Scientists in the United States have developed ‘flat pack’ polymer structures that can autonomously assemble into three-dimensional shapes on application of an electric current.
Research published in Soft Matter describes the use of heat-triggered shape memory polymers to build 3D structures without the need for sophisticated printers.
The researcher shows that, by printing shape memory polymers (SMPs) onto laser-cut joints with conductive coatings, they can separate the assembly process entirely from the original printing of the 2D material.
The scientists printed an SMP in a deformed, flat state and aligned with a resistive circuit over a scored substrate – in this case, paper. By running an electric current through the circuit, joule heating activates the phase transformation of the polymer back into its original state and folds the paper. As this combination is electrically triggered, it allows both simultaneous and sequential folding of complicated structures.
S M Felton et al, Soft Matter, 2013.