Salt crystals are only weakly associated by ionic bonds. The salt ions are more strongly attracted to water than to each other. Spheres of hydration form as water molecules orient around charged particles released from the salt crystals. This prevents the easy recruitment of these water molecules into a crystal lattice of ice. Salt water does not freeze at 0deg.
Some substances have no polarized or charged regions.
They are hydrophobic . Hydrophobic materials do not dissolve in water, and do not become involved in hydrogen bonds.