title: Acyclic diene metathesis polymerization and heck polymer-polymer conjugation for the synthesis of star-shaped block copolymers.
abstract: Three- and four-arm star shaped polymers, as well as diblock copolymers, are synthesized via acyclic diene metathesis (ADMET) polymerization. This is accomplished by using an asymmetric α,ω-diene containing a terminal double bond and an acrylate, which is polymerized in the presence of multifunctional acrylates as selective and irreversible chain transfer agents using Hoveyda-Grubbs second generation catalyst. High cross-metathesis selectivities are achieved at low temperatures enabling good control over molecular weights. Furthermore, additional polyethyleneglycol (PEG) blocks are attached to these polymers via Heck coupling of the acrylate end-groups of these polymers with aryl iodide functionalized PEG, obtaining three- and four-arm star shaped di- and triblock copolymers with molecular weights up to 31 kDa.
authors.affiliation: Karlsruhe Institute of Technology (KIT), Institute of Organic Chemistry, Fritz-Haber-Weg 6, 76131, Karlsruhe, Germany.
authors.forename: Lucas Montero
authors.initials: LM
authors.lastname: de Espinosa
authors.forename: Matthias
authors.initials: M
authors.lastname: Winkler
authors.forename: Michael A R
authors.initials: MA
authors.lastname: Meier
mesh_terms: D000179:Acrylates / Q000737:chemistry*; D000180:Acrylic Resins / Q000138:chemical synthesis* / Q000737:chemistry; D000475:Alkenes / Q000737:chemistry*; D002384:Catalysis; D011092:Polyethylene Glycols / Q000737:chemistry*
chemical_list: D000179:Acrylates; D000180:Acrylic Resins; D000475:Alkenes; D011092:Polyethylene Glycols; C006903:carbopol 940; C036658:acrylic acid
keywords: ADMET; Heck coupling; block copolymers; polymer-polymer conjugation; star-shaped polymer