Effect of siloxane spacer length on organosilicon bi-quaternary ammonium amphiphiles

- Synthesized organosilicon bi-quaternary ammonium amphiphiles with different length of siloxane chain.
- Product Si8N2Cl2 possessed the largest surface activity and wetting ability.
- With the length of hydrophobic -Si-O- spacer increasing, the CMC values decrease, and the wetting ability greatly improved.
- Possessed high antimicrobial ability against bacteria.
- The cause of antimicrobial ability below the concentration of CMC and above the concentration of CMC is different.