Nanofibre Electrostatic Spinning via Segmented Rod Electrodes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for producing nanofibres through electrostatic spinning face challenges in creating a homogeneous electric field, especially when using non-conductive substrate materials, leading to defects and uneven fibre deposition.
Innovation Solution
A method and device that apply an electric charge of opposite polarity to the substrate material using a corona emitter, ensuring a homogeneous electrostatic field is induced between the active electrode and the substrate, allowing for uniform nanofibre deposition even on non-conductive materials.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a simple sheet-metal or metallic plate collecting electrode is used to create the electrostatic field, then the device complexity is reduced, but the manufacturing precision and homogeneity of nanofibre deposition deteriorate due to non-uniform electric field distribution and corona formation at triple points
Solution Approach 1:
The collecting electrode is segmented into multiple independent rod-shaped elements arranged in a matrix pattern, replacing the simple sheet-metal plate. Each rod acts as an independent electrode unit, allowing the electric field to be distributed uniformly across multiple localized regions rather than creating concentrated high-field areas at triple points, thereby achieving homogeneous nanofibre deposition while maintaining reasonable device complexity
Solution Approach 2:
Instead of using a continuous conducting surface (sheet-metal plate) that creates triple points with the substrate, the invention inverts the approach by using discrete rod-shaped electrodes with finite contact points. This inversion eliminates the triple point problem inherent in continuous surface electrodes, as the rod ends make localized contact with the substrate without creating the harmful triple point geometry
2Productivity
If spinning wires are arranged parallel between two belts and move through polymer solution reservoir, then the productivity is improved, but the reliability of electric field homogeneity deteriorates due to mutual influencing of electric fields from multiple spinning wires with same polarity
Solution Approach 1:
The spinning electrode system is segmented into multiple independent rod-shaped electrodes arranged in a matrix, with each rod having opposite polarity to its neighbors. This segmentation allows multiple spinning zones to operate simultaneously (maintaining productivity) while the alternating polarity pattern prevents mutual electric field interference that would occur with parallel same-polarity wires, ensuring reliable electric field homogeneity in each localized spinning region
Solution Approach 2:
Each rod-shaped electrode in the matrix creates a localized electrostatic spinning zone with its own optimized electric field characteristics. The local quality of each spinning region is maintained independently through the alternating polarity arrangement, allowing homogeneous nanofibre deposition in each zone while the collective array of zones achieves high overall productivity
3Ease of operation
If a conductive endless belt is used as collecting electrode, then the ease of operation is improved, but the manufacturing precision deteriorates due to corona formation at borders and triple points, causing uneven fibre transport to substrate material
Solution Approach 1:
The continuous belt electrode is replaced with discrete rod-shaped collecting electrodes arranged in a matrix that contacts the substrate at multiple localized points. This segmentation eliminates the border and triple point problems inherent in continuous belt electrodes, as each rod creates isolated contact regions without the harmful geometric discontinuities that cause corona discharge and uneven fibre transport, while still allowing easy substrate movement through the rod array
4Productivity
If two spinning electrodes with opposite polarity are arranged against each other with fabric in between, then the productivity is improved, but the reliability of electric field homogeneity deteriorates to the point where the device either does not work or works irregularly for very short period
Solution Approach 1:
The electrode system is segmented into multiple rod-shaped elements arranged in alternating polarity patterns on both sides of the substrate. This segmentation breaks down the complex interaction between large opposite-polarity surfaces into many small, localized spinning zones. Each zone maintains stable electric field conditions independently, preventing the runaway electrical breakdown that occurs in large-scale opposite-polarity configurations, while the collective array achieves high double-sided deposition productivity
Solution Approach 2:
Each rod-shaped electrode creates a localized spinning zone with optimized electric field characteristics independent of its neighbors. The local quality of each zone is maintained through the alternating polarity arrangement, ensuring stable and homogeneous nanofibre deposition in each region. This localized control prevents the electric field instability that plagues large-scale opposite-polarity electrode configurations
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 approach enables reliable and stable production of homogenous nanofibre layers on various substrate materials, including non-conductive ones, by maintaining a consistent electric field and preventing corona formation, thus improving the efficiency and homogeneity of the electrostatic spinning process.
Implementation Method 1
A method and device that apply an electric charge of opposite polarity to the substrate material using a corona emitter
Implementation Method 2
ensuring a homogeneous electrostatic field is induced between the active electrode and the substrate
Implementation Method 3
during which the produced nanofibres deposit on a substrate material passing through the active chamber
Data Source
Figure 1~2
AI summary
Method for production of deposit or layer of nanoparticles or a layer of nanofibres from solutions or melts of polymers in electrostatic field of a high intensity, during which the produced nanoparticles or the produced nanofibres deposit on a substrate material (3) passing through the active chamber (1), in which is positioned the active electrode (2). The electrostatic field for production, transfer and depositing of nanoparticles or production, transfer and depositing of nanofibres is induced between the active electrode (2) and the substrate material (3), on which in the direction of its movement in front of and/or opposite to the active electrode (2) there is applied an electric charge of opposite polarity than that of the active electrode (2), while an electric charge applied on the substrate material (3) is being partially or totally consumed through depositing of nanoparticles or nanofibres on the moving substrate material (3). In the production device there are one opposite to another positioned the active electrode (2) connected to a high voltage source and the substrate material (3) coupled with means for initiating its forward motion. The substrate material (3) is positioned in the active chamber (1) without contact with any charged and/or grounded means while it contains quantity of electrical charge sufficient to induce electrostatic field of a high intensity between the active electrode (2) and substrate material (3).