Hongyao Ding; Xiaoxu Liang; Si Yu Zheng; Qiao Wang; Zongjin Li; Guoxing Sun. Actuators assembled from hydrogel blocks of various shapes via condensation reactions. Mater. Chem. Phys. 2020, 253, 8. DOI: 10.1016/j.matchemphys.2020.123332.