Quasiliving cationic ring-opening polymerization of 2-ethyl-2-oxazoline in benzotrifluoride, as an alternative reaction medium

POLYMER

卷:212

Article

Pasztoi, Balazs^1,2  Trotschler, Tobias M.^3,4,5  Szabo, Akos¹  Kerscher, Benjamin^3,4  Tenhu, Heikki⁶  Muelhaupt, Rolf^3,4,5  Ivan, Bela¹ 

[1] Res Ctr Nat Sci, Inst Mat & Environm Chem, Polymer Chem Res Grp, Magyar Tudosok Krt 2, H-1117 Budapest, Hungary

[2] Eotvos Lorand Univ, Fac Sci, Inst Chem, George Hevesy PhD Sch Chem, Pazmany Peter Setany 2, H-1117 Budapest, Hungary

[3] Univ Freiburg, Inst Macromol Chem, Stefan Meier Str 31, D-79104 Freiburg, Germany

[4] Univ Freiburg, Freiburg Mat Res Ctr FMF, Stefan Meier Str 21, D-79104 Freiburg, Germany

[5] Univ Freiburg, Freiburg Ctr Interact Mat & Bioinspired Technol F, Georges Kohler Allee 105, D-79110 Freiburg, Germany

[6] Univ Helsinki, Dept Chem, AI Virtasen Aukio 1, FI-00014 Helsinki, Finland

关键词: Polyoxazoline;    Cationic ring-opening polymerization;    Quasiliving polymerization;    Benzotrifluoride;    Environmentally advantageous;   

DOI  :  10.1016/j.polymer.2020.123165

来源: Elsevier

【 摘 要 】

Cationic ring-opening polymerization (CROP) of 2-ethyl-2-oxazoline (EtOx) was systematically investigated in benzotrifluoride (BTF), which is considered as an environmentally less harmful solvent than many conventional reaction media. Simultaneously, polymerizations in conventional solvents, such as acetonitrile, N,N-dimethylacetamide and toluene, were also carried out for comparison in the 80-100 degrees C temperature range. Kinetic experiments revealed that the monomer consumption occurs by first order kinetics and the number average molecular weights linearly increase in line with the theoretical molecular weight as a function of monomer conversion. These findings indicate that the polymerization takes place by quasiliving CROP in all the investigated solvents, including BTF as well, resulting in PEtOx with prederminded molecular weights and polydispersities of 1.3-15. The highest polymerization rates were obtained in BTF, resulting in high conversions in short reaction times at 100 degrees C reaction temperature. The Arrhenius parameters of the polymerization of EtOx in BTF indicates relatively high activation energy in comparison with other applied solvents, however, a compensation effect between the activation energies and frequency factor is observed for such polymerization in a variety of solvents. Our findings are expected to enable the convenient synthesis of polyoxazolines and polyoxazoline-based well-defined polymer architectures in BTF, an environmentally advantageous alternative solvent to harmful polymerization media, with high polymerization rates in short reaction times without the need for any special conditions or equipment.

【 授权许可】

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