Shape memory polymers (SMPs)
Publishing Time:2023-08-10

Shape memory polymers (SMPs)

Shape memory polymers (SMPs) are a kind of stimuli-responsive smart materials with the ability to undergo a large recoverable deformation upon certain external stimulus, (e.g., heat, electricity, light, magnetism, moisture and chemicals). SMPs possess numerous technical advantages compared with shape memory alloys including high recoverable strains, ease of processing, the ability to tailor the recovery temperature, programmable and controllable recovery behavior, low cost and light-weight, etc. Combining such advantages with the smart shape memory behavior, SMPs presents significant potential and practical applications in various important fields.


Fig. 1 Schematic of shape memory effect during a typical thermo-mechanical cycle


In our group, we focus on:

(a)  Fabrication of various kinds of SMPs with different glass transition temperatures (Tg), including

Table1. Types of Shape Memory Polymers

Thermosetting SMPs

Tg (℃)

thermoplastic  SMPs

Tg (℃)

Polyimide

Cynate

Styrene

Epoxy

Bismaleimide

90-320

160-250

47-88

100-188

95-123

Poly (ε-caprolactone)

Polyurethane

Poly(arylene ether ketone)s

Chitosa

37-46

27-45

116-140



61-63

 

We can provide diverse SMPs with different Tg for future collaborations.

(b) Investigation of the actuation approaches of SMPs and their composites, including:

· Thermal-actuated method

· Electrical-actuated method

· Light-actuated method

· Magnetic-actuated method

· Solvent-actuated method

· Multistage-actuated method

 

Fig. 2 Thermal-actuated SMPs shape recovery process in 60 ℃ water

Fig. 3 Electrical-actuated SMPs shape recovery process at 30 V

Fig. 4 Light-actuated SMPs. (a) Wavelength-selective shape memory structures based on PAEK/CA, PAEK, and PAEK-ABZ components; (b) Smart man and (c) Flower with their diverse customized actions

Fig. 5 Magnetic-actuated SMP. (a) Real process;(b)Shape recovery behavior of 4D printed structures with 15% Fe3O4 at 27.5kHz

Fig. 6 Solvent-actuated SMPs with 3D microvoid is designed based on chemical interaction

Fig. 7 Multistage-actuated SMPs.(a) in 34℃, 37℃ and 41℃ temperature, respectively; (b) in an alternating magnetic field with a frequency of 20 kHz and a field strength of 6.8 kA m-1 and (c) in the supplied voltage 60 V

 

(c) Exploration of the potential and practical applications of SMPs and their composites in various fields, including:

· Deployable structures

· Morphing structures

· Medical devices

· Foams

· Smart mandrel

· Self-healing systems