单体设计使离子环开放聚合物的机械映射能够对芳香型诺酸盐的聚合物进行映射
Shaoqiu Zheng1, Shu-Sen Chen1, Yang-Yang Li1
1Hefei National Research Center for Physical Sciences at the Microscale and Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui, 230026, China.
Angewandte Chemie (International ed. in English)
|January 22, 2025
概括
研究人员开发了一种新方法,使用一种新型的硫黄单体来制造可降解的聚乙烯. 这一突破使得可控聚合成为可能,产生具有可调节性质的先进性材料.
科学领域:
- 聚合物化学 聚合物化学
- 有机合成 有机合成
- 材料科学 材料科学 材料科学
背景情况:
- 可降解的石化聚合物聚合物,如聚乙烯 (PTEs),提供增强的热,机械和光学性能.
- 类环开放聚合 (ROP) 是一种有前途的PTE途径,但面临着挑战,包括催化剂不耐受,链生长控制不佳,缺乏芳香系统.
研究的目的:
- 通过创新的单体设计和机械学研究来解决诺拉克聚合的局限性.
- 开发一种可控和活体聚合方法,用于获取新型PTE.
- 使用BINOL衍生单体的固有体性来创建轴性体PTE材料.
主要方法:
- 合成一种新型的,高度反应性的thionolactone从1.1'-binaphthyl-2,2'-diol (BINOL) 中.
- 研究聚合动力学和热力学.
- 发现和应用二甲基二甲基二碳酸盐作为活体聚合物的受控启动剂.
主要成果:
- 一个新的thionolactone单体的成功合成.
- 确定快速启动对于受控聚合而言至关重要.
- 证明了真正控制和活体聚合的诺.
- 创建具有受控分子量,反体组成和拓学的轴性性PTE.
结论:
- 单体设计是克服蒂奥诺拉克ROP中的挑战的关键.
- 一种新的BINOL衍生型硫诺和一种特定的启动剂使得可控和活体聚合成为可能.
- 这种方法产生了具有可调节特性的先进的轴性性聚乙烯材料.
相关概念视频
Olefin Metathesis Polymerization: Ring-Opening Metathesis Polymerization (ROMP)
2.5K
Ring-opening metathesis polymerization or ROMP involves strained cycloalkenes as starting materials. The mechanism of ROMP proceeds by reacting cycloalkene with Grubbs catalyst to give metallacyclobutane intermediate which undergoes a ring-opening reaction to form new carbene. The new carbene reacts with another molecule of cycloalkene. Repetition of these steps leads to the formation of an unsaturated open-chain polymer product. All these steps are reversible, however, relieving the ring...
2.5K
Anionic Chain-Growth Polymerization: Overview
2.1K
The polymerization process that involves carbanion as an intermediate is called anionic polymerization. It is also a type of addition or chain-growth polymerization. Anionic polymerization gets initiated by a strong nucleophile such as an organolithium or a Grignard reagent. The most commonly used initiator for anionic polymerization is butyl lithium. Monomers involved in anionic polymerization must possess a vinyl group bonded to one or two electron-withdrawing groups. For instance,...
2.1K
Olefin Metathesis Polymerization: Overview
2.0K
Recently, the development of olefin metathesis polymerization advanced the field of polymer synthesis. Simply put, the reorganization of substituents on their double bonds between two olefins in the presence of a catalyst is known as the olefin metathesis reaction. The use of metathesis reaction for polymer synthesis is called olefin metathesis polymerization.
Ruthenium-based Grubbs catalyst is the most commonly used catalyst for olefin metathesis polymerization. Grubbs catalyst consists...
Ruthenium-based Grubbs catalyst is the most commonly used catalyst for olefin metathesis polymerization. Grubbs catalyst consists...
2.0K
Anionic Chain-Growth Polymerization: Mechanism
2.0K
The mechanism for anionic chain-growth polymerization involves initiation, propagation, and termination steps. In the initiation step, a nucleophilic anion, such as butyl lithium, initiates the polymerization process by attacking the π bond of the vinylic monomer. As a result, a carbanion, stabilized by the electron‐withdrawing group, is generated. The resulting carbanion acts as a Michael donor in the propagation step and attacks the second vinylic monomer, which acts as a Michael...
2.0K
Acid-Catalyzed Ring-Opening of Epoxides
7.1K
Epoxides that are three-membered ring systems are more reactive than other cyclic and acyclic ethers. The high reactivity of epoxides originates from the strain present in the ring. This ring strain acts as a driving force for epoxides to undergo ring-opening reactions either with halogen acids or weak nucleophiles in the presence of mild acid. The acid catalyst converts the epoxide oxygen, a poor leaving group, into an oxonium ion, a better leaving group, making the reaction feasible. The...
7.1K
ortho–para-Directing Activators: –CH3, –OH, –⁠NH2, –OCH3
5.8K
All ortho–para directors, excluding halogens, are activating groups. These groups donate electrons to the ring, making the ring carbons electron-rich. Consequently, the reactivity of the aromatic ring towards electrophilic substitution increases. For instance, the nitration of anisole is about 10,000 times faster than the nitration of benzene. The electron-donating effect of the methoxy group in anisole activates the ortho and para positions on the ring and stabilizes the corresponding...
5.8K


