How Sealcoating Delays Asphalt Oxidation Process and Prevents Premature Pavement Damage

Sealcoating is an integral part of asphalt maintenance. Asphalt is a commonly used paving material in driveways, parking lots, and roads. It is preferred in constructing road surfaces because it is relatively cheaper to install compared to other materials like concrete blocks. However, when asphalt is laid down, it undergoes chemical changes throughout its lifespan, which can affect its visco-elasticity properties and durability. 

"asphalt contractors applying a sealcoat"

Asphalt pavements have a life expectancy of about 20 to 25 years but this lifespan can be reduced by effects caused by environmental factors like ultraviolet rays, snow, and water. Asphalt paving material used in road construction undergoes an aging process known as oxidative aging. From the time the asphalt is laid down, it starts undergoing oxidation. When examining how environmental and manmade factors affect the quality of asphalt pavements, it is important to consider the asphaltic molecular structure and its changes.

Manmade factors like oil spillage and de-icing salts can also degrade the quality of asphalt pavements. The vulnerability of asphaltic paving material to weather conditions and chemical substances can be reduced by applying a top membrane cover known as sealcoat through the process of asphalt pavement sealcoating.

Asphalt pavement material is made up of aggregate, fillers, and binders such as bitumen, which help in holding together the mixture. Since asphalt pavements will naturally degrade with time, understanding the elements, which speed up the degradation process, can help in putting up preventive measure thus prolonging the life of roads, driveways, and parking lots.

What is sealcoating?
Sealcoating is the application of a weatherproof membrane layer on top of the blacktop of a road surface. A sealcoat is a surface treatment aimed at preventing damages on blacktop caused by things like heat from the sun, moisture, and oil spillage. The sealcoats are made of asphaltic material like emulsions, cutbacks, and paving grade-asphaltic cement and are modified with asphalt liquid mixtures such as latex and polymers.

One thing with asphalt sealcoats is that they only provide a protective barrier and do not cure problems that may exist underneath the pavement such as large cracks and road foundation failure. This means that before a surface treatment is done with use of sealcoats, if there are any damages on pavements and sub-base layer, they should be repaired. Otherwise, the sealcoat may only mask the problems and soon cracks and other deformities on pavements begin to show up again.