Carbon Nanotube Dispersion with Dual Dispersants for Viscosity Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing carbon nanotube dispersions face issues with high initial viscosity and significant changes in viscosity over time, leading to poor processability and storage stability, which affect the uniform distribution of conductive materials in electrode slurry compositions and degrade battery performance.
Innovation Solution
A carbon nanotube dispersion is formulated using a combination of a cellulose-based dispersant and a polymer dispersant containing hexafluoropropylene (HFP) as a repeating unit, with a weight ratio of 100:10 to 100:400, to achieve low initial viscosity and minimal viscosity change over time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If a cellulose-based dispersant is applied as a sole dispersant, then the rate of change in viscosity over time is reduced, but the initial viscosity of the dispersion is high
Solution Approach 1:
The patent combines a cellulose-based dispersant with a polymer-based dispersant (containing HFP, acrylonitrile, and/or butadiene units) in a weight ratio of 1:0.1 to 1:0.5. This merging of two different dispersant types creates a synergistic effect where the cellulose-based dispersant provides viscosity stability while the polymer-based dispersant reduces initial viscosity, thereby resolving the contradiction between viscosity stability and processability
Solution Approach 2:
The invention creates a composite dispersant system by combining cellulose-based dispersant and polymer-based dispersant in specific proportions. This composite approach allows the dispersion to benefit from both dispersant types simultaneously - the cellulose component ensures minimal viscosity change over time while the polymer component maintains low initial viscosity for excellent processability
2Stability of the object's composition
If a cellulose-based dispersant and a polymer-based dispersant are applied together, then dispersibility is improved, but both the initial viscosity and the rate of change in viscosity over time increase
Solution Approach 1:
The patent optimizes the weight ratio parameters of the two dispersants, specifically setting the ratio of cellulose-based dispersant to polymer-based dispersant at 1:0.1 to 1:0.5. This precise parameter control ensures that the polymer-based dispersant provides sufficient dispersibility enhancement without adding excessive viscosity, while the cellulose-based dispersant maintains viscosity stability. The controlled parameter range prevents the harmful effect of excessive viscosity increase while maintaining improved dispersibility
Data Source
AI summary
The present invention relates to a carbon nanotube dispersion and a preparation method thereof, wherein the carbon nanotube dispersion includes carbon nanotubes, a first dispersant which is a cellulose-based dispersant, a second dispersant containing hexafluoropropylene (HFP) as a repeating unit, and a solvent, and the carbon nanotube dispersion of the present invention has a low initial viscosity and a low viscosity change rate, and thus, is excellent in storage stability and processability.