乙烯基环丙烷自由基开环聚合研究进展

张东阳; 陈殿峰

doi:10.14133/j.cnki.1008-9357.20221231002

乙烯基环丙烷自由基开环聚合研究进展

doi: 10.14133/j.cnki.1008-9357.20221231002

张东阳,
陈殿峰^,

中国科学技术大学高分子科学与工程系, 合肥微尺度物质科学国家研究中心, 合肥230026

基金项目: 国家自然科学基金（22101273）；安徽省自然科学基金（2108085MB30）

详细信息

作者简介:
张东阳（1989—），男，博士，主要从事可控自由基聚合研究。E-mail：zdyang@ustc.edu.cn

陈殿峰，中国科学技术大学特任教授，博士生导师。2010年毕业于中国海洋大学， 2015年博士毕业于中国科学技术大学化学系，2015～2020年在美国从事博士后研究。2020年11月加入中国科学技术大学独立开展工作，从事新型可控聚合方法的研究。近年来，主持海外高层次人才引进计划青年项目和国家自然科学青年基金等多个项目，在J Am Chem Soc, Angew Chem Int Ed等发表论文20余篇

通讯作者:
陈殿峰，E-mail：cdf@ustc.edu.cn

中图分类号: O63
计量
- 文章访问数: 123
- HTML全文浏览量: 43
- PDF下载量: 27
- 被引次数: 0
出版历程
- 收稿日期: 2022-12-31
- 录用日期: 2023-02-28
- 网络出版日期: 2023-03-07

Advances in Radical Ring-Opening Polymerization of Vinylcyclopropanes

ZHANG Dongyang,
CHEN Dianfeng^,

Hefei National Research Center for Physical Sciences at the Microscale, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China

摘要

摘要: 乙烯基环丙烷（VCP）是重要的环状单体之一，具有典型的高张力三元环结构，在自由基聚合条件下，能够发生1,5-开环及多种环化反应，生成含有2-戊烯等重复单元的复杂聚合物。聚乙烯基环丙烷（PVCP）具有较小的体积收缩率，是重要的修复材料，在临床等多个领域具有潜在应用价值。本文结合近年来的重要成果，梳理了VCP单体自由基开环聚合的发展过程，重点介绍单体结构设计、聚合物结构控制策略以及结构和材料性能之间的关系。最后，对VCP自由基开环聚合研究领域仍然存在的问题和解决方法进行了总结和展望。
- 乙烯基环丙烷 /
- 体积收缩 /
- 自由基聚合 /
- 开环聚合 /
- 可见光催化
Abstract: Vinylcyclopropane (VCP), one of the most important cyclic monomers, features a highlystrained three-member ring bearing high strain energy, which leads to feasible 1,5-ring-opening process and other transformations under radical conditions, producing polymers with complex chemical structures including the 2-pentenyl repeat unit. Poly(vinylcyclopropane) (PVCP) often exhibits minimal volume shrinkage even volume expansion and can be used as excellent restorative materials with potential clinical applications. In fact, the free radical polymerization technique facilitates rapid and high-yielding polymerizations of a wealth of VCP monomers with diverse chemical structures, affording corresponding high molecular weight polymers, albeit with uncontrolled mixed repeat units. To selectively access the microstructures of PVCP, the merge of VCP chemistry and modern synthetic strategies, including atom transfer radical polymerization and visible-light photoredox catalysis, have extended the radical ring-opening polymerization (rROP) of VCP to new domains. This review provides a comprehensive overview of the development of the rROP for VCP, focusing on monomer design, strategies to tailor the polymeric structures, and the structure-property relationship. In closing, we offer our perspective on its future development based on the challenges still facing the rROP of VCP.
- vinylcyclopropane /
- volume shrinkage /
- radical polymerization /
- ring-opening polymerization /
- visible-light photoredox catalysis

HTML全文

图 1 （a）VCP的结构特点^[5]；（b）丁二烯合成VCP^[7]；（c）烯丙基化途径合成VCP及其衍生官能化^[8]

Figure 1. (a) Orbitals in VCP^[5]; (b) Butadiene routes for VCP synthesis^[7]; (c) Allylic alkylation route for VCP synthesis and further derivatizations^[8]

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图 2 （a）C1-取代基效应^[10-12]；（b）C1单取代VCP的自由基开环聚合^[6]；（c）C1二取代VCP的自由基开环聚合^[8]；（d）C1螺缩酮VCP的自由基开环聚合^[7,15,16]

Figure 2. (a) C1-substituents effects on polymerizability^[10-12]; (b) 1,5-Radical ring-opening polymerization of C1-monosubstituted VCP^[6]; (c) 1,5-Radical ring-opening polymerization of C1-disubstituted VCP^[8]; (d) Radical-ring opening polymerization of C1-spiroketal VCP^[7,15,16]

