Facile Synthesis of Well-Defined MDMO-PPV Containing (Tri)Block—Copolymers via Controlled Radical Polymerization and CuAAC Conjugation

Polymers

Neomy Zaquen¹  Joke Vandenbergh¹  Maria Schneider-Baumann²  Laurence Lutsen³  Dirk Vanderzande¹  Thomas Junkers¹ 

[1] Polymer Reaction Design (PRD) Group, Instituut voor Materiaalonderzoek (IMO), Hasselt University, Agoralaan Building D, Diepenbeek B-3590, Belgium; E-Mails:;Institute for Polymer Chemistry and Chemical Technology, Preparative Macromolecular Chemistry, Karlsruhe Institute of Technology, Engesser str. 18, Karlsruhe 76128, Germany; E-Mail:;IMEC associated laboratory IMOMEC, Wetenschapspark 1, Diepenbeek B-3590, Belgium; E-Mail:

关键词: poly(p-phenylene vinylene);    MDMO-PPV;    radical polymerization;    chain transfer polymerization;    (tri)block copolymers;    ATRP;    CuAAC;   

DOI  :  10.3390/polym7030418

来源: mdpi

【 摘 要 】

A systematic investigation into the chain transfer polymerization of the so-called radical precursor polymerization of poly(p-phenylene vinylene) (PPV) materials is presented. Polymerizations are characterized by systematic variation of chain transfer agent (CTA) concentration and reaction temperature. For the chain transfer constant, a negative activation energy of −12.8 kJ·mol⁻¹ was deduced. Good control over molecular weight is achieved for both the sulfinyl and the dithiocarbamate route (DTC). PPVs with molecular weights ranging from thousands to ten thousands g·mol⁻¹ were obtained. To allow for a meaningful analysis of the CTA influence, Mark–Houwink–Kuhn–Sakurada (MHKS) parameters were determined for conjugated MDMO-PPV ([2-methoxy-5-(3',7'-dimethyloctyloxy)]-1,4-phenylenevinylene) to α = 0.809 and k = 0.00002 mL·g⁻¹. Further, high-endgroup fidelity of the CBr₄-derived PPVs was proven via chain extension experiments. MDMO-PPV-Br was successfully used as macroinitiator in atom transfer radical polymerization (ATRP) with acrylates and styrene. A more polar PPV counterpart was chain extended by an acrylate in single-electron transfer living radical polymerization (SET-LRP). In a last step, copper-catalyzed azide alkyne cycloaddition (CuAAC) was used to synthesize block copolymer structures. Direct azidation followed by macromolecular conjugation showed only partial success, while the successive chain extension via ATRP followed by CuAAC afforded triblock copolymers of the poly(p-phenylene vinylene)-block-poly(tert-butyl acrylate)-block-poly(ethylene glycol) (PPV-b-PtBuA-b-PEG).

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.