Conductive Carbon Black Composites with Non-Conductive Polymer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional electrostatic dissipative materials have a steep percolation curve, leading to a narrow range of filler concentration for achieving desired surface resistivity, making them sensitive to variations in filler loading, which can result in undesirable changes in electrostatic dissipative properties.
Innovation Solution
The development of electrostatic dissipative composites comprising a thermoplastic polymer matrix with a filler system consisting of conductive carbon black and ultra-high molecular weight polyethylene, which forms a continuous conductive network at a critical loading, providing a flat percolation curve and maintaining surface resistivity within the range of 10^6 to 10^9 ohms per square.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional conductive carbon black filled thermoplastic resin is used, then electrostatic dissipative properties are achieved, but the percolation curve is steep resulting in narrow filler concentration range and high sensitivity to variations
Solution Approach 1:
The patent applies composite materials by combining conductive carbon black with non-conductive polymer particles (such as polyethylene, polypropylene, or styrene-butadiene rubber) within the thermoplastic resin matrix. This composite filler system creates a more gradual percolation curve, allowing the material to maintain electrostatic dissipative properties (surface resistivity between 10^6 to 10^9 ohms/sq) over a broader range of filler concentrations, thereby reducing sensitivity to manufacturing variations in filler loading.
2Reliability
If filler concentration is increased to ensure electrostatic dissipative properties, then reliability improves, but material properties and processing characteristics deteriorate
Solution Approach 1:
The patent utilizes parameter changes by introducing non-conductive polymer particles with specific size ranges (0.1 to 10 micrometers) and controlling their concentration (1 to 20 parts by weight per 100 parts of thermoplastic resin). These parameter adjustments allow the formation of a percolation network at lower overall filler concentrations, maintaining electrostatic dissipative properties while preserving better processing characteristics and material properties compared to high filler loading conventional systems.
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
This solution results in robust electrostatic dissipative composites that are less affected by minor changes in filler composition or distribution, offering improved mechanical, thermal, and morphological properties while maintaining consistent surface resistivity across a wider range of conditions.
Implementation Method 1
conductive carbon black and a non-conductive polymer... forms a continuous conductive network at a critical loading, providing a flat percolation curve and maintaining surface resistivity within the range of 10^6 to 10^9 ohms per square
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present disclosure relates to thermoplastic electrostatic dissipative (ESD) composites. The disclosed compositions comprise a thermoplastic resin phase and a filler composition comprising a conductive carbon black and a non-conductive polymer, dispersed within the thermoplastic resin phase. Also disclosed are methods for the manufacture of the disclosed composites and articles of manufacture comprising same.