Research Progress in Precision Polymerization of Polar Olefin Monomers by Lewis Pairs★

doi:10.6023/A23050196

Acta Chimica Sinica ›› 2023, Vol. 81 ›› Issue (9): 1215-1230.DOI: 10.6023/A23050196 Previous Articles Next Articles

Special Issue: 庆祝《化学学报》创刊90周年合辑

Review

Lewis酸碱对催化极性烯烃单体精准聚合的研究进展^★

万义, 何江华^*(), 张越涛^*()

吉林大学化学学院超分子结构与材料国家重点实验室长春 130012

投稿日期:2023-05-04 发布日期:2023-06-06

作者简介:

万义, 吉林大学在读博士研究生. 2018年于辽宁大学化学院获得材料化学理学学士学位, 同年9月进入吉林大学化学学院有机化学专业攻读硕士学位, 2020年9月至今以硕博连读形式攻读博士学位, 硕博期间的导师是张越涛教授. 主要研究方向包括: (1)新型Lewis酸碱对催化体系和生物质基单体的开发、(2)高分子精准合成和功能化聚合物材料制备.

何江华, 吉林大学副教授. 1999年于长春师范学院化学系获得化学教育学士学位, 2002年于东北师范大学化学系获得无机化学硕士学位, 2005年于吉林大学化学学院获得无机化学博士学位. 2007年于美国科罗拉多州立大学从事博士后研究, 并于2013年晋升为一级研究员. 2015年至今任吉林大学副教授, 硕士生导师. 研究方向主要集中于可再生高分子的合成和生物质高附加值转化. 目前以项目负责人身份主持国家自然科学基金面上项目两项, 以通讯作者身份在Angew. Chem. Int. Ed., Sci. Bull., Green Chem.和Org. Chem. Front.等国际知名高水平期刊发表SCI论文20余篇.

张越涛, 吉林大学“唐敖庆学者”卓越教授. 1999年于吉林大学化学学院获得化学学士学位, 2004年于同校获得有机化学理学博士学位, 同年留校工作. 2006年赴美国科罗拉多州立大学从事博士后研究, 并于2009年晋升为二级研究员. 2013年至今任吉林大学教授, 博士生导师. 主要研究方向包括: (1) FLP催化聚合物精准合成、(2)生物质降解制备精细化学品和生物燃料、(3)有机合成方法学. 截至目前, 以项目负责人身份主持国家杰出青年科学基金、NSFC优秀青年科学基金, 国家自然科学基金面上项目等科研项目多项, 以通讯作者身份在Nat. Chem., J. Am. Chem. Soc., Angew. Chem. Int. Ed., Nat. Commun., CCS Chem., Sci. Bull., ACS Catal., Chem. Sci.和Green Chem.等国际知名高水平期刊发表SCI论文50余篇, 授权中国专利18项.

^★庆祝《化学学报》创刊90周年.

基金资助:
国家自然科学基金(22225104); 国家自然科学基金(22071077); 国家自然科学基金(21871107); 国家自然科学基金(21975102)

Research Progress in Precision Polymerization of Polar Olefin Monomers by Lewis Pairs^★

Yi Wan, Jianghua He(), Yuetao Zhang()

State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, 130012

Received:2023-05-04 Published:2023-06-06
Contact: *E-mail: hjh2015@jlu.edu.cn; ytzhang2009@jlu.edu.cn
About author:
^★Dedicated to the 90th anniversary of Acta Chimica Sinica.
Supported by:
The National Natural Science Foundation of China(22225104); The National Natural Science Foundation of China(22071077); The National Natural Science Foundation of China(21871107); The National Natural Science Foundation of China(21975102)

As a newly emerged polymerization strategy, Lewis pair polymerization (LPP) has been widely used in the polymerization of polar olefin monomers and the preparation of functional materials in recent years. With its unique polymerization mechanism and kinetic characteristics, LPP has shown many advantages over the traditional polymerization methods, and accomplished many challenging tasks in polymer synthesis. This review systematically summarizes the research progress of the precision polymerization of the polar olefin monomers into polymers catalyzed by Lewis pairs in terms of molecular weight, molecular weight distribution, stereochemistry, monomer sequence and polymer topology, and proposes the outlook for the problems and challenges existing in the development of LPP.

