A diol molecule is a compound that contains two Hydroxyl groups (OH), and these hydroxyl groups are attached to a hydrocarbon chain, which makes the main chain of the compound. In this type of molecule, we can find two intermolecular forces
Between the Carbons and Hydrogens in the hydrocarbon chain we have a Van der Waals force, which is a weak force
In the Hydroxyl groups, we will have a Hydrogen bond, which will be connecting Hydrogens and Oxygens