It
is highly challenging to achieve an optically deformable polymer with
good controllability, stability, and self-healability for fabricating
an optically controlled microrobotics. Here, we present a photo-responsive
self-healing supramolecular assembly cross-linked by 3,3′,5,5′-azobenzenetetracarboxylic
acid (t-Azo) enabling the controllable and stable deformation.
The network (PAA-u) of polyacrylic acid (PAA) grafted with 2-ureido-4[1H]-pyrimidinone (UPy) is formed via multiple intermolecular
hydrogen bonds (H-bonds) between UPy and t-Azo moieties. Molecular
H-bonds stabilize the cis-isomer, enables stress transfer at the interface,
and also contributes to fast healability. The PAA-u/t-Azo assembly
shows a green-light-induced bending deformation, which recovers its
shape under the irradiation of UV light. On the basis of this controllable
and reversible deformation, the PAA-u/t-Azo “hand” realizes
reversible light-driven grabbing and releasing of an object by optimizing
bending and recovery. The assembly also shows a fast and excellent
self-healing performance irradiated by green light during deformation.
The multiple-H-bonding-cross-linked assembly with stable deformation
and fast self-healability can be used for the development of a multitude
of advanced microrobotics.