The secret to soap's impressive might is its hybrid structure. Soap is made of pin-shaped molecules, each of which has a hydrophilic head — it readily bonds with water — and a hydrophobic tail, which shuns water and prefers to link up with oils and fats.

Fibers that like cotton, wool, and linen are naturally hydrophilic, but synthetic fibers such as polyester, acrylic, and modacrylic are naturally hydrophobic and have poor absorbency, so these fibers need help to have an attraction or a love of water, therefore a finish is necessary for hydrophiliciRead more

Ethanol is hygroscopic, gasoline is hydrophobic. Water contamination in fuel can cause engine non-starting and corrosion issues. Ten percent ethanol blends can hold small amounts of water in solution, above this level a phase separation of water and ethanol mix separates from the gasoline.

Shampoos contain SURFace ACTive ageNTS (aka. Surfactants) which have hydrophilic (water-loving heads and hydrophobic (water-hating) tails, where the tails are attracted to and attach to the particles on the hair. The surfactants are rinsed away along with the particles on the hair surface.

Glycerol, also called glycerine. Glycerol is easily soluble in water due to the ability of polyol groups to form hydrogen bonds with water molecules. Glycerol has high dielectric constant 42.5 and is freely miscible with water. So it is hydrophilic.