Shape Memory Polymers
Shape memory polymers are smart material that as result of external stimulus can change from a temporary deformed shape back to original shape. Shape memory polymers have the capability of changing their shape in response to external stimulus. One of these external stimuli is temperature. Thermo responsive shape memory polymer consist of two polymer component and resulting into two phases one with higher melting temperature than other. Shape memory effect is not related to specific material property of single polymer, but instead of is realized from combination of polymer structure and polymer morphologies.
The shape memory behavior can be produced with appropriate structure and morphologies combination with significantly different chemical composition. The shape memory polymer system after processing into a permanent form which can be deformed to produced another shape. First the polymer system is conventionally processed to receive its permanent shape , deforming the polymer system to its temporary shape is called programming which could include cold drawing, deforming , and or heating. A permanent shape can therefore be stored in the system while it takes the induce the temporary shape
The phases corresponding to higher melting polymer component acts as the physical cross- links responsible for a permanent shape. The second component acts as a molecular switch and helps to freeze temporary shape below the transition temperate or molecular temperature serving as transition or switching temperature.
Designs of shape memory polymer are advanced to the level that it is possible to design and produce specific combination of properties required. The specific application by slightly varying the chemical composition the system. Some of the shape memory polymers are biocompatible or biodegradable. Currently the main applications of shape memory polymer are in the medical field. However, since shape memory polymers are not expensive to produce, their application could be easily advanced to other areas to take advantages of their unique properties. It can have various uses in industries such as auto chokes in engine. In robotics it uses for smooth gripping foams of robots. In defense it can be used for the production of aircraft which morph during flight and a suit adjustable for every season. Hence one can hope more researches and developments in field of shape memory polymer serving for the welfare of mankind
About the Author
The Authors are students of Govt.Poly.Nagpur
This paper was also presented at event under national level grand fiesta PRAGYAA-2010 Department of Textile Technology of S G G S I E &T., Nanded.
