What is shape memory polymer affected by?
Because shape memory polymers can respond to temperature, light, pH and moisture, there are many very interesting possibilities for these materials in fabrics. These include comfort, aesthetics, wound monitoring, protection against environmental conditions, smart controlled drug release, and more.
What is shape memory polymer used for?
Importance of Shape Memory Polymers Some examples, where these materials have been used are in implantable biomedical devices, preparation of electroconductive and magnetic composite materials, in textile applications and in the preparation of coatings for metal corrosion, among others.
What special property does a shape memory polymer have?
Shape-memory polymers are an emerging class of active polymers that have dual-shape capability. They can change their shape in a predefined way from shape A to shape B when exposed to an appropriate stimulus.
How does shape memory work?
When a shape memory alloy is in its martensitic form, it is easily deformed to a new shape. However, when the alloy is heated through its transformation temperatures, it reverts to austenite and recovers its previous shape with great force. This process is known as shape memory.
What is shape memory effect explain with example?
Shape memory effect (SME) is a phenomenon, in which a material recovers to its original size and shape when heated above a certain characteristic transformation temperature. From: Characterization of Biomaterials, 2013.
What are the different types of shape-memory effect?
The two-way shape-memory effect is the effect that the material remembers two different shapes: one at low temperatures, and one at the high temperature. A material that shows a shape-memory effect during both heating and cooling is said to have two-way shape memory.
What causes shape memory?
What are shape memory polymers examples?
These polymers have been used to produce, among other things, medical devices such as stents and catheters. Typical examples of polymers which can exhibit this shape memory effect include (meth)acrylates, polyurethanes, and blends of polyurethane and polyvinylchloride.
What are the properties of shape-memory alloys?
Shape memory alloys are a unique class of alloys that have ability to ‘remember’ their shape and are able to return to that shape even after being bent. At a low temperature, a SMA can be seemingly plastically deformed, but this ‘plastic’ strain can be recovered by increasing the temperature.
What is the most common shape memory polymer?
Thermoplastic shape-memory While shape-memory effects are traditionally limited to thermosetting plastics, some thermoplastic polymers, most notably PEEK, can be used as well.
How does the shape memory effect work?
„Shape Memory“ describes the effect of restoring the original shape of a plastically deformed sample by heating it. This phenomenon results from a crystalline phase change known as „thermoelastic martensitic transformation“. At temperatures below the transformation temperature, shape memory alloys are martensitic.
What are shape-memory polymers?
Shape-Memory Polymers (SMPs) are considered a kind of smart material able to modify size, shape, stiffness and strain in response to different external (heat, electric and magnetic field, water or light) stimuli including the physiologic ones such as pH, body temperature and ions concentration.
Does shape memory exist in polymer networks intended for biomedical applications?
We examine the shape memory effect in polymer networks intended for biomedical, and specifically cardiovascular, applications. The polymers were synthesized by photopolymerization from a tert-butyl acrylate monomer with a diethyleneglycol diacrylate crosslinker.
What are chemically induced shape memory polymers (SMPs)?
Shape memory polymers induced by chemical triggers such as pH, water, solvents or biological agents are classified as chemically induced SMPs. Physiological human body pH varies depending on human body area and on pathological conditions. Therefore, pH-sensitive SMPs find an interesting application in the biomedical field [ 42 ].
What is shape memory material?
Shape memory materials are immensely useful because of their capability to recover their original shapes upon exposure to an external stimulus such as heat, moisture, light or a magnetic field. This book reviews key recent research in shape memory polymers, their properties and applications.