TY - JOUR
T1 - Convenient and Robust Route to Photoswitchable Hierarchical Liquid Crystal Polymer Stripes via Flow-Enabled Self-Assembly
AU - Li, Xiao
AU - Li, Bo
AU - He, Ming
AU - Wang, Wei
AU - Wang, Tianjie
AU - Wang, Aurelia
AU - Yu, Jiwoo
AU - Wang, Zhonglin
AU - Hong, Suck Won
AU - Byun, Myunghwan
AU - Lin, Shaoliang
AU - Yu, Haifeng
AU - Lin, Zhiqun
N1 - Funding Information:
This work is supported by the Air Force Office of Scientific Research (FA9550-16-1-0187), the National Science Foundation (CMMI 1562075 and 1727313; DMR 1709420), and National Natural Science Foundation of China (grant nos. 51322301, 51573005, 51622301, and 51573046). This research was also supported by the BK21 Plus program through the National Research Foundation of Korea funded by the Ministry of Education. X.L. gratefully acknowledges the financial support from the China Scholarship Council.
Publisher Copyright:
© 2018 American Chemical Society.
PY - 2018/2/7
Y1 - 2018/2/7
N2 - Hierarchically arranged stripes of photoswitchable liquid crystal polymers (LCPs) containing azobenzene moieties were conveniently crafted via a flow-enabled self-assembly (FESA). Interestingly, by subjecting a drop of LCP solution to dry in a restricted geometry comprising two nearly parallel plates with a stationary upper plate and a movable lower plate that programmably traveled in a "stop-and-move" manner during the FESA process, photoswitchable LCP stripes were yielded, displaying two modes of deposition, namely, periodic primary stripes of large dimensions and regularly spaced secondary stripes of small dimensions situated between adjacent primary stripes (i.e., forming hierarchical LCP stripes). Notably, these hierarchical azobenzene moieties-containing stripes demonstrated sequential photoinduced reversible phase transition (i.e., photoswitching) due to the thickness difference between primary and secondary stripes. A UV light-induced expansion effect was observed on the LCP stripes. Clearly, such rapid creation of hierarchical stripes by FESA represents a robust means of organizing polymers, nanoparticles, colloids, DNA, etc. into complex yet ordered patterns over a large area in a simple and controllable manner for potential use in surface relief grating, photoactuators, photoswitchable devices, antifake labels, etc.
AB - Hierarchically arranged stripes of photoswitchable liquid crystal polymers (LCPs) containing azobenzene moieties were conveniently crafted via a flow-enabled self-assembly (FESA). Interestingly, by subjecting a drop of LCP solution to dry in a restricted geometry comprising two nearly parallel plates with a stationary upper plate and a movable lower plate that programmably traveled in a "stop-and-move" manner during the FESA process, photoswitchable LCP stripes were yielded, displaying two modes of deposition, namely, periodic primary stripes of large dimensions and regularly spaced secondary stripes of small dimensions situated between adjacent primary stripes (i.e., forming hierarchical LCP stripes). Notably, these hierarchical azobenzene moieties-containing stripes demonstrated sequential photoinduced reversible phase transition (i.e., photoswitching) due to the thickness difference between primary and secondary stripes. A UV light-induced expansion effect was observed on the LCP stripes. Clearly, such rapid creation of hierarchical stripes by FESA represents a robust means of organizing polymers, nanoparticles, colloids, DNA, etc. into complex yet ordered patterns over a large area in a simple and controllable manner for potential use in surface relief grating, photoactuators, photoswitchable devices, antifake labels, etc.
KW - azo-containing liquid crystalline polymer
KW - flow-enabled self-assembly
KW - hierarchical structure
KW - photoexpansion effect
KW - photoinduced phase transition
UR - http://www.scopus.com/inward/record.url?scp=85041919824&partnerID=8YFLogxK
U2 - 10.1021/acsami.7b16001
DO - 10.1021/acsami.7b16001
M3 - Article
C2 - 29308640
AN - SCOPUS:85041919824
SN - 1944-8244
VL - 10
SP - 4961
EP - 4970
JO - ACS Applied Materials and Interfaces
JF - ACS Applied Materials and Interfaces
IS - 5
ER -