TY - JOUR
T1 - Synthesis and characterization of liquid crystalline copolymers with dual photochromic pendant groups
AU - Yang, Po Chih
AU - Wu, Ming Zu
AU - Liu, Jui Hsiang
N1 - Funding Information:
The authors thank the National Science Council of the Republic of China (Taiwan) for financially supporting this research under Contract No. NSC 95-2221-E-006-190.
Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.
PY - 2008/6/10
Y1 - 2008/6/10
N2 - In order to study the photoreactivity and the optical properties of liquid crystalline copolymers with multiple photochromic groups, a series of novel liquid crystalline binary and ternary polyacrylates consisting of one (C{double bond, long}C or N{double bond, long}N) or dual (C{double bond, long}C and N{double bond, long}N) photochromic segments were synthesized and characterized considering their liquid crystalline, optical, and photochromic properties and their thermal stability. Achiral homopolymer P1 shows a smectic A phase (fan-shaped texture), and all chiral copolymers CP1-CP6 exhibit chiral nematic phases (cholesteric, oily streaks textures). The polymers show excellent solubility in common organic solvents such as chloroform, toluene, and THF. These polymers also exhibit good thermal stability, with decomposition temperatures (Tds) greater than 373 °C at 5% weight loss, and beyond 440 °C at 50% weight loss under nitrogen atmosphere. UV irradiation caused E/Z photoisomerization at N{double bond, long}N and C{double bond, long}C segments of the synthesized photochromic copolymers leading to reversible and irreversible isomerizations, respectively. The synthesized liquid crystalline ternary copolymer CP6, containing two different photochromic N{double bond, long}N and C{double bond, long}C groups, is sensitive to different UV wavelengths and is notably interesting from the viewpoint of photochromic copolymers.
AB - In order to study the photoreactivity and the optical properties of liquid crystalline copolymers with multiple photochromic groups, a series of novel liquid crystalline binary and ternary polyacrylates consisting of one (C{double bond, long}C or N{double bond, long}N) or dual (C{double bond, long}C and N{double bond, long}N) photochromic segments were synthesized and characterized considering their liquid crystalline, optical, and photochromic properties and their thermal stability. Achiral homopolymer P1 shows a smectic A phase (fan-shaped texture), and all chiral copolymers CP1-CP6 exhibit chiral nematic phases (cholesteric, oily streaks textures). The polymers show excellent solubility in common organic solvents such as chloroform, toluene, and THF. These polymers also exhibit good thermal stability, with decomposition temperatures (Tds) greater than 373 °C at 5% weight loss, and beyond 440 °C at 50% weight loss under nitrogen atmosphere. UV irradiation caused E/Z photoisomerization at N{double bond, long}N and C{double bond, long}C segments of the synthesized photochromic copolymers leading to reversible and irreversible isomerizations, respectively. The synthesized liquid crystalline ternary copolymer CP6, containing two different photochromic N{double bond, long}N and C{double bond, long}C groups, is sensitive to different UV wavelengths and is notably interesting from the viewpoint of photochromic copolymers.
UR - http://www.scopus.com/inward/record.url?scp=44549083783&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=44549083783&partnerID=8YFLogxK
U2 - 10.1016/j.polymer.2008.04.036
DO - 10.1016/j.polymer.2008.04.036
M3 - Article
AN - SCOPUS:44549083783
SN - 0032-3861
VL - 49
SP - 2845
EP - 2856
JO - polymer
JF - polymer
IS - 12
ER -