title: Synthesis of High Molecular Weight Cyclic Poly(ε-caprolactone)s of Variable Ring Size Based on a Light-Induced Ring-Closure Approach.
abstract: High molecular weight cyclic poly(ε-caprolactone)s (cPCLs) with variable ring size are synthesized via light-induced ring closure of α,ω-anthracene-terminated PCL (An-PCL-An). The ring size of cPCL is tunable simply by adjusting the polymer concentration from 10 to 100 mg mL(-1) in THF. The cyclo-addition via the bimolecular cyclization of An-PC-An is well characterized by a variety of analyses such as (1) H NMR and UV-vis spectroscopies, gel-permeation chromatography, and differential scanning calorimetry. The reversible dimerization of An induced by heating enables the cyclic PCL to have a switchable "on-off" capability. This novel light-induced ring-closure technique can be one of the most powerful candidates for producing various well-defined cyclic polymers in highly concentrated polymer solution.
authors.affiliation: Department of Polymer Science and Engineering, Hebei University of Technology, No. 8 Guangrong Road, Hongqiao District Tianjin, 300130, China.
authors.forename: Haodi
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Polymer Science and Engineering, Hebei University of Technology, No. 8 Guangrong Road, Hongqiao District Tianjin, 300130, China.
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Department of Polymer Science and Engineering, Hebei University of Technology, No. 8 Guangrong Road, Hongqiao District Tianjin, 300130, China.
authors.forename: Binyuan
authors.initials: B
authors.lastname: Liu
authors.affiliation: Department of Polymer Science and Engineering, Hebei University of Technology, No. 8 Guangrong Road, Hongqiao District Tianjin, 300130, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Han
authors.affiliation: Department of Polymer Science and Engineering, Hebei University of Technology, No. 8 Guangrong Road, Hongqiao District Tianjin, 300130, China.
authors.forename: Zhongyu
authors.initials: Z
authors.lastname: Duan
authors.affiliation: Department of Polymer Science and Engineering, Hebei University of Technology, No. 8 Guangrong Road, Hongqiao District Tianjin, 300130, China.
authors.forename: Cuiyun
authors.initials: C
authors.lastname: Qi
authors.affiliation: BK21 PLUS Center for Advanced Chemical Technology, Department of Chemical Engineering Polymer Science, and Engineering, Pusan National University, Pusan, 609-735, Republic of Korea.
authors.forename: Dae-Won
authors.initials: DW
authors.lastname: Park
authors.affiliation: BK21 PLUS Center for Advanced Chemical Technology, Department of Chemical Engineering Polymer Science, and Engineering, Pusan National University, Pusan, 609-735, Republic of Korea.
authors.forename: Il
authors.initials: I
authors.lastname: Kim
mesh_terms: D008027:Light; D008970:Molecular Weight; D011091:Polyesters / Q000138:chemical synthesis* / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*
chemical_list: D011091:Polyesters; D011108:Polymers; C016240:polycaprolactone
keywords: cyclic polymers; photodimerization; poly(ε-caprolactone); ring-opening polymerization