao¹  Wu, Nan²  Hui, David³  Fu, Yong-Qing⁴ 

[1] Harbin Inst Technol, Sci & Technol Adv Composites Special Environm Lab, Harbin 150080, Heilongjiang, Peoples R China

[2] Univ Manitoba, Dept Mech Engn, Winnipeg, MB R3T 2N2, Canada

[3] Univ New Orleans, Dept Mech Engn, Composite Mat Res Lab, New Orleans, LA 70148 USA

[4] Northumbria Univ, Fac Engn & Environm, Newcastle Upon Tyne NE1 8ST, Tyne & Wear, England

关键词: Shape memory polymer;    Shape memory effect;    Cooperative dynamics;   

DOI  :  10.1016/j.polymer.2019.121785

来源: Elsevier

【 摘 要 】

Modelling multi-shape memory effect (multi-SME) of shape memory polymers (SMPs) is a critical challenge for fields of mathematics/statistics and condensed-matter physics. These SMPs have a huge number of segments and their thermomechanical behaviors are determined by heating history and cooperative relaxations (e.g., relaxation of all segments occurs simultaneously). In this study, a one-dimensional coupling model was proposed to investigate the cooperative dynamics of multiple glass transitions and thermomechanical behaviors of the SMPs. The overall relaxation behaviors of different tangled segments in the SMPs were formulated based on the Boltzmann's superposition principle by coupling the highest transition temperature (T-min) and initial transition temperature (T-max) of all segments. Dependences of thermomechanical properties and relaxation strains upon the parameters of T-max, T-min, relaxation time and heating rate were theoretically investigated. Multiple glass transitions, thermomechanical and shape memory behaviors of the SMPs have been well described using this newly proposed coupling model. Finally, the simulation results were compared with the experimental data, and good agreements between them were obtained.

【 授权许可】

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