聚2-基/基-2-沙) - 伊米达复合物作为环氧树脂的热隐性固化剂
Asu Ece Atespare1,2, Taha Behroozi Kohlan1,2, Saeed Salamatgharamaleki1,2
1Integrated Manufacturing Technologies Research and Application Center & Composite Technologies Center of Excellence, Sabanci University, Istanbul, Turkey, 34906.
ACS omega
|September 2, 2024
概括
这项研究开发了新型的多沙林 - 伊米达 (POZ-Im) 热隐性固化剂 (TLCs) 用于单元环氧树脂 (OCERs). 这些TLC增强了OCER的稳定性,控制了固化温度,提供了更好的保质期和性能.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
背景情况:
- 一组件环氧树脂 (OCER) 需要稳定,热潜伏的固化剂以进行受控的应用.
- 传统的固化剂可能会导致过早反应,减少保质期和可用性.
研究的目的:
- 开发和描述基于多克萨林 - 伊米达 (POZ-Im) 的新型热隐性固化剂 (TLC).
- 研究POZ特性和POZ/Im比对OCER固化行为,稳定性和保质期的影响.
主要方法:
- 通过离子环开放聚合 (CROP) 合成POZ同聚合物.
- 通过在POZ矩阵中捕获伊米达来制备POZ-Im TLC.
- 使用DGEBA和POZ-Im TLCs制定OCER.
- 使用FTIR,TGA,DSC (动态和异热) 和光学显微镜进行表征.
主要成果:
- POZ-Im复合体表现出有效的热延迟和受控的伊米达释放.
- 较高的POZ/Im比率和较低的POZ摩尔质量增加了左极限固化温度.
- 优化的OCER表现出更好的保质期,估计在20°C下,特定配方的保质期为15.3天.
- POZ和DGEBA之间的兼容性显著影响了TLC分散和伊米达释放.
结论:
- POZ-Im复合体是有效的新型TLC,用于开发稳定的OCER.
- POZ属性 (摩尔质量,悬挂组) 和POZ/Im比率对于调整固化行为和热延迟至关重要.
- 在OCER系统中,材料兼容性是实现最佳分散和受控固化的关键.
相关概念视频
03:00Preparation of Epoxides
7.5K
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...
7.5K
02:38Structure and Nomenclature of Epoxides
6.3K
Cyclic ethers are heterocyclic compounds with an oxygen atom in the ring along with carbon atoms. They are named depending on the number of carbon atoms present in their ring system. Cyclic ethers with a three-membered ring system are called “oxirane”, four-membered ring systems as “oxetane”, five-membered ring systems as “oxolane”, and six-membered ring systems as “oxane”. The cyclic structure of these rings imposes angle strain, and this strain...
6.3K
01:16Aldehydes and Ketones with Amines: Imine and Enamine Formation Overview
4.5K
Primary amines react with carbonyl compounds—aldehydes and ketones—to generate imines. Imines consist of a C=N double bond and are named Schiff bases after its discoverer—the German chemist Hugo Schiff. On the other hand, secondary amines react with carbonyl compounds to give enamines. In enamines, the presence of a C=C double bond adjacent to the nitrogen atom leads to the delocalization of the lone pair.
4.5K
01:16Cycloaddition Reactions: MO Requirements for Thermal Activation
3.5K
Thermal cycloadditions are reactions where the source of activation energy needed to initiate the reaction is provided in the form of heat. A typical example of a thermally-allowed cycloaddition is the Diels–Alder reaction, which is a [4 + 2] cycloaddition. In contrast, a [2 + 2] cycloaddition is thermally forbidden.
3.5K
01:23Aldehydes and Ketones with Amines: Imine Formation Mechanism
5.4K
Imine formation involves the addition of carbonyl compounds to a primary amine. It begins with the generation of carbinolamine through a series of steps involving an initial nucleophilic attack and then several proton transfer reactions. The second part includes the elimination of water, as a leaving group, to give the imine.
Imines are formed under mildly acidic conditions. A pH of 4.5 is ideal for the reaction.
If the pH is low or the solution is too acidic, the reaction slows down in the...
Imines are formed under mildly acidic conditions. A pH of 4.5 is ideal for the reaction.
If the pH is low or the solution is too acidic, the reaction slows down in the...
5.4K
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