Video Experimental Relacionado

Updated: Jan 28, 2026

Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers

Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers

Published on: December 16, 2022

Polímeros supramoleculares lineales impulsados por la dimerización anión-anión de los monómeros de fosfonato

Wei Zhao¹, Bo Qiao¹, Joshua Tropp²

¹Department of Chemistry , Indiana University , 800 East Kirkwood Avenue , Bloomington , Indiana 47405 , United States.

Journal of the American Chemical Society

|February 22, 2019

Resumen

Los investigadores desarrollaron polímeros supramoleculares basados en aniones utilizando interacciones estabilizadas por receptores. Estos nuevos polímeros demuestran una polimerización lineal eficiente y capacidad de respuesta a los estímulos ambientales, abriendo caminos para materiales funcionales.

Área de la Ciencia:

Química supramolecular
Ciencia de los polímeros
Ciencias de los materiales

Sus antecedentes:

Los polímeros supramoleculares aprovechan enlaces reversibles y no covalentes para materiales avanzados.
Los polímeros a base de aniones son escasos debido a las débiles fuerzas de interacción.
Los polímeros supramoleculares existentes a menudo dependen de las interacciones impulsadas por cationes.

Objetivo del estudio:

Introducir un nuevo enlace no covalente para la formación eficiente de polímeros basados en aniones.
Explorar el comportamiento de polimerización de los fosfonatos difuncionales a través de las interacciones anión-anión.
Para demostrar la naturaleza de respuesta a los estímulos de estos nuevos polímeros supramoleculares.

Principales métodos:

Diseño de las interacciones anión-anión estabilizadas por el receptor.
Síntesis y caracterización de los monómeros de fosfonato disfuncionales.
Difracción de rayos X de cristal único para confirmar la estructura del polímero y la estequiometría.
Mediciones de viscosidad y espectroscopia de resonancia magnética nuclear (RMN) para evaluar la polimerización.

Principales resultados:

Se logró una polimerización lineal eficiente de los fosfonatos difuncionales.
La difracción de rayos X de cristal único confirmó una estequiometría 2: 2 entre los grupos finales de fosfonato y los macrociclos de cianostar.
El grado de polimerización aumentó con la flexibilidad del enlace (por ejemplo, C12H24).
Se identificó una concentración crítica de polimerización de 5 mM, correlacionada con los cambios de viscosidad y RMN.
Los polímeros exhibieron dependencia de concentración y respuestas reversibles a ácido, base y aniones competitivos.

Conclusiones:

Se desarrolló con éxito una nueva clase de polímeros supramoleculares basados en aniones.
La interacción anión-anión estabilizada por el receptor proporciona un enlace no covalente robusto para el ensamblaje macromolecular.
Estos polímeros ofrecen una simplicidad de diseño comparable a los polímeros metalo-supramoleculares.
Se espera que los hallazgos avancen en el desarrollo de materiales funcionales a medida basados en aniones.

Más Videos Relacionados

Detection of Viruses from Bioaerosols Using Anion Exchange Resin

Detection of Viruses from Bioaerosols Using Anion Exchange Resin

Published on: August 22, 2018

Author Spotlight: Innovative Techniques for ROS Detection and Implications for Platelet Research

Author Spotlight: Innovative Techniques for ROS Detection and Implications for Platelet Research

Published on: March 29, 2024

Videos de Conceptos Relacionados

Aromatic Hydrocarbon Anions: Structural Overview

Aromatic Hydrocarbon Anions: Structural Overview

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...

Anionic Chain-Growth Polymerization: Overview

Anionic Chain-Growth Polymerization: Overview

The polymerization process that involves carbanion as an intermediate is called anionic polymerization. It is also a type of addition or chain-growth polymerization. Anionic polymerization gets initiated by a strong nucleophile such as an organolithium or a Grignard reagent. The most commonly used initiator for anionic polymerization is butyl lithium. Monomers involved in anionic polymerization must possess a vinyl group bonded to one or two electron-withdrawing groups. For instance,...

Anionic Chain-Growth Polymerization: Mechanism

Anionic Chain-Growth Polymerization: Mechanism

The mechanism for anionic chain-growth polymerization involves initiation, propagation, and termination steps. In the initiation step, a nucleophilic anion, such as butyl lithium, initiates the polymerization process by attacking the π bond of the vinylic monomer. As a result, a carbanion, stabilized by the electron‐withdrawing group, is generated. The resulting carbanion acts as a Michael donor in the propagation step and attacks the second vinylic monomer, which acts as a Michael...

Polymers

Polymers

The word polymer is derived from the Greek words “poly” which means “many” and “mer” which means “parts”. Polymers are long chains of molecules composed of repeating units of smaller molecules, known as monomers. They either occur naturally, such as DNA and proteins, or can be constructed synthetically, like plastics. They have varied structural characteristics, such as linear chains, branched chains, or complex networks, that contribute to the...

π Molecular Orbitals of the Allyl Cation and Anion

π Molecular Orbitals of the Allyl Cation and Anion

An allyl group is a three-carbon conjugated system where the sp³-hybridized allylic carbon is bonded to a CH=CH2 group via a single bond. Allyl anions can be obtained by treating propene with a strong base that can deprotonate methyl groups. Allyl cations are formed as intermediates during substitution reactions involving allylic halides. In both cases, the hybridization of the allylic carbon changes from sp3 to sp2, giving rise to a carbon chain with three sp2-hybridized carbons, each with...

Linear Circuits

Linear Circuits

A linear circuit is characterized by its output having a direct proportionality to its input, adhering to the linearity property, which encompasses the principles of homogeneity (scaling) and additivity. Homogeneity dictates that when the input, also referred to as the excitation, is multiplied by a constant factor, the output, known as the response, is correspondingly scaled by the same constant factor. For instance, if the current is multiplied by a constant 'k,' the voltage likewise...