Key words: Lewis pair, living polymerization, polar olefin monomer, precision polymer synthesis

Cite this article

Yi Wan, Jianghua He, Yuetao Zhang. Research Progress in Precision Polymerization of Polar Olefin Monomers by Lewis Pairs^★[J]. Acta Chimica Sinica, 2023, 81(9): 1215-1230.

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Fig. & Tab. 17

Figure 1. (a) Classification of Lewis pairs; (b) mechanism of Lewis pair polymerization

Figure 2. (a) Living polymerization of MMA catalyzed by (BHT)2AlMe/NHO1 LP; (b) MALDI-TOF mass spectrum of the low-MW PMMA; (c) plots of Mn and ? for the PMMA vs [MMA]0/[NHO1] ratio; (d) Plots of Mn and ? for the PMMA vs MMA conversion; (e) GPC traces of PMMA samples obtained from chain extension; (f) GPC traces of homopolymer, diblock and ABA triblock copolymer produced from the sequential block copolymerization of MMA and BnMA

Figure 3. Chemoselective and living/controlled polymerization of divinyl polar monomers catalyzed by (BHT)2AlMe/NHO LP

Figure 4. (a) GPC traces of PMMA with different molecular weight, catalytic system: P(NIiPr)Ph2/(BHT)AliBu2 LP; (b) GPC traces of homopolymer, diblock and ABA triblock copolymer produced from the sequential block copolymerization of MMBL and MBL, catalytic system: P(NIiPr)Ph2/(BHT)2AliBu LP

Figure 5. (a) Living/controlled polymerization of acrylates monomers catalyzed by B(2,4-F2C6H3)3/PiBu3 LP; (b) MALDI-TOF mass spectrum of the low-MW PMA and a plot of m/z values (y) vs the number of PMA repeat units (x) for molecular ion peaks; (c) GPC curves for PMA, PMA-b-PEA diblock, PMA-b-PEA-b-PnBA triblock, and PMA-b-PEA-b-PnBA-b-PtBA tetrablock copolymers

Figure 6. Living/controlled polymerization of biomass-derived methylene butyrolactones catalyzed by (BHT)2AlMe/IiPr LP

Figure 7. (a) Sequence-controlled polymers synthesized by P(NIiPr)Ph2/(BHT)AliBu2 LP; (b) GPC curves of sequence controllable polymers with different block number; (c) products obtained from the scale up synthesis of the high-molecular-weight pentablock copolymers after five successive addition of monomers

Figure 8. (a) The monomers applied to LP-PISA; (b) LP-PISA catalyzed by (BHT)AliBu2/NHO2 LP; (c) [TFEMA]t/[TFEMA]0 vs. time plot at r.t., condition: [PDMAEA]0∶[PTFEMA]0=75∶400, solid content with a mass fraction of 15%; (d) TEM images of spheres (1), worms (2), vesicles (3), and nanofibers (4)

Figure 9. (a) The synthesis of ABA triblock copolymers in one pot and two steps; (b) the synthesis of ABA triblock copolymers in one pot and one step; (c) mechanical properties of TPEs; (d) elasticity of TPEs; (e) mechanical properties of TPEs at high temperature; (f) optical properties of TPEs

Figure 10. (a) Lewis acid affinity sequence and homopolymerization activity sequence of different monomers; (b) sequence copolymers were prepared using different Lewis acid affinity and polymerization activity relationships

Figure 11. (a) Catalysts and (b) monomers for the synthesis of sequence-controlled polymers; (c) schematic diagram of synthesis of sequence-controlled polymers

Figure 12. (a) The living/controlled and 100% 1, 4-selective polymerization of conjugated polar olefin monomers catalyzed by (BHT)2AlPh/NHO LP; (b) post-modification of poly(methyl polysorbate)

Figure 13. Living/controlled polymerization of semi-fluorinated methacrylate monomer catalyzed by (BHT)2AlMe/ItBu LP and the preparation of stereocomplex

Figure 14. Stereoselective polymerization of MMA catalyzed by intramolecular rare-earth metal based Lewis pairs

Figure 15. Synthesis of (a) cyclic PMS and (b) cyclic PMMA

Figure 16. (a) The mechanism of linear polymers synthesis by (BHT)2AlMe/TPT LP; (b) the synthesis of cyclic block copolymers based on (BHT)2AlMe/ItBu/MS; (c) the mechanism of cyclic polymers synthesis by (BHT)2AlMe/ItBu LP

