Acta Chimica Sinica ›› 2024, Vol. 82 ›› Issue (2): 213-225.DOI: 10.6023/A23100445 Previous Articles     Next Articles

Special Issue: 庆祝《化学学报》创刊90周年合辑



李雅宁a,b, 王晓艳a,*(), 唐勇a   

  1. a 中国科学院上海有机化学研究所 金属有机化学国家重点实验室 上海 200032
    b 上海科技大学 物质科学与技术学院 上海 201210
  • 投稿日期:2023-10-10 发布日期:2024-01-04
  • 作者简介:

    李雅宁, 上海科技大学/中国科学院上海有机化学研究所2019级联合培养博士. 2019年本科毕业于河南大学. 目前研究方向为光诱导的可控自由基聚合.

    王晓艳, 中国科学院上海有机化学研究所副研究员. 2010年本科毕业于东北林业大学. 2015年在中国科学院长春应用化学研究所取得博士学位. 随后在中国科学院上海有机化学研究所金属有机化学实验室/南开大学化学系进行博士后的研究工作. 2017年正式加入上海有机所金属有机化学国家重点实验室, 开展新型过渡金属催化剂、可控自由基聚合及可控烯烃配位聚合等方面的研究.

    唐勇, 中国科学院上海有机化学研究所研究员. 1986年本科毕业于四川师范大学; 1992年和1996年先后在中国科学院上海有机化学研究所获得硕士和博士学位. 1996年至1999年先后在美国科罗拉多州立大学和美国乔治城大学从事博士后研究; 1999年5月入职上海有机化学研究所, 2000年1月, 担任上海有机化学研究所“百人计划”项目研究员, 2015年当选中国科学院院士. 主要从事金属有机化学和高分子化学研究, 包括: 不对称催化、烯烃聚合催化剂的设计、合成与应用、叶立德化学以及天然产物全合成等.

  • 基金资助:
    中国科学院青年创新促进会(2020259); 国家自然科学基金(22271304); 上海市启明星计划(21QA1411200); 上海市自然科学基金(23ZR1476300)

The Regulation of Stereoselectivity in Radical Polymerization

Yaning Lia,b, Xiaoyan Wanga(), Yong Tanga   

  1. a State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032
    b School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210
  • Received:2023-10-10 Published:2024-01-04
  • Contact: E-mail:
  • About author:
    Dedicated to the 90th anniversary of Acta Chimica Sinica.
  • Supported by:
    Youth Innovation Promotion Association CAS(2020259); National Natural Science Foundation of China(22271304); Shanghai Rising-Star Program(21QA1411200); Shanghai Natural Science Foundation(23ZR1476300)

The physical and chemical properties of polymer strongly depend on the structures of the polymer chain. The structure studies range from the structure of repeat units and their mole fractions to more detailed microstructures, such as molecular weight and its distribution, the sequence of monomer units (block, gradient, alternating, graft, etc.), topology (stars, combs, networks, brushes, etc.), the end-functionalities and tacticity. Among them, the regulation of the polymer tacticity is greatly significant. For example, the stereospecific coordination polymerization of propylene has shown great commercial value. The control of macromolecular structure is difficult for free radical polymerization, although it is one of the most widely used polymerization techniques in the production of polymer materials. The development of reversible deactivated radical polymerization (RDRP) has significantly improved the control over the molecular weight of polymer. However, the regulation of stereoselectivity is extremely challenging for all forms of radical polymerization. One of the reasons is because a terminal carbon of propagating radical takes essentially a neutral sp2 planar-like structure without counter species in contrast to an anionic sp3 pyramidal or cationic sp2 planar-like structure with counter ion or chiral catalyst site. This brings about a non-stereospecific radical propagation, and results in the energy difference between two enantiomers of an active radical species is small and the energy barrier between the enantiomers is low compared to the thermal energy at the polymerization temperature. In this review, the regulation of stereoselectivity in free radical polymerization are comprehensively summarized, evaluated, and prospected from the perspective of regulation strategies, including polymerization in restricted environment, using monomer containing chiral or bulky substituents, solvent (hydrogen bond) effect, the addition of Lewis acid and catalyst or ligand effect. Although these strategies have achieved some preliminary progress, there are still some problems in general, such as limited monomer scope, high solvent cost, complex reaction system, high Lewis acid loading, low catalytic efficiency and insignificant regulatory effect. The use of controlled radical polymerization catalysts to regulate stereoselectivity is of great potential. In the future, the studies on the radical asymmetric catalysis of small molecule can be used for reference to carefully design the structure of the catalyst and optimize the reaction conditions. In this way, the distance between the catalytic center and the terminal radical of the polymer chain is narrowed, and a confined space environment is created to enhance the stereochemical influence of the catalyst structure on the radical addition polymerization process.

Key words: radical polymerization, stereoselectivity, mechanism, tactic polymer, catalyst