Context: 

Researchers from the Indian Institute of Science (Departments of Materials Engineering and Bioengineering) have successfully applied 4D printing techniques to create artificial blood vessels.

More on the news

• These artificial blood vessels could be used as grafts (replacements) for blocked, injured, or damaged blood vessels.
• Current grafts require additional surgeries, which carry risks of rejection and disease transmission and are prone to clotting and other complications. These artificial blood vessels are a step forward in solving these challenges.
• The  researchers have developed a specially formulated nanoengineered hydrogel ink that isused to print the blood vessels into sheets. About the 4D Printing Skylar Tibbits, an assistant professor from the Massachusetts Institute of Technology (MIT), introduced the idea of “4D printing” in 2013.
• 4D Printing is referred to as 3D printing transformed over time. 
• It involves creating self-assembling, programmable materials that are designed to change shape over time, functioning like a form of active origami. 
• The term '4D' refers to the incorporation of time as an additional dimension, highlighting how the printed object transforms over time.
• The difference is that the 4D Printing technology uses programmable and advanced materials that perform a different functionality by adding hot water, light or heat. That’s why a non-living object can change its 3D shape and behaviour over time. 

What is 3D Printing? 

3D printing or additive manufacturing is a process of making three dimensional objects from a digital file.

The creation of a 3D-printed object is achieved using additive processes. In an additive process an object is created by laying down successive layers of material until the object is created. 

How does 4D printing work?

4D printing technology uses commercial 3D printers, such as Polyjet 3D printers. 

The input is a “smart material”, that can be either a hydrogel or a shape memory polymer.

4D Printing Applications

• By adapting the shape-shifting behaviour available in 4D, more complicated electronic components can be developed.
• Aerospace, automotive, clothing, construction, military, healthcare and manufacturing are the forefront industries that can explore the 4D Printing.