title: Photoresponsive Amphiphilic Macrocycles Containing Main-Chain Azobenzene Polymers.
abstract: Herein, the first example of photosensitive cyclic amphiphilic homopolymers consisting of multiple biphenyl azobenzene chromophores in the cyclic main chain tethered with hydrophilic tetraethylene glycol monomethyl ether units is presented. The synthetic approach involves sequentially performed thermal catalyzed "click" step-growth polymerization in bulk, and Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) intramolecular cyclization from α-alkyne/ω-azide linear precursors. It is observed that such amphiphilic macrocycles exhibit increased glass transition temperatures (Tg ), slightly faster trans-cis-trans photoisomerization, and enhanced fluorescence emission intensity compared with the corresponding linear polymers. In addition, the cyclic amphiphilic homopolymers self-assemble into spherical nanoparticles with smaller sizes which possess slower photoresponsive behaviors in a tetrahydrofuran/water mixture compared with those of the linear ones. All these interesting observations suggest that the cyclic topology has a great influence on the physical properties and self-assembly behavior of these photoresponsive amphiphilic macrocycles in general.
authors.affiliation: Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China.
authors.forename: Yadong
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Dr., La Jolla, CA, 92093, USA.
authors.forename: Zhao
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Dr., La Jolla, CA, 92093, USA.
authors.forename: Yiwen
authors.initials: Y
authors.lastname: Li
authors.affiliation: Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China.
authors.forename: Zhengbiao
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China.
authors.forename: Xiangqiang
authors.initials: X
authors.lastname: Pan
authors.affiliation: Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China.
authors.forename: Nianchen
authors.initials: N
authors.lastname: Zhou
authors.affiliation: Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China.
authors.forename: Xiulin
authors.initials: X
authors.lastname: Zhu
mesh_terms: D001391:Azo Compounds / Q000737:chemistry*; D057930:Click Chemistry; D003500:Cyclization; D057927:Hydrophobic and Hydrophilic Interactions; D007536:Isomerism; D008027:Light; D053758:Nanoparticles / Q000737:chemistry; D010316:Particle Size; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry*; D044366:Transition Temperature
chemical_list: D001391:Azo Compounds; D011108:Polymers; C009850:azobenzene
keywords: amphiphilic macrocycles; azobenzene; photo­responsive polymers; self-assembly