Wang Chaoqun, Xia Jian, Zhang Yuxing, Hu Xiaoqiang, Jian Zhongbao
State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China.
School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei 230026, China.
Natl Sci Rev. 2023 Feb 16;10(7):nwad039. doi: 10.1093/nsr/nwad039. eCollection 2023 Jul.
The degradation of plastics has attracted much attention from the global community. Polyethylenes (PEs), as the most abundant synthetic plastics, are most frequently studied. PE is non-degradable and non-polar because of the sole presence of the pure hydrocarbon components. Concurrent incorporation of both in-chain cleavable and functional groups into the PE chain is an effective pathway to overcome the non-degradable and non-polar issue; however, the method for achieving this pathway remains elusive. Here, we report a strictly non-alternating (>99%) terpolymerization of ethylene with CO and fundamental polar monomers via a coordination-insertion mechanism using late transition metal catalysts, which effectively prevents the formation of undesired chelates originating from both co-monomers under a low CO concentration. High-molecular-weight linear PEs with both in-chain isolated keto (>99%) and main-chain functional groups are prepared. The incorporation of key low-content isolated keto groups makes PEs photodegradable while retaining their desirable bulk material properties, and the introduction of polar functional groups considerably improves their surface properties.
塑料的降解已引起全球社会的广泛关注。聚乙烯（PEs）作为产量最大的合成塑料，是研究最为频繁的对象。由于仅含有纯烃类成分，PE是不可降解且非极性的。将链内可裂解基团和官能团同时引入PE链是克服其不可降解和非极性问题的有效途径；然而，实现这一途径的方法仍不明确。在此，我们报道了一种通过使用后过渡金属催化剂，经由配位插入机理，使乙烯与CO及基本极性单体进行严格非交替（>99%）的三元共聚反应，该反应在低CO浓度下有效防止了源自两种共聚单体的不期望螯合物的形成。制备出了具有链内孤立酮基（>99%）和主链官能团的高分子量线性PEs。引入关键的低含量孤立酮基使PEs具有光降解性，同时保留其良好的本体材料性能，而引入极性官能团则显著改善了它们的表面性能。
