代表性阴离子聚合乙烯基乙烯的受控激素同聚合
在PubMed上查看摘要
概括
此摘要是机器生成的。在水中使用氧化物和特定的基启动剂实现了直接的基性聚合. 这种方法利用结和-π相互作用进行高效的聚合,从而实现可控的基聚化.
科学领域
- 聚合物化学
- 有机合成
背景情况
- 由于潜在的副作用,直接基性聚合乙烯具有挑战性.
- 现有的方法往往需要特定的功能组或苛刻的条件.
研究的目的
- 开发一种易于和高效的直接基聚聚合法,用于乙烯基.
- 研究结和-π相互作用在这种聚合过程中的作用.
主要方法
- 使用热触发的阿佐启动剂 (二甲基2,2′-阿佐) 和氧化进行水悬浮聚合.
- 使用dithiocarbamate可逆添加碎片链转移 (RAFT) 剂进行受控聚合的探索.
主要成果
- 在没有基组的乙烯基乙烯直接基同聚化中实现了几乎完全的转化.
- 证明结和Li+-π相互作用对于抑制副作用反应和促进聚合至关重要.
- 通过使用RAFT剂成功调整了受控聚合的方法.
结论
- 开发的方法提供了在水系统中直接基性聚合乙烯的简单途径.
- 了解结和-π相互作用的相互作用是控制乙烯基乙烯聚合的关键.
- 这种方法为控制的乙烯基乙烯聚合提供了基础,具有更广泛应用的潜力.
相关概念视频
The Claisen rearrangement is a [3,3] sigmatropic rearrangement of allyl vinyl ethers to unsaturated carbonyl compounds. The rearrangement is a concerted pericyclic reaction proceeding via a chair-like transition state.
An aromatic Claisen rearrangement involves the conversion of allyl aryl ethers to an unstable ketone intermediate, which tautomerizes to give ortho-substituted phenols.
However, ortho-substituted allyl aryl ethers exclusively yield para-substituted phenols via two sequential...
The representative heuristic describes a biased way of thinking, in which you unintentionally stereotype someone or something. For example, you may assume that your professors spend their free time reading books and engaging in intellectual conversation, because the idea of them spending their time playing volleyball or visiting an amusement park does not fit in with your stereotypes of professors.
This text is adapted from OpenStax, Psychology. OpenStax...
Overview
Ethers can be prepared from organic compounds by various methods. Some of them are discussed below,
Preparation of Ethers by Alcohol Dehydration
In this method, in the presence of protic acids, alcohol dehydrates to produce alkenes and ethers under different conditions. For example, in the presence of sulphuric acid, dehydration of ethanol at 413 K yields ethoxyethane, whereas it yields ethene at 443 K.
This method is a nucleophilic substitution reaction. The two alcohol molecules...
Structure and Bonding
Ethers are organic compounds with an ether functional group which is characterized by an oxygen atom connected to two — identical or different — alkyl, aryl, or vinyl groups. The C–O–C linkage in dimethyl ether — the simplest ether — has an approximately tetrahedral bond angle of 110.3 degrees. The oxygen atom is sp3- hybridized, with the C–O distance being about 140 pm.
Classification of Ethers
Based on their attached substituent...
Crown ethers are cyclic polyethers that contain multiple oxygen atoms, usually arranged in a regular pattern. The first crown ether was synthesized by Charles Pederson while working at DuPont in 1967. For this work, Pedersen was co-awarded the 1987 Nobel Prize in Chemistry. Crown ethers are named using the formula x-crown-y, where x is the total number of atoms in the ring and y is the number of ether oxygen atoms. The term 'crown' refers to the crown-like shape that these ether molecules...
Overview
An ether molecule has a net dipole moment due to the polarity of C–O bonds. Subsequently, boiling points of ethers are lower than those of alcohols of comparable molecular weight and slightly higher than those of hydrocarbons of comparable molecular weight (Table 1).
Ethers can act as hydrogen bond acceptors, making them more water-soluble than hydrocarbons, but since ethers cannot act as hydrogen bond donors, they are much less soluble in water than alcohols. Ethers are considered...

