Recently electrically conductive textiles have been of increasing research interest due to their numerous possibilities for application in various fields of activity. These conductive textiles in future will be used in clothing to measure body parameters or in textiles used to protect against electromagnetic shielding. As this is an emerging field, there is still a lack of characterizing and evaluating the performance of these conductive materials. In the scope of this project work, different yarn materials are coated with Polypyrrole and Carbon (Graphite). These layers are applied to realize textile humidity and temperature sensors. Coated yarns are characterized in order to evaluate their behavior when being worn in every-day life. So, Literature study on electro-less coating of textile structures with Polypyrrole and Carbon (Graphite) coating of different yarn materials and Characterization of coated yarns is presented in this project work.
Table of Contents
Chapter I Literature Study
1.1 Coating
1.2 Polypyrrole (PPy)
1.3 Coating of Yarns with Polypyrrole (PPy)
1.4 Carbon
1.5 Graphite
1.5.1 Properties
1.5.2 Applications Carbon (Graphite) Coated Yarns
1.6 Dip Coating
1.7 Electrical Conductivity
1.8 Electrical Resistance
1.9 Plasma Treatment
1.10 Materials Used
Chapter II Coating of Yarns with Polypyrrole
2.1 Polypyrrole (PPy) Coating Procedure
2.1.1 Plasma Treatment
2.1.2 Rinsing
2.1.3 Polymerization
2.1.4 Rinsing
2.1.5 Drying
2.2 Resistance Measurement at different lengths for coating with Polypyrrole
2.3 Resistance Measurement at different lengths for coating with Polypyrrole(PPy)
2.4 Resistance Measurement at different lengths for coating with Polypyrrole(PPy)
2.5 Resistance Measurement at different lengths for coating with Polypyrrole (PPy)
2.6 Optical Microscopic Views
2.7 Electron Microscopic Views
Chapter III Dip Coating of Yarns with Carbon (Graphite)
3.1 Carbon (Graphite) Dip Coating Procedure
3.1.1 Plasma Treatment
3.1.2 Preparation of Solution
3.1.3 Machine Operation:
3.2 Resistance Measurement at different speeds for Dip Coating with Carbon (Graphite)
3.3 Dip Coating of Yarns with Carbon (Graphite)
Chapter IV Characterization of Yarns
4.1 Comparison of Coated and Uncoated Yarns after Polypyrrole Coating
4.2 Comparison of Uncoated and Coated Diameters after Coating with Carbon (Graphite)
4.3 Comparison of Diameters among Yarns after Coating with Carbon (Graphite)
4.4 Comparison of Different Yarn Resistances after Polypyrrole Coating
4.5 Comparison of Different Yarn Resistances after Carbon (Graphite) Dip Coating
Chapter V Results and Discussions
5.1 Conductivity
5.1.1 For Polypyrrole Coating
5.1.2 For Carbon (Graphite) Coating
5.2 Yarn Diameter
5.2.1 For Polypyrrole Coating
5.2.2 For Carbon (Graphite) Coating
Chapter VI Drawbacks
6.1 Limitations of Project Work
Chapter VII Conclusions
7.1 Conclusions
Research Objectives and Core Themes
The primary objective of this project is to investigate the electrical conductivity of synthetic yarns by coating them with electro-active layers, specifically Polypyrrole and Carbon (Graphite), to enable their application as humidity and temperature sensors.
- Coating of synthetic yarns with conductive polymers and carbon materials
- Characterization of coated yarn diameter and electrical resistance properties
- Evaluation of the influence of coating methods (Polymerization and Dip Coating)
- Analysis of the impact of machine speed on coating thickness and conductivity
- Performance assessment for potential use in wearable sensors and smart textiles
Excerpt from the Book
1.1 Coating
A layer of a substance spread over a surface for protection or decoration; a covering layer. Fabrics made of conventional textile materials generally have high electrical resistivity (> 10^10 Ω). Treatment with a conducting polymer lowers the surface resistivity to (1–10^4 Ω). Unfortunately, conducting polymers have a poor level of process ability because of their mechanical and physical properties (e.g. fragility, infusibility and insolubility). These problems have been overcome by deposition of conducting polymer. [11]
Summary of Chapters
Chapter I Literature Study: Provides an overview of coating processes, conducting polymers like Polypyrrole, carbon-based materials, and fundamental electrical concepts relevant to the study.
Chapter II Coating of Yarns with Polypyrrole: Details the specific experimental procedure for applying Polypyrrole coatings to various synthetic yarns and measuring their resistance.
Chapter III Dip Coating of Yarns with Carbon (Graphite): Explains the preparation of graphite solutions and the dip-coating process used to achieve conductivity in yarn samples.
Chapter IV Characterization of Yarns: Presents a comparative analysis of yarn diameters and electrical resistances before and after the application of different coating materials.
Chapter V Results and Discussions: Interprets the experimental findings regarding conductivity and diameter changes, supported by physical laws like Pouillet's and Landau-Levich.
Chapter VI Drawbacks: Outlines the limitations encountered during the project, particularly regarding time constraints and experimental reproducibility.
Chapter VII Conclusions: Summarizes the overall effectiveness of the coating processes and provides recommendations for future research.
Keywords
Coating, polypyrrole, Carbon, Graphite, dip coating, diameter, resistance, conductivity, synthetic yarns, plasma treatment, electrical resistivity, textile sensors, smart textiles, polymer, experimental characterization
Frequently Asked Questions
What is the core focus of this research project?
The research focuses on enhancing the electrical properties of synthetic yarns by applying conductive coatings, aiming to develop materials suitable for humidity and temperature sensing in textiles.
Which materials are primarily used as conductive layers?
The study utilizes Polypyrrole, an organic conductive polymer, and Carbon (Graphite) flakes as the primary coating materials.
What is the ultimate goal of the investigation?
The goal is to characterize the performance of coated conductive yarns to determine their viability for everyday wearable applications and biomechanical monitoring.
Which experimental methods are employed to coat the yarns?
The project employs Vapor Phase Polymerization and Chemical Synthesis for Polypyrrole coating, and the Dip Coating technique for Carbon (Graphite) application.
What aspects of the coated yarns are evaluated in the main body?
The main body examines the changes in physical dimensions, specifically the yarn diameter, and the resulting electrical resistance and conductivity measured across different lengths and machine speeds.
Which key metrics define the conductive performance of the yarns?
Performance is defined primarily by electrical resistance measurements (in MΩ and KΩ) and the increase in diameter resulting from the chemical coating process.
Why is plasma treatment used on the synthetic yarns?
Plasma treatment is applied to improve the low surface energy and poor wettability of the synthetic yarns, which increases their adhesion properties for the coating materials.
How does the coating speed affect the final result in dip coating?
According to the Landau and Levich equation, the withdrawal speed significantly influences the coating thickness, where optimized speeds result in better coating uniformity and conductivity.
What role does the yarn material type play in the coating process?
The study finds that different synthetic fibers have varying levels of chemical uptake and adhesion; for instance, Polyamide (PA) showed higher hydrophobicity and thus lower adhesion compared to other Polyester variants.
- Arbeit zitieren
- Syed Asaduzzaman (Autor:in), 2015, Coating of Yarns with Electro-active Layers, München, GRIN Verlag, https://www.grin.com/document/298648
