化学交联的酸基凝与聚亚齐里丁:对物理化学性质的影响和有前途的应用
Chaehoon Lee1,2, Giacomo Fiocco2,3, Barbara Vigani4
1Department of Chemistry, University of Pavia, Via Taramelli 12, 27100, Pavia, Italy.
ChemPlusChem
|December 10, 2024
概括
化学交叉连接的-酸水凝 (CA-CHEM) 是使用甲基三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三三 这些增强的凝显示出更好的稳定性和受控的水释放,非常适合敏感表面.
科学领域:
- 生物材料科学 生物材料科学
- 聚合物化学 聚合物化学
- 材料工程 材料工程 材料工程
背景情况:
- 酸生物聚合物具有生物降解性,生物相容性和低毒性,使其适用于各种工业应用.
- -酸水凝是广泛使用的,但可以提高定制的机械和水分性能.
- 化学交叉链接为提高酸盐基水凝的性能提供了机会.
研究的目的:
- 开发具有增强性能的新型化学交联-酸水凝 (CA-CHEM).
- 为了研究甲三[3-(1-亚齐里迪尼尔) 酸盐] (PTAP) 交叉链接对酸盐水凝特性的影响.
- 评估这些新型水凝在受控输送应用中的潜力.
主要方法:
- 通过与不同比例的PTAP反应酸盐合成CA-CHEM凝.
- 使用核磁共振 (NMR) 监测交联反应.
- 使用富里埃变换红外衰减总反射 (FTIR-ATR),扫描电子显微镜 (SEM),热重力测量分析 (TGA) 和机械测试进行了表征.
- 评估水的吸收和释放特性.
主要成果:
- 通过NMR和FTIR-ATR证实了酸盐与PTAP的成功化学交叉链接.
- 在SEM分析中,CA-CHEM凝的孔隙性和网络同质性发生了变化.
- 热重力测量分析和机械测试表明,随着PTAP含量增加 (高达1%w/w),降解稳定性和结构强度得到改善.
- CA-CHEM凝显示出对水的吸收和释放有有效的控制,而CA-CHEM-1显示出最受控制的系统.
结论:
- 与普通藻酸盐水凝相比,开发的CA-CHEM凝具有增强的机械性能和降解稳定性.
- PTAP交叉连接有效地修改了酸盐水凝的网络结构和水资源管理能力.
- 该CA-CHEM-1配方显示出对水溶液的控制输送具有显著的前景,特别是对于历史木制乐器等对水敏感的表面.
相关概念视频
03:05Acid Strength and Molecular Structure
Binary Acids and Bases
In the absence of any leveling effect, the acid strength of binary compounds of hydrogen with nonmetals (A) increases as the H-A bond strength decreases down a group in the periodic table. For group 17, the order of increasing acidity is HF < HCl < HBr < HI. Likewise, for group 16, the order of increasing acid strength is H2O < H2S < H2Se < H2Te. Across a row in the periodic table, the acid strength of binary hydrogen compounds increases with increasing...
In the absence of any leveling effect, the acid strength of binary compounds of hydrogen with nonmetals (A) increases as the H-A bond strength decreases down a group in the periodic table. For group 17, the order of increasing acidity is HF < HCl < HBr < HI. Likewise, for group 16, the order of increasing acid strength is H2O < H2S < H2Se < H2Te. Across a row in the periodic table, the acid strength of binary hydrogen compounds increases with increasing...
02:34Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration
The rate of acid-catalyzed hydration of alkenes depends on the alkene's structure, as the presence of alkyl substituents at the double bond can significantly influence the rate.
01:27Inductive Effects on Chemical Shift: Overview
The protons in unsubstituted alkanes are strongly shielded with chemical shifts below 1.8 ppm. Methine, methylene, and methyl protons appear at approximately 1.7, 1.2 and 0.7 ppm, while the proton signal from methane appears at 0.23 ppm. An electronegative substituent, such as chlorine, withdraws the electron density from the protons, increasing their chemical shift. Progressive substitution of the hydrogens in methane by chlorine shifts the proton signals increasingly downfield, to 3.05 ppm in...
01:25Basicity of Heterocyclic Aromatic Amines
Heterocyclic amines, where the N atom is a part of an alicyclic system, are similar in basicity to alkylamines. Interestingly, the heterocyclic amine having a nitrogen atom as part of an aromatic ring has much less basicity than its corresponding alicyclic counterpart. For this reason, as presented in Figure 1, piperidine (pKb = 2.8) is significantly more basic than pyridine (pKb = 8.8).
01:11Aryldiazonium Salts to Azo Dyes: Diazo Coupling
The reaction of weakly electrophilic aryldiazonium (also called arenediazonium) salts with highly activated aromatic compounds leads to the formation of products with an —N=N— link, called an azo linkage. This reaction, presented in Figure 1, is known as diazo coupling and occurs without the loss of the nitrogen atoms of the aryldiazonium salt. Highly activated aromatic compounds such as phenols or arylamines favor the diazo coupling reaction. The coupling generally occurs at the para position.
01:31Substituent Effects on Acidity of Carboxylic Acids
The acidity of carboxylic acids is influenced by the nature of the substituents bounded to the functional group. The acid strength is determined by the stability of the carboxylate anion—the conjugate base formed by dissociating the corresponding carboxylic acid.