Iran Oxidized Bitumen

Iran Oxidized Bitumen or blown bitumen is a type of modified bitumen that is produced by blowing hot air into natural bitumen, and this process increases its heat resistance, durability, and hardness. These changes make blown bitumen an ideal option for various applications such as insulation, waterproofing, and even improving the quality of pavement.

In the following, you will learn about the production method, physical and chemical properties, various applications, and benefits of oxidized bitumen, and you will understand why this material has become particularly popular in construction and civil engineering projects, especially in areas with different climatic conditions.

Production Process of Iran Oxidized Bitumen

Oxidized bitumen or blown bitumen is a type of modified bitumen that is produced by blowing hot air into natural or refined bitumen at temperatures between 200 and 300 degrees Celsius. This process causes the oxygen in the air to react with the hydrogen in the bitumen, changing its chemical structure.

The result of this reaction is an increase in molecular weight and the formation of cross-links, which turns the bitumen into a harder and more resistant material. For this reason, oxidized bitumen has more special properties than regular bitumen, such as a higher softening point, higher viscosity, and improved thermal and chemical resistance.

Blown Bitumen Physical and Chemical Properties

Oxidized bitumen is harder and more viscous than regular bitumen and, due to its better polymer structure, exhibits higher resistance to mechanical and thermal stresses. This type of bitumen is more resistant to ultraviolet radiation and atmospheric factors such as rain and temperature changes and prevents premature cracking and deterioration.

Blown bitumen also has a lower permeability coefficient, which increases its effectiveness in insulating and protecting surfaces.

Comparison of blown and non-blown bitumen

1. Production process

Blown bitumen: Produced by blowing hot air (265–300°C) into raw bitumen. This oxidation process makes the molecular chains heavier and polymer.
60/70 bitumen: Obtained directly from crude oil distillation and does not undergo a chemical modification process.

2. Thermal resistance

Blown: Has a high softening point (85–100°C); does not flow summer and tropical areas. –
60/70: Lower softening point (48–54°C); Softens at high temperatures and is prone to rutting on roads.

3. Hardness and flexibility

Blown: Is harder (penetration degree: 15–40); Less deformed under load but becomes brittle in cold weather. –
60/70: Softer (penetration rating: 60–70); has better flexibility in cold weather but deforms under traffic load.

Oxidized Bitumen in the Construction Industry

Oxidized bitumen is used in various industries due to its special characteristics, the most important of which are:

Insulation and waterproofing

One of the most common applications of Iran oxidized bitumen is its use in the production of waterproofing. Oxidized bitumen waterproofing is a type of prefabricated moisture insulation in which oxidized bitumen is used as the main material along with layers of polyester and tissue fibers.

These waterproofing are produced in two types: plain and coated with aluminum foil. The coated type is suitable for surfaces that are not coated after installation, and the plain type is for surfaces on which another coating is applied. Iran Oxidized bitumen waterproofing is widely used in tropical and temperate regions due to its high resistance to water penetration, heat, and weather conditions.

Road Construction and Paving

Although oxidized bitumen is used less than polymer bitumen in road paving, it is sometimes used as an additive in certain asphalts to increase adhesion between layers and increase the durability of the pavement. It is also used to seal old asphalts and improve their resistance to water penetration and cracking. These applications increase the life of the pavement and reduce maintenance costs.