通过环形尺寸效应来定制乙烯网的可回收性
Vincent Scholiers1, Susanne M Fischer1, Bram Daelman1
1Polymer Chemistry Research group, Centre of Macromolecular Chemistry (CMaC) and Laboratory of Organic Synthesis, Department of Organic and Macromolecular Chemistry, Faculty of Sciences, Ghent University, Krijgslaan, 281-S4, Ghent, 9000, Belgium.
Angewandte Chemie (International ed. in English)
|December 26, 2024
概括
回收热固化材料是一项挑战. 新的动态聚合物网络具有快速交换的乙烯键,可以通过挤出进行再加工,同时保持材料强度.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 可持续材料 可持续材料
背景情况:
- 热固化材料的回收很困难,阻碍了可持续的材料使用.
- 动态共价交叉连接通过将热固体完整性与热塑性可加工性相结合提供了一个解决方案.
- 纤维乙烯链接是常见的,但通常通过转化来交换缓慢.
研究的目的:
- 设计新型的动态聚合物网络,利用乙烯交叉链接.
- 为了提高乙烯债券交换反应的速度.
- 为了获得可再加工的热性材料.
主要方法:
- 动态聚合物网络的合理设计,使用dithiol基单体和脂肪酸衍生的三烯.
- 调查以太债券交换动态.
- 调整汇率,通过调整它们之间的距离来调整其功能.
主要成果:
- 开发了与邻近类乙烯的动态聚合物网络,使债券交换更快.
- 在三个数量级上证明了交换动态的可调性.
- 创建了可通过挤出加工的乙烯交联材料.
- 材料在70°C以下表现出良好的爬行阻力.
结论:
- 快速交换的乙烯网络提供了一条可行的途径,可以重新处理可用的热固化材料.
- 对于这些先进的交联材料,现在可以使用挤出加工.
- 这种方法通过使回收利用成为可能,为可持续的材料解决方案做出贡献.
更多相关视频
相关概念视频
01:16Olefin 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
01:17Thermal Electrocyclic Reactions: Stereochemistry
2.0K
The stereochemistry of electrocyclic reactions is strongly influenced by the orbital symmetry of the polyene HOMO. Under thermal conditions, the reaction proceeds via the ground-state HOMO.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
2.0K
01:13Olefin 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
00:53Olefin Metathesis Polymerization: Acyclic Diene Metathesis (ADMET)
1.9K
Acyclic diene metathesis polymerization or ADMET polymerization involves cross-metathesis of terminal dienes, such as 1,8-nonadiene, to give linear unsaturated polymer and ethylene. As ADMET is a reversible process, the formed ethylene gas must be removed from the reaction mixture to complete the polymerization process.
Similar to cross-metathesis, ADMET also involves the formation of metallacyclobutane intermediate by [2+2] cycloaddition of one of the double bonds of a terminal diene with...
Similar to cross-metathesis, ADMET also involves the formation of metallacyclobutane intermediate by [2+2] cycloaddition of one of the double bonds of a terminal diene with...
1.9K
02:33Preparation and Reactions of Thiols
5.9K
Thiols are prepared using the hydrosulfide anion as a nucleophile in a nucleophilic substitution reaction with alkyl halides. For instance, bromobutane reacts with sodium hydrosulfide to give butanethiol.
5.9K
01:29Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry
4.6K
Diels–Alder reactions between cyclic dienes locked in an s-cis configuration and dienophiles yield bridged bicyclic products.
4.6K