Synergistic Modification of Cotton Fabric with Polyamidoamine Dendrimer and Cationic Gemini Surfactant for Enhanced Functional Performance

This study investigates a novel and synergistic approach to functionalize cotton fabric using a second-generation Polyamidoamine (PAMAM) dendrimer and a cationic Gemini surfactant. The modification was efficiently carried out via the pad-dry-cure method using various concentrations of the two agents. The optimal treated fabric was identified through a comprehensive staining test utilizing model anionic (C.I. Acid Red 1) and cationic (C.I. Basic Blue 9) dyes.

The optimal sample demonstrated significant improvements in dyeing performance, showing a 500% increase in color strength with the anionic dye (AR1) and a 27.6% increase with the cationic dye (BB9), confirming successful surface charge modification. Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy confirmed the effective incorporation of both the dendrimer and Gemini compounds onto the cotton surface.

Beyond dyeing, the modified fabric exhibited remarkable functional and mechanical enhancements. Stress-strain analysis revealed a significant 50% increase in elongation compared to raw cotton. Complete inhibition (100\% reduction) was achieved against both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. Furthermore, After 10 washing cycles (Standard Test Method Two), the modified fabric retained substantial activity, maintaining a 60% reduction against S. aureus and a 70% reduction against E. coli.

These results highlight the powerful synergistic effect of the PAMAM dendrimer and Gemini surfactant, establishing a straightforward method for producing cotton textiles with combined superior dyeing affinity, potent durable antimicrobial activity, and improved mechanical flexibility.