A comprehensive review on thermomechanical constitutive models for shape memory polymers

Abstract

Shape memory polymers are a class of smart materials, which are capable of fixing their deformed shapes, and can return to their original shape in reaction to external stimulus such as heat. Also due to their exceptional properties, they are mostly used in four-dimensional printing applications. To model and investigate thermomechanical response of shape memory polymers mathematically, several constitutive equations have been developed over the past two decades. The purpose of this research is to provide an up-to-date review on structures, classifications, applications of shape memory polymers, and constitutive equations of thermally responsive shape memory polymers and their composites. First, a comprehensive review on the properties, structure, and classifications of shape memory polymers is conducted. Then, the proposed models in the literature are presented and discussed, which, particularly, are focused on the phase transition and thermo-viscoelastic approaches for conventional, two-way as well as multi-shape memory polymers. Then, a statistical analysis on constitutive relations of thermally activated shape memory polymers is carried out. Finally, we present a summary and give some concluding remarks, which could be helpful in selection of a suitable shape memory polymer constitutive model under a typical application.

Experimental and computational analysis of a pharmaceutical-grade shape memory polymer applied to the development of gastroretentive drug delivery systems

“…To date, several constitutive models have been proposed for the analysis and simulation of the shape memory effect of different polymers (see (Yarali 2020)), including thermo-viscoelastic (Tobushi 1997, Lin 1999, Morshedian 2005, Nguyen 2008, Srivastava 2010) and phase transition , Chen 2008, Wang 2009, Reese 2010, Boatti 2016 approaches.…”

Constitutive Modeling of multi-stimuli-responsive shape memory polymers with multi-functional capabilities

“…Compared with shape memory alloys, SMPs possess the advantages of high strain recovery (up to 1000% [14]), low density, low cost, biocompatibility and easy shape-programming process [15]. SMPs due to their Shape Memory Effect (SME) and self-healing property are designed into actuators or sensors offering outstanding advantages and extensively utilized in various fields such as aerospace, biomedical, civil engineering, and 3D (or 4D) printing [16][17][18][19][20][21][22].…”

“…Besides, heat can be generated in direct and indirect ways (e.g., inducing heat remotely). Considering the open literature, there are a lot of constitutive models for thermally-induced SMPs under small and large strains [22]. For other types of SMPs (e.g., electro-magneto-responsive SMPs), however, there is only one model for electro-responsive SMPs [23].…”

“…In recent years, a world-wide activity has been devoted to simulating behaviors of SMPs and EMREs. More details in constitutive modeling SMPs and EMREs can be found in research works done by Yarali et al [22] and Rossi et al [29]. As the understanding of SMP properties is getting deeper and deeper in material research community, the list of applications continues to expand.…”

Corrigendum to “Magnetorheological elastomer composites: Modeling and dynamic finite element analysis” [Compos. Struct. 254 (2020) 112881]

“…The advanced composite materials can be fabricated from smart materials such as shape memory alloys (SMAs), shape memory polymers (SMPs), piezoelectrics, magneto-electro-elastics (MEE), electrorheological (ER) and magnetorheological (MR) materials. Using these materials can provide additional functionalities to the composites, such as shape memory effect, reversible cyclic behavior, and mag-netic or electric dependent behavior [8][9][10][11][12][13][14]67]. Among these smart materials, MR elastomers (MREs), which are polymers reinforced by ferromagnetic particles [15], have recently gained a great deal of attention due to their sensitivity to the magnetic fields [16].…”