https://www.khonorwax.com/bitumen-wax.html Generally, wax has negative effects on bitumen. Waxes are melt at the high melting point, that reduces the viscosity of bitumen and influences its high-temperature stability. Wax makes the asphalt binders affinity small, that influence the bonding strength and water resistance of asphalt. At low temperature, the wax crystallizes and precipitate, dispersing in the other components, reducing the contact between the molecules, so that the asphalt is brittle and cracking at low temperature.