对非离子二氧化和多氧化催化剂进行系统的研究,用于氧化的氧化和聚合
Iris Haug1, Marc Eberhardt2, Udo Krappe2
1Institute of Polymer Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569, Stuttgart, Germany.
Chemistry (Weinheim an der Bergstrasse, Germany)
|May 24, 2024
概括
这项研究探讨了13种非离子酸催化剂用于环氧化聚合,发现预先组织的酸组,就像双衍生物一样,为氧化物和其他环氧化物产生高性能和定量单体转化. 催化剂显示了长期可控寡合化的实际潜力.
科学领域:
- 聚合物化学 聚合物化学
- 催化科学 催化科学
背景情况:
- 酸盐催化是环氧化物聚合的关键技术.
- 非离子催化剂的结构-活性关系仍然不太清楚.
- 了解这些催化剂对于开发高效的聚合过程至关重要.
研究的目的:
- 为了合成和研究13种非离子酸催化剂用于环氧氧化氧化和聚合.
- 建立结构-活性相关性,重点关注链接器的长度,灵活性和多重的功能.
- 在标准和工业相关的链传递剂丰富条件下评估催化剂性能.
主要方法:
- 合成了13种不同的非离子催化剂.
- 使用氧化物 (PO),1-丁氧化物 (BO) 和基基乙烯 (AGE) 的环氧氧化物和聚合物.
- 在典型和链传递剂 (CTA) 丰富的条件下进行选.
主要成果:
- 基的预组织,以二衍生物为例,导致高效的催化剂.
- 在测试的环氧化物中实现了定量单体转化.
- 一种二博催化剂在经过重复的单体添加后,在数周内表现出持续的活动,产生了明确的基乙烯.
结论:
- 具有预先组织结构的非酸催化剂为高效的环氧化物聚合提供了方便的途径.
- 持续的活动和控制强调了这些催化剂在大规模生产中的实际应用.
- 没有共同启动的对离子是非离子催化剂的潜在优势.
相关概念视频
Olefin Metathesis Polymerization: Overview
2.1K
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...
2.1K
Preparation of Epoxides
7.6K
Overview
Epoxides result from alkene oxidation, which can be achieved by a) air, b) peroxy acids, c) hypochlorous acids, and d) halohydrin cyclization.
Epoxidation with Peroxy Acids
Epoxidation of alkenes via oxidation with peroxy acids involves the conversion of a carbon–carbon double bond to an epoxide using the oxidizing agent meta-chloroperoxybenzoic acid, commonly known as MCPBA. Since the O–O bond of peroxy acids is very weak, the addition of electrophilic oxygen of...
Epoxides result from alkene oxidation, which can be achieved by a) air, b) peroxy acids, c) hypochlorous acids, and d) halohydrin cyclization.
Epoxidation with Peroxy Acids
Epoxidation of alkenes via oxidation with peroxy acids involves the conversion of a carbon–carbon double bond to an epoxide using the oxidizing agent meta-chloroperoxybenzoic acid, commonly known as MCPBA. Since the O–O bond of peroxy acids is very weak, the addition of electrophilic oxygen of...
7.6K
Olefin Metathesis Polymerization: Ring-Opening Metathesis Polymerization (ROMP)
2.6K
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...
2.6K
Acid-Catalyzed Ring-Opening of Epoxides
7.2K
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...
7.2K
Catalysis
26.9K
The presence of a catalyst affects the rate of a chemical reaction. A catalyst is a substance that can increase the reaction rate without being consumed during the process. A basic comprehension of a catalysts’ role during chemical reactions can be understood from the concept of reaction mechanisms and energy diagrams.
26.9K
Base-Catalyzed Ring-Opening of Epoxides
8.4K
Due to their highly strained structures, epoxides can readily undergo ring-opening reactions through nucleophilic substitution, either in the presence of an acid or a base. The nucleophilic substitution reactions in the presence of acid are called acid-catalyzed ring-opening reactions, and nucleophilic substitution reactions in the presence of a base are called base-catalyzed ring-opening reactions. Epoxides undergo base-catalyzed ring-opening reactions in the presence of a strong nucleophile...
8.4K


