第一次合成甲树脂体连接体和结构研究
1Department of Chemistry, Faculty of Science & Technology, Keio University, Yokohama 223-8522, Japan.
Journal of the American Chemical Society
|July 18, 2001
概括
合成了新的树突型多聚胺 (DPAs),表现出高热稳定性和可溶性. 这些pi-结合分子形成球状结构,为先进的材料应用提供了潜力.
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:
- 传统的线性聚乙 (PPA) 具有较差的溶解性,限制了它们的应用.
- 与线性聚合物相比,登德里米尔具有独特的结构和可溶性优势.
研究的目的:
- 合成具有改进性质的新型树突型多烯酸甲 (DPAs).
- 描述这些DPA的结构,热稳定性和可溶性.
- 为了研究DPA分子的自我组装和形状刚性.
主要方法:
- 通过脱水芳基与芳胺使用 (IV) 四化物进行融合合成.
- 使用凝浸透色谱 (GPC),NMR光谱,传输电子显微镜 (TEM),原子力显微镜 (AFM) 和pi-A测量的表征.
- DPA 的晶体结构分析 G2.
主要成果:
- 成功合成了高达第四代 (DPA G4) 的 DPA.
- DPA G4表现出高热稳定性 (Td(10%) = 521 °C) 和在常见有机溶剂中具有很好的溶解性.
- GPC和分子建模证实了DPA G4 (直径~2.3 nm) 的球状结构.
- TEM,AFM和pi-A测量证实了球状形态和自组装行为.
- 核磁共振研究表明溶液中的形状刚性.
结论:
- 与线性PPA相比,新型DPA具有更高的热稳定性和可溶性.
- 合成的DPA表现出明确的球形结构和自我组装能力.
- 这些发现表明DPA是先进功能材料的有希望的候选者.
相关概念视频
Golgi Matrix Proteins
Golgi matrix proteins are a group of highly dynamic proteins that maintain the stacked structure of Golgi. These proteins adapt to rapid morphological changes of the Golgi during the cell cycle. During cell division, mild proteolysis removes these connections resulting in Golgi unstacking. In The daughter cells, these proteins help reassemble the unstacked Golgi.
One of the first identified Golgi matrix proteins was GM130, a rod-like protein located in the cis-Golgi. Subsequently, many Golgi...
One of the first identified Golgi matrix proteins was GM130, a rod-like protein located in the cis-Golgi. Subsequently, many Golgi...
Animal and Plant Cell Structure
Animal and plant cells not only differ in their structure, function, and mode of nutrition but also in how they reproduce, specialize, and organize into complex structures.
Cell Division
Though both plant and animal cells divide by mitosis (for non-gametic cells) and meiosis (for gametic cells), they differ in the specifics of this process. Unlike animal cells, plant cells lack centrosomes — an organelle responsible for organizing the spindle fibers and segregating the chromosomes during cell...
Cell Division
Though both plant and animal cells divide by mitosis (for non-gametic cells) and meiosis (for gametic cells), they differ in the specifics of this process. Unlike animal cells, plant cells lack centrosomes — an organelle responsible for organizing the spindle fibers and segregating the chromosomes during cell...
Structure of Cadherins
The cadherins were one of the first cell adhesion molecules discovered; the term “cadherins” is based on their calcium-dependent adhering properties. The first cadherins discovered on the epithelial, neuronal, and placental cells were named E-cadherin, P-cadherin, and N-cadherin, respectively. These classical cadherins share sequence and structural similarities. Other cadherins, including those involved in cell signaling, are grouped into non-classical cadherins. This diversity of cadherins...
Cellulose and Pectic Polysaccharides
Every plant cell has a cell wall that protects the cell, provides structural support, and gives the cell shape. Cellulose, the main structural component of the plant cell wall, makes up over 30% of plant matter. It is the most abundant organic compound on earth. Cellulose is an unbranched polysaccharide composed of linear chains of glucose molecules linked by β (1→4) glycosidic bonds.
As a cell matures, its cell wall specializes according to its type. For example, the parenchyma cells of...
As a cell matures, its cell wall specializes according to its type. For example, the parenchyma cells of...
Cell Adhesion in Plants
Plants have rigid cell walls that are made up of cell wall polysaccharides that mediate cell-cell adhesion. The primary cell walls of plants consist of two independent and interacting polysaccharide networks: a pectin matrix that embeds the second network comprising cellulose and hemicelluloses.
Pectins are complex heteropolymers mainly composed of negatively-charged α-D-glucopyranosyl uronic acid and some neutral glycosyl residues such as α-L-rhamnopyranose, α-L-arabinofuranose, and...
Pectins are complex heteropolymers mainly composed of negatively-charged α-D-glucopyranosyl uronic acid and some neutral glycosyl residues such as α-L-rhamnopyranose, α-L-arabinofuranose, and...
Peptidoglycan Synthesis
Structure of PeptidoglycanPeptidoglycan is a vital structural component of the bacterial cell wall, providing mechanical strength and shape to the cell. It consists of repeating units of two sugars—N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM)—linked by β-1,4 glycosidic bonds. These sugar chains are cross-linked by short peptide chains, forming a mesh-like polymer that surrounds the bacterial plasma membrane.Cytoplasmic Phase – Precursor SynthesisPeptidoglycan biosynthesis begins in...


