Garcia Espinosa Luis D, Williams-Pavlantos Kayla, Turney Keaton M, Wesdemiotis Chrys, Eagan James M
School of Polymer Science and Polymer Engineering, The University of Akron, Akron, Ohio 44325-3909, United States.
Department of Chemistry, The University of Akron, Akron, Ohio 44325-3909, Unites States.
ACS Macro Lett. 2021 Oct 19;10(10):1254-1259. doi: 10.1021/acsmacrolett.1c00523. Epub 2021 Oct 3.
The utilization of carbon dioxide as a polymer feedstock is an ongoing challenge. This report describes the catalytic conversion of carbon dioxide and an olefin comonomer, 1,3-butadiene, into a polymer structure that arises from divergent propagation mechanisms. Disubstituted unsaturated δ-valerolactone (EVL) was homopolymerized by the bifunctional organocatalyst 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) to produce a hydrolytically degradable polymer. Isolation and characterization of reaction intermediates using H, C, COSY, HSQC, and MS techniques revealed a vinylogous 1,4-conjugate addition dimer forms in addition to polymeric materials. Polymer number-average molecular weights up to 3760 g/mol and glass transition temperatures in the range of 25-52 °C were measured by GPC and DSC, respectively. The polymer microstructure was characterized by H, C, FTIR, MALDI-TOF MS, and ESI tandem MS/MS. The olefin/CO-derived materials depolymerized by hydrolysis at 80 °C in 1 M NaOH. This method and the observed chemical structures expand the materials and properties that can be obtained from carbon dioxide and olefin feedstocks.
将二氧化碳用作聚合物原料仍是一项持续存在的挑战。本报告描述了将二氧化碳与烯烃共聚单体1,3 - 丁二烯催化转化为一种由不同增长机制产生的聚合物结构的过程。双官能有机催化剂1,5,7 - 三氮杂双环[4.4.0]癸 - 5 - 烯（TBD）使二取代不饱和δ - 戊内酯（EVL）进行均聚，以制备可水解降解的聚合物。使用氢谱、碳谱、COSY谱、HSQC谱和质谱技术对反应中间体进行分离和表征，结果显示除了聚合物材料外，还形成了一种烯丙型1,4 - 共轭加成二聚体。通过凝胶渗透色谱法（GPC）和差示扫描量热法（DSC）分别测得聚合物的数均分子量高达3760 g/mol，玻璃化转变温度在25 - 52℃范围内。通过氢谱、碳谱、傅里叶变换红外光谱（FTIR）、基质辅助激光解吸电离飞行时间质谱（MALDI - TOF MS）和电喷雾串联质谱（ESI tandem MS/MS）对聚合物微观结构进行了表征。由烯烃/一氧化碳衍生的材料在80℃下于1 M氢氧化钠中通过水解发生解聚。这种方法以及所观察到的化学结构扩展了可从二氧化碳和烯烃原料获得的材料种类和性能范围。
