文献类型：期刊文献

英文题名：Exploiting Catalytic Steric Hindrance for Enhanced Tishchenko Polymerization: Toward Biorenewable Aromatic Polyesters

作者：Qiang, Hongru[1];Liang, Xue[1];Wang, Wenli[1];Jiang, Jiayun[1];Li, Jianrui[1];Hong, Kai[1];Du, Jianzhong[2,3,4];Zhu, Yunqing[1]

机构：[1]Tongji Univ, Sch Mat Sci & Engn, Dept Polymer Mat, 4800 Caoan Rd, Shanghai 201804, Peoples R China;[2]Tongji Univ, Shanghai Peoples Hosp 4, Translat Res Inst Brain & Brain Like Intelligence, Clin Res Ctr Anesthesiol & Perioperat Med,Dept Gyn, Shanghai 200434, Peoples R China;[3]Tongji Univ, Sch Mat Sci & Engn, Key Lab Adv Civil Engn Mat, Minist Educ, 4800 Caoan Rd, Shanghai 201804, Peoples R China;[4]East China Univ Sci & Technol, Sch Mat Sci & Engn, Shanghai 200237, Peoples R China

年份：2024

卷号：57

期号：22

起止页码：10576

外文期刊名：MACROMOLECULES

收录：;EI(收录号：20244617363164);WOS:【SCI-EXPANDED(收录号:WOS:001350099700001)】；

基金：This work was supported by the National Natural Science Foundation of China (22175131, 22335005, and 21925505), the National Key R&D Program of China (2022YFC2402900), Innovation Program of Shanghai Municipal Education Commission (2023ZKZD28), and the Interdisciplinary Collaborative Research Project of Tongji University (2023-2-YB-03) and Tongcheng Youth Research and Development Fund (CPCIF-RA-0104). J.D. is a recipient of National Science Fund for Distinguished Young Scholars.

语种：英文

外文关键词：Aromatization - Methyl ester - Oligomers - Polymerization - Synthesis (chemical)

摘要：Tishchenko reaction represents a highly atom-efficient method for synthesizing esters via aldehydes disproportionation, which holds significant promise in sustainable chemistry for polymerizing biorenewable dialdehydes into polyesters. However, previous Tishchenko polymerization attempts merely yielded oligomers with very low molecular weights due to intramolecular cyclization. To address this important challenge, we propose an efficient approach to leverage catalytic steric hindrance to achieve higher molecular weights. The investigation of six catalysts revealed that Al(OEt)3, with its three ethoxy groups initiating, imparts significant steric hindrance around the metal center and effectively prevents cyclization termination at the initial stage of polymerization, resulting in aromatic polyesters with a record M- w of 26.6 kg/mol. This breakthrough signals the potential of enhancing catalytic steric hindrance to overcome the low-molecular-weight limitation of Tishchenko polymerization. Building upon this discovery, we synthesized a series of biorenewable meta-substituted dialdehyde monomers (M1-M4) derived from vanillin to afford aromatic polyesters P(M1)-P(M4). These polymers offer tunable thermal properties through molecular weight and side chain flexibility adjustments, exhibiting high thermal stability (T- d,(5%) > 208 degrees C) and controllable glass transition temperatures (1-58 degrees C), and are degradable under mild conditions. This work highlights the importance of developing new methods to utilize readily available bioderived molecules, which is of great value for the sustainable economy.