A Multistimuli Responsive, Flexible Luminescent Framework and Its Applicability in Anticounterfeiting

A linear distyrylanthracene derivative (DDATAn) with
two diaminotriazine
(DAT) groups acting as the hydrogen bond (H-bond) units was designed
and synthesized in order to construct flexible organic porous crystals.
H-bonds between the DAT moieties helped the molecules to construct
a double interpenetrated two-dimensional layer, and the stacking between
layers provided a H-bonded organic framework (X-HOF-3) with one-dimensional
solvent channels. When X-HOF-3 was placed in contact with methanol,
the fluorescent colors of the HOF exhibited an apparent bathochromic
shift. More interestingly, the methanol-activated HOF was able to
rapidly adsorb water from the air, which was accompanied by a change
in fluorescent color from yellow to red. Under heating, water was
released from the HOF and the fluorescent color returned to yellow.
Water molecules in the pores were also able to be released after an
applied mechanical force disrupted the ordered structure of the HOF.
Based on these stimuli-responsive properties, these HOFs can be used
as advanced functional materials in anticounterfeiting applications.