Published on March 29th, 2017 | by Geetika Bhasin
Dartmouth researchers build super-strong cube using 3D printing techniques
Researchers at the Dartmouth College under the guidance of Dr Chenfeng Ke have designed a resilient and smart material. They have used Roxatanes to 3D print this super strong material. These roxatanes are dumbbell-shaped molecules that convert input energy into molecular movements. Since these nanoparticles move in response to external stimuli, they are also called nanomachines.
The researchers 3D printed a nanoscale cube that is capable of lifting objects 15 times their own weight. Dr. Ke wanted to build a polymer using billions of molecules that could be bonded together in the form of a string, with the help of water. The only issue in making roxatanes work is that since the nanomachines are randomly oriented they tend to cancel out each other. They hence become useless at the macro level.
3D printing, however, helped to transform these random nano-sized materials into smart particles that could readily perform at the macroscopic level. Adding water sticks the rings of the poly rotaxanes together via hydrogen bonds. The tubular arrays then bind them in an ordered stack. After the printing process, Dr Ke cured them for further use. The cube had a hollow lattice which made it easy to deform. A solvent was used as a catalyst they could switch the molecules from stationary to moving. Hence by removing and adding the solvent, they could make it expand, lifting an object along with it, or return it to its original place.
This mechanism could lead to a wide variety of applications. Molecular machines could be used as soft robots replicating the tasks of a human hand. Jean-Pierre Sauvage, Sir J. Fraser Stoddart, and Bernard L. Feringa are the three scientists on whose research the Nobel Prize-winning research was performed. The study was documented in a paper entitled “Ring Shuttling Controls Macroscopic Motion in a Three-Dimensional Printed Polyrotaxane Monolith”.