Polymer origami: programming the folding with shape

The design of three-dimensional (3D) microstructures is an interesting, fascinating and highly challenging research topic. One of the very promising approaches for 3D microstructuring, inspired by the Japanese art of paper folding-origami, is based on self-folding films. Such films consist of two kinds of materials with different volume expansion properties and are able to form different structures ranging from simple tubes to highly complex 3D shapes. In this review, our recent progress in the design of polymer bilayers and understanding of their folding is summarized.