Preparation and Self-Assembly Behavior of Hydrogen Bonded Cyclic Phosphazenes

The self-assembly system driven by hydrogen bonding has been widely used in various fields. Two hydrogen-bonded cyclophosphazene derivatives with amino groups (AGHP) and carbonyl groups (CGHP) were synthesized by introducing hydrophobic groups and amino groups and hydrophilic groups and carbonyl groups into cyclophosphazene respectively through nucleophilic substitution. After they were dissolved in oil water two phases, stable emulsion, and self-loading membrane structures were obtained through self-loading behavior. The results indicate that strong hydrogen bonding can be formed between these two cyclic phosphazene derivatives with amino and carbonyl groups. This hydrogen bonding can significantly reduce the interfacial tension between water/oil phases (from around 33 mN/m to below 7 mN/m) and improve the interfacial coverage (which can reach over 80%). Meanwhile, under the hydrogen bonding between amino and carbonyl groups, an amphiphilic self-assembled film was obtained at the water oil interface. Through contact angle testing, it was found that the hydrophilic side of this self-assembled film had a contact angle of 77.5° and the hydrophobic side had a contact angle of 124.8°.