Shape Memory Polymers - An Overview
(See Veriflex®)
What is Shape Memory Polymer?
Page 1
Shape memory polymer (SMP) has
only been around for a couple of decades. It has applications
from deploying objects in space to manufacturing dynamic molds.
Unlike shape memory alloys, SMP
exhibits a radical change from a normal rigid polymer to a
very stretchy elastic and back on command, a change which
can be repeated without degradation of the material. The "memory,"
or recovery, quality comes from the stored mechanical energy
attained during the reconfiguration and cooling of the material.
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Above its transition temperature, SMP goes
from a rigid, plastic state to a flexible, elastic state.
When cooled, it becomes rigid again and can be constrained
in its new shape configuration. Shape memory characteristics
can be engineered into most polymers. Some of CRG's current
SMP formulations are based on styrene acrylate, cyanate ester,
and epoxy polymer systems.
There are many activation methods for thermally responsive SMP:
Resistive heating
Embedded heaters (for example, stretchy heaters, nichrome wires)
Contact heating (MRE heaters)
Induction heating
Dielectic heating
Microwave heating
Infrared radiant heating
Some of these methods may be enabled by fillers such as conductive fillers, CNT, CNF, iron and ferrite.
