Advanced Materials Portfolio

Veriflex^® Shape Memory Polymer

What Are Shape Memory Polymers?

First introduced in Japan and then the United States 1984, shape memory polymers are polymers whose qualities have been altered to give them dynamic shape "memory" properties. Using thermal stimuli, shape memory polymers can exhibit a radical change from a rigid polymer to a very elastic state, then back to a rigid state again. In its elastic state, it will recover its “memory” shape if left unrestrained. However, while pliable it can be stretched, folded, or otherwise conformed to other shapes, tolerating up to 200% elongation.

While manipulated, the shape memory polymer can be cooled and therefore returned to a rigid state, maintaining its manipulated shape indefinitely. This manipulation process can be repeated many times without degradation, and CRG can tailor most polymers with shape memory properties.

What is Veriflex?

The registered trademark for CRG's family of shape memory polymer resin systems, Veriflex currently functions on thermal activation customizable from –30°C to 260°C (–20°F to 500°F). Extremely high temperatures and cryogenic ranges may be possible. CRG is also investigating possible future systems that may respond to stimuli such as light, electric field, or magnetic field. Some examples of applications include custom reusable mandrels, reusable molds, replica optics, and deployment mechanisms for outer space.

CRG has been awarded several patents based on this technology: Shape Memory Styrene Copolymers, US Pat. No. 6,759,481; Structural and Optical Application for SMP, US Pat. No. 6,986,855; Maleimide-Based High-Temp SMP, US Pat. No. 7,276,195; and Shape Memory Mandrel, US Pat. No. 7,422,714.

This coupon of Veriflex begins with a rectangular memory shape. When heated above its
transition temperature, it becomes elastic and can be manipulated into a different shape
and then cooled to maintain the new shape in a rigid state. When reheated above its
transition temperature, it will return to its memory shape if left unrestrained.

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.