The recovery properties under load of a shape memory polymer composite material

Abstract

In many applications, shape memory alloys are being replaced by shape memory polymers as they have some better properties than shape memory alloys. Nevertheless, shape memory alloys can recover under load which shape memory polymers cannot. Shape memory polymers are not capable of giving full recovery even lifting a tiny load. The melting temperature or the glass transition temperature is the transition temperatures to which shape memory polymers are closely heated. Then a deforming force up to a certain position is applied to the heated shape memory polymers. After that shape memory polymer is permitted to cool while keeping it deformed. After the cooling, shape memory polymer obtains the temporary shape which can be recovered by reheating it at the similar transition temperature (glass transition or melting). Consequently, it recovers at its initial state. Shape memory polymer can achieve constrained recovery and unconstrained recovery, nonetheless; under stress, it is partly recovered. In current work, recovery under load has been investigated of an asymmetrical shape memory composite. It is established that it is capable to recover under various loads. Under various loads, it shows full recovery in reference to initial state. The ability to recover under load can be potentially used in diverse applications.

Cardiovascular Stents: A Review of Past, Current, and Emerging Devices

“…Stents from shape-memory polymers (e.g., poly(tert-butyl acrylate) and poly(ethylene glycol) dimethylacrylate) could be manufactured to preserve shape storage at ambient temperature and become fully activated at body temperature [156]. Compared to shape-memory alloys, these polymers are considered better for stent applications in terms of recoverable strain, processability, cost effectiveness, and tunability of properties [157,163]. Besides temperature-triggered transformations, light-responsive and chemically responsive shape recoveries have been investigated as alternative mechanisms to reduce tissue damage from higher heat transitions [154,[164][165][166][167].…”

Recent Progress on Electroactive Polymers: Synthesis, Properties and Applications

“…EASMPI offers a glass transition temperature of 302 • C which is higher than other EASMPs, reported in literature [133]. Before that, the maximum glass transition temperature of EAPs was reported as 150 • C or less [133,135,136]. A high glass transition temperature is helpful for EAPs because it offers them a higher threshold to transfer shape.…”

Numerical modeling of fiber reinforced polymer textile composites for characterizing the mechanical behavior – a review

“…Since alloys have specific properties of shape memory recovery while polymers are bad in shape recovery properties. Therefore, polymers were tested under different loads for the shape memory test, and it was noted that polymers were capable of recovering the shape [35].…”