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图 3 （a）取代基效应对聚合体积收缩效应的影响；（b）S_L和聚合体积收缩效应的关系^[2,8,19-21]

Figure 3. (a) Substituents effects on polymerization volume change; (b) Correlation of S_L value and polymerization volume change^[2,8,19-21]

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图 4 （a）含硅乙烯基环丙烷单体及其自由基开环聚合^[22]；（b）其他官能化VCP单体^[24-29]

Figure 4. (a) Radical ring-opening polymerization of silyl-containing VCP^[22]; (b) Selected examples of functionalized VCP^[24-29]

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图 5 基于单体侧链氢键的聚合加速效应：（a）酯键连接的氢键效应^[31]；（b）酰胺键连接的氢键效应^[32]

Figure 5. Accelerating radical ring-opening polymerization by side-chain hydrogen bonds: (a) ester-linked side chains^[31]; (b) amide-linked side chains^[32]

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图 6 （a）基于侧链活性五氟苯酯的胺酯交换后修饰^[25,35-37]；（b）基于主链C=C双键的双官能化后修饰^[38]

Figure 6. (a) Aminoesterifications of side-chain pentafluorophenyl esters^[25,35-37]; (b) Difunctionalizations of main-chain C=C double bonds^[38]

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图 7 （a）温度响应PVCP的合成^[41]；（b）PVCP溶液透明度（τ）-温度曲线（λ=600 nn）^[41]

Figure 7. (a) Synthetic routes to thermoresponsivePVCP^[41]; (b) Transmittance (τ) as a function of temperature for PVCP aqueous solution (λ=600 nn)^[41]

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图 8 PEG侧链型PVCP的（a）结构及其（b）LCST温度响应曲线^[42]

Figure 8. (a) PEG side-chain containing PVCP and (b) its LCST thermoresponsive character^[42]

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图 9 新型VCP单体和交联剂^[44-49]

Figure 9. Novel VCP monomers and crosslinkers^[44-49]

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图 10 （a）基于Cu-ATRP策略的VCP自由基开环聚合^[50]；（b）有机光催化的VCP自由基开环聚合^[21]；（c）有机光催化的自由基开环聚合机理^[21]

Figure 10. (a) Cu-ATRP strategy in radical ring-opening polymerization of VCP^[50]; (b) Organocatalyzed radical ring-opening polymerization of vinyl cyclopropanes^[21]; (c) Mechanism of organocatalyzed rROP of VCPs^[21]

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图 11 （a）聚合动力学^[21]；（b）光照脉冲实验^[21]（c）聚合物分子量与单体转化率的关系^[21]；（d）嵌段共聚物的合成^[21]

Figure 11. (a) Polymerization kinetics^[21]; (b) Polymerization under pulsed irradiation^[21]; (c) Number-averaged molecular weight as a function of monomer conversion^[21]; (d) Synthesis of chain-extension^[21]

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图 12 （a）基于N,N′-二芳基二氢吩嗪的二维和三维COF材料2D-PN-2-OMe和3D-PN-1^[55]；（b）2D-PN-2-OMe和3D-PN-1的固态紫外-可见光吸收光谱^[55]；（c）2D-PN-2-OMe和3D-PN-1的固态循环伏安曲线^[55]；（d）三线态2D-PN-2-OMe和3D-PN-1的瞬态吸收衰减曲线^[55]；（e）2D-PN-2-OMe和3D-PN-1对单体EtVCP和引发剂M2BP的捕获差异^[55]

Figure 12. (a) Chemical structures of N,N′-diaryl-dihydrophenazine-based COFs, 2D-PN-2-OMe and 3D-PN-1^[55]; (b) Solid-state UV-Vis spectra of 2D-PN-2-OMe and 3D-PN-1^[55]; (c) Solid-state CV curves of 2D-PN-2-OMe and 3D-PN-1^[55]; (d) Transient absorption decay curves of triplet states of 2D-PN-2-OMe and 3D-PN-1^[55]; (e) EtVCP and M2BP uptake of 2D-PN-2-OMe and 3D-PN-1^[55]

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图 13 （a）可见光致氧化还原催化的自由基聚合^[56]；（b）可见光诱导可逆断裂-结合自由基聚合^[56]；（c）五氟苯酯VCP单体的可控自由基开环聚合^[56]；（d）五氟苯酯侧VCP的嵌段共聚^[56]

Figure 13. (a) Photoredox-controlled radical polymerization^[56]; (b) Photoinduced rebound-controlled radical polymerization^[56]; (c) Controlled radical ring-opening polymerization of EtVCP-PFP^[56]; (d) Block copolymerization of EtVCP-PFP^[56]

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图 14 PVCP侧链“氟效应”对聚合物热学和材料性能的响应^[56]

Figure 14. Side-chain fluorine effect of PVCP on its thermal and material properties^[56]

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