Comprehensive Report
Potassium Acetate/18-Crown-6 Pair: Robust and Versatile Catalyst for Synthesis of Polyols from Ring-Opening Copolymerization of Epoxides and Cyclic Anhydrides†
Xiaoqing Dou,
Xiao-Hui Liu,
Bin Wang,
Yue-Sheng Li,
Xiaoqing Dou
School of Materials Science and Engineering, Tiangong University, Tianjin, 300387 China
Search for more papers by this authorCorresponding Author
Xiao-Hui Liu
School of Materials Science and Engineering, Tiangong University, Tianjin, 300387 China
E-mail: [email protected]; [email protected]Search for more papers by this authorCorresponding Author
Bin Wang
Tianjin Key Lab of Composite & Functional Materials, School of Materials Science and Engineering, Tianjin University, Tianjin, 300350 China
E-mail: [email protected]; [email protected]Search for more papers by this authorYue-Sheng Li
Tianjin Key Lab of Composite & Functional Materials, School of Materials Science and Engineering, Tianjin University, Tianjin, 300350 China
Search for more papers by this authorXiaoqing Dou,
Xiao-Hui Liu,
Bin Wang,
Yue-Sheng Li,
Xiaoqing Dou
School of Materials Science and Engineering, Tiangong University, Tianjin, 300387 China
Search for more papers by this authorCorresponding Author
Xiao-Hui Liu
School of Materials Science and Engineering, Tiangong University, Tianjin, 300387 China
E-mail: [email protected]; [email protected]Search for more papers by this authorCorresponding Author
Bin Wang
Tianjin Key Lab of Composite & Functional Materials, School of Materials Science and Engineering, Tianjin University, Tianjin, 300350 China
E-mail: [email protected]; [email protected]Search for more papers by this authorYue-Sheng Li
Tianjin Key Lab of Composite & Functional Materials, School of Materials Science and Engineering, Tianjin University, Tianjin, 300350 China
Search for more papers by this author† Dedicated to the Special Issue of Emerging Themes in Polymer Science.
Comprehensive Summary
Efficient synthesis of polyester polyols with tunable molecular weight and microstructures from cyclic anhydride/epoxide mixtures by taking advantage of chain transfer reaction remains a great challenge, because most of the catalysts exhibit poor tolerance to chain transfer agent (CTA). In this contribution, we demonstrated that potassium acetate (KOAc) and 18-crown-6 (18-C-6) combination has great potential in the synthesis of diverse polyester polyols with controllable molecular weight and high-end group fidelity. Compared with KOAc, KOAc/18-C-6 pair could induce a much faster chain transfer between the active and dormant chains, and thus produce polyester polyols with narrow and monomodal distribution. In addition, polyester polyols could be efficiently prepared in laboratory by using commercially available cyclic anhydride without further purification (containing about 2% diacid residual as CTA) with an extremely low catalyst loading ([catalyst pair] : [anhydride] : [epoxide] = 1 : 50000 : 250000, [catalyst pair] = 0.0004 mol%). KOAc/18-C-6 could also promote the self-switchable copolymerization of cyclic anhydride/epoxide/cyclic ester mixtures. Ring- opening copolymerization of cyclic ester was initiated automatically after the full conversion of cyclic anhydride, finally producing polyester polyols with ABA-type block structure.
Supporting Information
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