Figure 17. (a) MALDI-TOF mass spectrum of low molecular weight cyclic PMMBL; (b) comparison of Mark-Houwink curves between cyclic PMMBL and linear PMMBL; (c) the synthesis of cyclic polymers catalyzed by trifunctional Lewis pair

References 60

[1]	Jehanno, C.; Alty, J. W.; Roosen, M.; De Meester, S.; Dove, A. P.; Chen, E. Y.-X.; Leibfarth, F. A.; Sardon, H. Nature 2022, 603, 803. doi: 10.1038/s41586-021-04350-0
[2]	Cywar, R. M.; Rorrer, N. A.; Hoyt, C. B.; Beckham, G. T.; Chen, E. Y.-X. Nat. Rev. Mater. 2022, 7, 83. doi: 10.1038/s41578-021-00363-3
[3]	Andrady, A. L.; Neal, M. A. Phil. Trans. R. Soc. B 2009, 364, 1977. doi: 10.1098/rstb.2008.0304
[4]	Hong, M.; Chen, J.; Chen, E. Y.-X. Chem. Rev. 2018, 118, 10551. doi: 10.1021/acs.chemrev.8b00352
[5]	Stephan, D. W.; Erker, G. Angew. Chem. Int. Ed. 2015, 54, 6400. doi: 10.1002/anie.201409800
[6]	Stephan, D. W. Science 2016, 354, aaf7229. doi: 10.1126/science.aaf7229
[7]	Lam, J.; Szkop, K. M.; Mosaferi, E.; Stephan, D. W. Chem. Soc. Rev. 2019, 48, 3592. doi: 10.1039/C8CS00277K
[8]	Guan, Y.; Chang, K.; Sun, Q.; Xu, X. Chin. J. Org. Chem. 2022, 42, 1326. (in Chinese) doi: 10.6023/cjoc202112008
	(管怡雯, 常克俭, 孙千林, 徐信, 有机化学, 2022, 42, 1326.) doi: 10.6023/cjoc202112008
[9]	Zhang, Y.; Miyake, G. M.; Chen, E. Y.-X. Angew. Chem. Int. Ed. 2010, 49, 10158. doi: 10.1002/anie.201005534
[10]	Zhang, Y.; Miyake, G. M.; John, M. G.; Falivene, L.; Caporaso, L.; Cavallo, L.; Chen, E. Y.-X. Dalton Trans. 2012, 41, 9119. doi: 10.1039/c2dt30427a
[11]	He, J.; Zhang, Y.; Falivene, L.; Caporaso, L.; Cavallo, L.; Chen, E. Y.-X. Macromolecules 2014, 47, 7765. doi: 10.1021/ma5019389
[12]	Jia, Y.-B.; Wang, Y.-B.; Ren, W.-M.; Xu, T.; Wang, J.; Lu, X.-B. Macromolecules 2014, 47, 1966. doi: 10.1021/ma500047d
[13]	Knaus, M. G. M.; Giuman, M. M.; Pöthig, A.; Rieger, B. J. Am. Chem. Soc. 2016, 138, 7776. doi: 10.1021/jacs.6b04129
[14]	Xu, P.; Yao, Y.; Xu, X. Chemistry 2017, 23, 1263.
[15]	Xu, T.; Li, C. Prog. Chem. 2015, 27, 1087. (in Chinese)
	(徐铁齐, 李长宏, 化学进展, 2015, 27, 1087.) doi: 10.7536/PC150166
[16]	Zhao, W.; He, J.; Zhang, Y. Sci. Bull. 2019, 64, 1830. doi: 10.1016/j.scib.2019.08.025
[17]	Bai, Y.; Zhang, Y.-T. Acta Polymerica Sinica 2019, 50, 233. (in Chinese)
	(白云, 张越涛, 高分子学报, 2019, 50, 233.)
[18]	Wang, Q.; Zhao, W.; Zhang, S.; He, J.; Zhang, Y.; Chen, E. Y.-X. ACS Catal. 2018, 8, 3571. doi: 10.1021/acscatal.8b00333
[19]	Wang, H.; Wang, Q.; He, J.; Zhang, Y. Polym. Chem. 2019, 10, 3597. doi: 10.1039/C9PY00427K
[20]	Jia, Y.-B.; Ren, W.-M.; Liu, S.-J.; Xu, T.; Wang, Y.-B.; Lu, X.-B. ACS Macro Lett 2014, 3, 896. doi: 10.1021/mz500437y
