Hydrophobicity Study of Melamine, 1,3,5-Benzenetricarbonitrile, and 1,3,5-Triaminobenzene

The molecular hydrophobicity of melamine (MA), 1,3,5-triaminobenzene (TAB), and 1,3,5-benzenetricarbonitrile (BTCN) was investigated using various methods. Hydrophobicity is influenced by charge distribution, polar functional groups, and solvent interactions. Our findings indicate that at ultralow concentrations, these compounds are fully dispersed in aqueous solutions, with hydrophobicity decreasing in the order MA > TAB > BTCN. Interestingly, when the concentration surpasses a critical threshold, the hydrophobicity order undergoes a complete reversal: BTCN > MA > TAB. This concentration-dependent inversion offers a fundamental theoretical basis for the molecular design of stimuli-responsive hydrophobic materials.