International Journal

Multimaterial 4D Printing with Tailorable Shape Memory Polymers
Author
Q. Ge*, A. H. Sakhaei, Howon Lee, C. K. Dunn, Nicholas. X. Fang*, and M. L. Dunn*
Journal
Scientific Reports
Vol
6
Page
31110
Year
2016
File
2016_Sci. Rep..pdf (6.8M) 7회 다운로드 DATE : 2022-03-07 10:43:00

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We present a new 4D printing approach that can create high resolution (up to a few microns), multimaterial shape memory polymer (SMP) architectures. The approach is based on high resolution projection microstereolithography (PμSL) and uses a family of photo-curable methacrylate based copolymer networks. We designed the constituents and compositions to exhibit desired thermomechanical behavior (including rubbery modulus, glass transition temperature and failure strain which is more than 300% and larger than any existing printable materials) to enable controlled shape memory behavior. We used a high resolution, high contrast digital micro display to ensure high resolution of photo-curing methacrylate based SMPs that requires higher exposure energy than more common acrylate based polymers. An automated material exchange process enables the manufacture of 3D composite architectures from multiple photo-curable SMPs. In order to understand the behavior of the 3D composite microarchitectures, we carry out high fidelity computational simulations of their complex nonlinear, time-dependent behavior and study important design considerations including local deformation, shape fixity and free recovery rate. Simulations are in good agreement with experiments for a series of single and multimaterial components and can be used to facilitate the design of SMP 3D structures.