[21]	Zhang, P.; Zhou, H.; Lu, X.-B. Macromolecules 2019, 52, 4520. doi: 10.1021/acs.macromol.9b00652
[22]	Zhao, W.; Wang, Q.; He, J.; Zhang, Y. Polym. Chem. 2019, 10, 4328. doi: 10.1039/C9PY00626E
[23]	Bai, Y.; He, J.; Zhang, Y. Angew. Chem. Int. Ed. 2018, 57, 17230. doi: 10.1002/anie.v57.52
[24]	Weiss, C. J.; Marks, T. J. Dalton Trans. 2010, 39, 6576. doi: 10.1039/c003089a
[25]	Xu, T.; Chen, E. Y.-X. J. Am. Chem. Soc. 2014, 136, 1774. doi: 10.1021/ja412445n
[26]	Hu, L.; He, J.; Zhang, Y.; Chen, E. Y.-X. Macromolecules 2018, 51, 1296. doi: 10.1021/acs.macromol.7b02647
[27]	Hu, L.; Zhao, W.; He, J.; Zhang, Y. Molecules 2018, 23, 665. doi: 10.3390/molecules23030665
[28]	Bai, Y.; Wang, H.; He, J.; Zhang, Y. Polym. Chem. 2021, 12, 5548. doi: 10.1039/D1PY00924A
[29]	Baskaran, D. Prog. Polym. Sci. 2003, 28, 521. doi: 10.1016/S0079-6700(02)00083-7
[30]	Zhang, Z.-H.; Wang, X.; Wang, X.-J.; Li, Y.; Hong, M. Macromolecules 2021, 54, 8495. doi: 10.1021/acs.macromol.1c01356
[31]	Zhang, Z.-H.; Wang, X.; Weng, B.; Zhang, Y.; Zhang, G.; Hong, M. ACS Polym. Au 2022, 2, 266. doi: 10.1021/acspolymersau.2c00001
[32]	Zhang, Z.-X.; Wu, X.-Y.; Hong, M. Acta Polymerica Sinica 2022, 53, 1150. (in Chinese)
	(张振兴, 吴小余, 洪缪, 高分子学报, 2022, 53, 1150.)
[33]	Beyer, V. P.; Kim, J.; Becer, C. R. Polym. Chem. 2020, 11, 1271. doi: 10.1039/C9PY01571J
[34]	Bates, F. S.; Hillmyer, M. A.; Lodge, T. P.; Bates, C. M.; Delaney, K. T.; Fredrickson, G. H. Science 2012, 336, 434. doi: 10.1126/science.1215368
[35]	Bai, Y.; Wang, H.; He, J.; Zhang, Y. Angew. Chem. Int. Ed. 2020, 59, 11613. doi: 10.1002/anie.v59.28
[36]	Wan, X.-H. Acta Polymerica Sinica 2020, 51, 569. (in Chinese)
	(宛新华, 高分子学报, 2020, 51, 569.)
[37]	Engelis, N. G.; Anastasaki, A.; Nurumbetov, G.; Truong, N. P.; Nikolaou, V.; Shegiwal, A.; Whittaker, M. R.; Davis, T. P.; Haddleton, D. M. Nat. Chem. 2017, 9, 171. doi: 10.1038/nchem.2634
[38]	Gody, G.; Maschmeyer, T.; Zetterlund, P. B.; Perrier, S. Nat. Commun. 2013, 4, 2505. doi: 10.1038/ncomms3505
[39]	Mcgraw, M. L.; Clarke, R. W.; Chen, E. Y.-X. J. Am. Chem. Soc. 2020, 142, 5969. doi: 10.1021/jacs.0c01127
[40]	Li, C.; Zhao, W.; He, J.; Zhang, Y.; Zhang, W. Angew. Chem. Int. Ed. 2022, 61, e202202448. doi: 10.1002/anie.v61.24
[41]	Bai, Y.; Wang, H.; He, J.; Zhang, Y.; Chen, E. Y.-X. Nat. Commun. 2021, 12, 4874. doi: 10.1038/s41467-021-25069-6
[42]	Wan, Y.; He, J.; Zhang, Y.; Chen, E. Y.-X. Angew. Chem. Int. Ed. 2022, 61, e202114946. doi: 10.1002/anie.v61.8
