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Cotton Cationization and Dyeing in One Bath: A Short-Process, Salt-Free Approach for Reactive Dyes
Zijian Dai1, Jiao Li1, Zixian Zhang2
1Innovation Center for Textile Science and Technology, Donghua University, Shanghai 200051, China.
Polymers
|August 13, 2026
Summary
This study introduces a sustainable, short-process cationic dyeing method for cotton, significantly reducing water use and eliminating salt pollution. This innovative approach enhances efficiency in textile dyeing while maintaining performance.
Area of Science:
- Textile Chemistry
- Sustainable Materials Science
- Green Chemistry
Background:
- Traditional cotton dyeing methods face challenges with high water consumption and salt pollution.
- Sustainable practices are crucial for the textile industry's environmental impact reduction.
Purpose of the Study:
- To develop a short-process, salt-free cationic dyeing method for cotton.
- To optimize dyeing parameters for improved efficiency and reduced environmental footprint.
Main Methods:
- Utilized 2,3-epoxypropyltrimethylammonium chloride (GTA) for a modified short-process cationic dyeing.
- Investigated key parameters: GTA concentration, NaOH concentration, temperature, time, bath ratio, and holding time.
- Determined optimal conditions for C.I. Reactive Red 195, Reactive Black 5, and Reactive Blue 19.
Main Results:
- Achieved salt-free dyeing with significant water savings by eliminating intermediate drying steps.
- Identified optimal conditions: 40 g/L GTA, 1 g/L NaOH, 90 °C for 50 min modification, 60 °C dyeing, 1:15 bath ratio.
- Observed slight decreases in thermal stability and crystallinity, with no significant change in hydrophilicity post-modification.
Conclusions:
- The developed short-process cationic dyeing method offers substantial time, energy, and water savings.
- This sustainable approach provides comparable dyeing performance to conventional methods.
- Presents a practical and eco-friendly alternative for salt-free cotton dyeing.
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