dear sir

Both Hydrophobic and Hydrophilic particles are classifications for colloidal fluids stability.

Now Hydrophobic is water and/or solvent-hating particles due to its negative charge of physical and/or chemical root (e.g. metal oxides) and the intensity of this charge decide the hating degree. As a result, this particles are thermodynamically unstable which means that particles will aggregate and settled with time even very slowly.

Now this particles if covered by certain surfactant, less negative or positive charge will dominate the surface area instead of the high negative charge which is still the charge of the particles bulk. This trick will change the behavior of particles surface area in fluid from Hydrophobic to Hydrophilic and become water-loving

Hydrophobic particles + surfactant = Hydrophilic behavior

Now Hydrophilic particles without any surface treatment are usually water-loving due to their ability to hydrate in solution so the particles possess little or not negative charge but plenty positive charge so this property make these particles stable thermodynamically and not settled even after long time (e.g. starch, proteins, hydrated metal oxides).

Now you can disturbed this stability by changing the ability of water to love particles by many means e.g. changing the fluid pH this means the treatment came from fluid side and not form particles it self

Hydrophilic particles + fluid chemistry changes = Hydrophobic behavior

thank you

This can be done rather simple by checking dispersion behaviour in hydrophilic versus hydrophobic media. For a more detailed characterization of surface characteristics you may determine Hansen Solubility Parameter by investigating behaviour in a range of different solvents exhibiting larger variation in their solubility parameter. Problem may occur for highly aggregated/agglomerated nanoparticles with localized polar and apolar domains.

dear sir

Both Hydrophobic and Hydrophilic particles are classifications for colloidal fluids stability.

Now Hydrophobic is water and/or solvent-hating particles due to its negative charge of physical and/or chemical root (e.g. metal oxides) and the intensity of this charge decide the hating degree. As a result, this particles are thermodynamically unstable which means that particles will aggregate and settled with time even very slowly.

Now this particles if covered by certain surfactant, less negative or positive charge will dominate the surface area instead of the high negative charge which is still the charge of the particles bulk. This trick will change the behavior of particles surface area in fluid from Hydrophobic to Hydrophilic and become water-loving

Hydrophobic particles + surfactant = Hydrophilic behavior

Now Hydrophilic particles without any surface treatment are usually water-loving due to their ability to hydrate in solution so the particles possess little or not negative charge but plenty positive charge so this property make these particles stable thermodynamically and not settled even after long time (e.g. starch, proteins, hydrated metal oxides).

Now you can disturbed this stability by changing the ability of water to love particles by many means e.g. changing the fluid pH this means the treatment came from fluid side and not form particles it self

Hydrophilic particles + fluid chemistry changes = Hydrophobic behavior

thank you