[43]	Reilly, L. T.; Mcgraw, M. L.; Eckstrom, F. D.; Clarke, R. W.; Franklin, K. A.; Chokkapu, E. R.; Cavallo, L.; Falivene, L.; Chen, E. Y.-X. J. Am. Chem. Soc. 2022, 144, 23572. doi: 10.1021/jacs.2c10568 pmid: 36521036
[44]	Wan, Y.; He, J.; Zhang, Y. Angew. Chem. Int. Ed. 2023, 62, e202218248. doi: 10.1002/anie.v62.8
[45]	Kametani, Y.; Tournilhac, F.; Sawamoto, M.; Ouchi, M. Angew. Chem. Int. Ed. 2020, 59, 5193. doi: 10.1002/anie.201915075 pmid: 31943523
[46]	Shibata, K.; Kametani, Y.; Daito, Y.; Ouchi, M. J. Am. Chem. Soc. 2022, 144, 9959. doi: 10.1021/jacs.2c02836
[47]	Gerdt, P.; Studer, A. Angew. Chem. Int. Ed. 2022, 61, e202206964. doi: 10.1002/anie.v61.39
[48]	Zhao, W.; Li, F.; Li, C.; He, J.; Zhang, Y.; Chen, C. Angew. Chem. Int. Ed. 2022, 60, 24306. doi: 10.1002/anie.v60.45
[49]	Wang, X.; Hong, M. Macromolecules 2020, 53, 4659. doi: 10.1021/acs.macromol.0c00553
[50]	Zhou, Y.; Jiang, S.; Xu, X. Chin. J. Chem. 2020, 39, 149. doi: 10.1002/cjoc.v39.1
[51]	Guan, Z. Chem. Asian. J. 2010, 5, 1058. doi: 10.1002/asia.v5:5
[52]	Doi, Y.; Matsubara, K.; Ohta, Y.; Nakano, T.; Kawaguchi, D.; Takahashi, Y.; Takano, A.; Matsushita, Y. Macromolecules 2015, 48, 3140. doi: 10.1021/acs.macromol.5b00076
[53]	Gambino, T.; Martínez De Ilarduya, A.; Alegría, A.; Barroso-Bujans, F. Macromolecules 2016, 49, 1060. doi: 10.1021/acs.macromol.5b02687
[54]	Hosoi, Y.; Takasu, A.; Matsuoka, S.-I.; Hayashi, M. J. Am. Chem. Soc. 2017, 139, 15005. doi: 10.1021/jacs.7b06897
[55]	Oga, Y.; Hosoi, Y.; Takasu, A. Polymer 2020, 186, 122019. doi: 10.1016/j.polymer.2019.122019
[56]	Mcgraw, M. L.; Clarke, R. W.; Chen, E. Y.-X. J. Am. Chem. Soc. 2021, 143, 3318. doi: 10.1021/jacs.1c00561
[57]	Zhao, W.; Wang, Q.; He, J.; Zhang, Y. Macromol. Rapid Commun. 2022, 43, e2200088.
[58]	Mcgraw, M. L.; Reilly, L. T.; Clarke, R. W.; Cavallo, L.; Falivene, L.; Chen, E. Y.-X. Angew. Chem. Int. Ed. 2022, 61, e202116303. doi: 10.1002/anie.v61.15
[59]	Song, Y.; He, J.; Zhang, Y.; Gilsdorf, R. A.; Chen, E. Y.-X. Nat. Chem. 2023, 15, 366. doi: 10.1038/s41557-022-01097-7
[60]	Wang, X.-H.; Wan, X.-H. Acta Polymerica Sinica 2023, 54, 409. (in Chinese)
	(王献红, 宛新华, 高分子学报, 2023, 54, 409.)

Lewis酸碱对催化极性烯烃单体精准聚合的研究进展^★

Research Progress in Precision Polymerization of Polar Olefin Monomers by Lewis Pairs^★

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Lewis酸碱对催化极性烯烃单体精准聚合的研究进展★

Research Progress in Precision Polymerization of Polar Olefin Monomers by Lewis Pairs★

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Lewis酸碱对催化极性烯烃单体精准聚合的研究进展^★

Research Progress in Precision Polymerization of Polar Olefin Monomers by Lewis Pairs^★