PBI Ionic Liquid Composite Film With Radiation Cross-Linking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for preparing ionic liquid/polymer composite films, particularly with polybenzimidazole (PBI) as the base material, face challenges such as weak binding forces leading to ionic liquid leakage, instability, and low proton transport efficiency, making them unsuitable for industrial-scale production.
Innovation Solution
A method involving uniform mixing of PBI with unsaturated double bond-containing ionic liquid monomers in a solvent, followed by film formation and ionizing radiation to induce polymerization and cross-linking, creating a physical entanglement between polyionic liquid and polymer chains, thereby fixing the ionic liquid within the composite film.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If an ionic liquid is constructed into a proton transport channel to improve conductivity, then the conductivity of the ionic exchange film is improved, but the binding force between ionic liquid monomer and PBI is weak leading to ionic liquid leakage
Solution Approach 1:
The patent combines PBI polymer with ionic liquid monomers to create a composite film structure where the ionic liquid is embedded within the polymer matrix. This composite approach allows the ionic liquid to provide proton transport channels for improved conductivity while the polymer matrix provides structural support and binding sites to prevent leakage, thus resolving the contradiction between conductivity and stability.
Solution Approach 2:
The patent modifies the ionic liquid monomer structure by introducing unsaturated double bonds that can undergo polymerization. This parameter change in the chemical structure allows the ionic liquid to form covalent bonds with the PBI polymer through radiation-induced polymerization, significantly strengthening the binding force and preventing leakage while maintaining the proton transport capability.
2Stability of the object's composition
If a cross-linking agent is added to induce cross-linking reaction at high temperature, then the ionic liquid is bound to polymer through covalent cross-linking preventing loss, but the process complexity increases
Solution Approach 1:
The patent removes the cross-linking agent from the system and instead uses radiation energy (electron beam or gamma radiation) to directly induce polymerization and cross-linking of the ionic liquid monomers. This extraction of the chemical cross-linking agent simplifies the overall process by eliminating the need for additional chemicals and their associated handling, storage, and removal steps.
Solution Approach 2:
The patent replaces the chemical mechanism (cross-linking agent-mediated cross-linking) with a physical mechanism (radiation-induced polymerization). By using electron beam or gamma radiation to directly activate the unsaturated double bonds in the ionic liquid monomers, the process avoids the complexity of chemical cross-linking agents while achieving the same goal of covalent bonding and ionic liquid retention.
3Object-affected harmful factors
If PBI film structure is used to achieve low vanadium permeability, then vanadium permeability is reduced, but proton transport efficiency becomes extremely low due to dense structure
Solution Approach 1:
The patent creates local channels within the dense PBI matrix by incorporating ionic liquid monomers that, after radiation-induced polymerization, form hydrophilic pathways. These local regions with different properties (hydrophilic ionic liquid channels within hydrophobic PBI matrix) allow selective proton transport while maintaining the overall dense structure's ability to block vanadium ions, thus resolving the contradiction between low vanadium permeability and high proton transport efficiency.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The method results in a stable composite film with high ionic liquid retention, improved conductivity, and reduced vanadium permeability, suitable for industrial production and enhancing battery performance.
Implementation Method 1
performing ionizing radiation on the solid-state film, utilizing the ionizing radiation to induce the ionic liquid monomer to form a polyionic liquid and a cross-linked product
Implementation Method 2
induce the ionic liquid monomer to form a polyionic liquid
Implementation Method 3
generating a physical entanglement effect between a polyionic liquid molecular chain and a base material molecular chain to fix an ionic liquid component in the polymer base material
Implementation Method 4
drying to remove the solvent to obtain a solid film
Data Source
AI summary
Disclosed is a preparation method for an ionic liquid/polymer composite film including uniformly mixing a base material with an unsaturated double bond-containing ionic liquid solution by a good solvent to obtain a casting solution, wherein the base material includes at least one of polybenzimidazole and a polybenzimidazole derivative; flatly laying the casting solution on a substrate, and drying to remove the solvent to obtain a solid film; and performing ionizing radiation on the solid film to generate polymerization/cross-linking by inducing induce the ionic liquid and entangle a polyionic liquid molecular chain with a polymer molecular chain in the base material to fix the ionic liquid in the base material to form a composite film. An ionic liquid/polymer composite film and an application thereof is also disclosed.