title: Synthesis of functionalized asymmetric star polymers containing conductive polyacetylene segments by living anionic polymerization.
abstract: Novel 3-arm ABC, 4-arm ABCD, and 5-arm ABCDE asymmetric star polymers comprising the conductive polyacetylene precursor, poly(4-methylphenyl vinyl sulfoxide) (PMePVSO), and other segments, such as polystyrene, poly(alpha-methylstyrene), poly(4-methoxystyrene), poly(4-trimethylsilylstyrene), and poly(4-methylstyrene), were synthesized by the methodology based on living anionic polymerization using DPE-functionalized polymers. This methodology involves the addition reaction of a DPE-functionalized polymer to a living anionic polymer followed by the living anionic polymerization of MePVSO initiated from the in situ formed polymer anion with two, three, or four polymer segments. The resultant asymmetric star polymers possessed predetermined molecular weights, narrow molecular weight distributions (Mw/Mn < 1.03), and desired compositions as confirmed by SEC, 1H NMR, SLS, and elemental analysis. After thermal treatment, the PMePVSO segment in the star polymer could be completely converted into a conductive polyacetylene segment, evident from TGA and elemental analysis. These asymmetric star polymers are expected to exhibit interesting solution properties and unique microphase-separated morphological suprastructures with potential applications in nanoscopic conductive materials. Moreover, this methodology can afford the target asymmetric star polymers with arm segments varying in a wide range and enables the synthesis of more complex macromolecular architectures.
authors.affiliation: Polymeric and Organic Materials Department, Graduate School of Science and Technology, Tokyo Institute of Technology, H-127, 2-12-1 Ohokayama, Meguro-ku, Tokyo 152-8552, Japan.
authors.forename: Youliang
authors.initials: Y
authors.lastname: Zhao
authors.forename: Tomoya
authors.initials: T
authors.lastname: Higashihara
authors.forename: Kenji
authors.initials: K
authors.lastname: Sugiyama
authors.forename: Akira
authors.initials: A
authors.lastname: Hirao
mesh_terms: D000114:Acetylene / Q000031:analogs & derivatives* / Q000737:chemistry; D000838:Anions / Q000737:chemistry; D004553:Electric Conductivity; D049329:Nanostructures / Q000737:chemistry; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry; D053279:Polyynes; D013696:Temperature
chemical_list: D000838:Anions; D011108:Polymers; D053279:Polyynes; D000114:Acetylene