基于香,基和基双碳酸的全芳香热热性共聚体
Pavel A Mikhaylov1, Kirill V Zuev1, Yaroslav V Golubev1
1A. V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences (TIPS RAS), 29 Leninsky Prospekt, 119991 Moscow, Russia.
Polymers
|June 19, 2024
概括
使用香酸 (VA) 合成的新型共聚合物具有高分子量,玻璃过渡温度约为130°C. 这些热热聚合物具有应用潜力,但需要在280°C以下进行加工.
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
- 有机合成 有机合成
背景情况:
- 芳香聚烯在先进材料中非常重要,因为它们的热和机械性能.
- 探索酸 (VA) 等新型单体可以带来具有量身定制特性的新型聚合物架构.
- 液晶聚合物 (LCP) 提供独特的加工和性能优势.
研究的目的:
- 合成和描述新型的二元和三元共聚合物,其中包含酸 (VA).
- 研究这些新聚合物的热稳定性,液晶性行为和机械性质.
- 评估香草酸作为热热性共聚合物的中产性单体的适用性.
主要方法:
- 通过溶液,化和固态方法合成二元 (VA/HBCA) 和三元 (VA/HBCA/HBA) 合聚合物.
- 使用内在粘度,玻璃过渡温度 (Tg) 确定和热重力测量分析 (TGA) 进行表征.
- 评估液晶性质和机械特性.
主要成果:
- 成功合成了高分子量共聚合物,其高内在粘度和不溶性表明了这一点.
- 酸的加入导致玻璃过渡温度 (Tg) 约为130°C.
- 三级共聚合物表现出热稳定性,在330-350°C时出现体重减轻,在390-410°C时出现5%的质量减轻,并观察到两阶段的热破坏.
- 合成的共聚合物是热热的,表现出阴性液晶秩序.
- 机械性能与半芳香型共聚合物相似,但低于全芳香型.
结论:
- 香酸 (VA) 是一种可行的介质性单体,用于合成热热型全芳和半芳合聚合物.
- 由此产生的共聚合物具有良好的热稳定性和液晶性质.
- 处理温度不应超过280°C以保持聚合物完整性.
相关概念视频
Aromatic Compounds: Overview
10.5K
In general, the term ‘aromatic’ indicates a pleasant smell or fragrance from fresh flowers, freshly prepared coffee, etc. In the early history of organic chemistry, many benzene derivatives were isolated from the pleasant odor oils of the plants. For example, vanillin was isolated from the oil of vanilla, methyl salicylate from the oil of wintergreen, and cinnamaldehyde from the oil of cinnamon. They all had a pleasant odor; hence the name aromatic was given.
In 1825, Faraday...
In 1825, Faraday...
10.5K
Aromatic Hydrocarbon Cations: Structural Overview
2.8K
Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
Removing one hydrogen from the intervening CH2 group...
Removing one hydrogen from the intervening CH2 group...
2.8K
Characteristics and Nomenclature of Copolymers
2.5K
Copolymers are the products obtained from the polymerization of multiple monomer species. So, in a polymer chain itself, there can be multiple repeating units that come from different monomers. The process of synthesizing a polymer from different monomer species is called copolymerization. When two monomers are involved, the polymer is known as a bipolymer. Polymers with three and four monomers are termed terpolymers and quaterpolymers, respectively. Figure 1 depicts the copolymerization of...
2.5K
Types of Step-Growth Polymers: Polyesters
2.2K
The introduction of polyesters has brought major development to the textile industry. The wrinkle-free behavior of polyester blends has eliminated the need for starching and ironing clothes.
Polyesters are commonly prepared from terephthalic acid and ethylene glycol; the crude product is known as poly(ethylene terephthalate) or PET. However, polyesters are synthesized industrially by transesterification of dimethyl terephthalate with ethylene glycol at 150 °C. The two reactants and the...
Polyesters are commonly prepared from terephthalic acid and ethylene glycol; the crude product is known as poly(ethylene terephthalate) or PET. However, polyesters are synthesized industrially by transesterification of dimethyl terephthalate with ethylene glycol at 150 °C. The two reactants and the...
2.2K
Aromatic Hydrocarbon Anions: Structural Overview
2.8K
Neutral hydrocarbons like cyclopentadiene with an odd number of carbon atoms and one intervening CH2 group in the ring are not aromatic. Cyclopentadiene with 4 π electrons does not satisfy the 4n + 2 π electron rule. Additionally, the intervening CH2 group is sp3 hybridized and lacks a vacant p orbital, thereby interrupting the overlap of p orbitals in a continuous manner and preventing the delocalization of π electrons throughout the ring.
Due to the absence of continuous...
Due to the absence of continuous...
2.8K
Thermal 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


