FAQ: How Oxidized Bitumen is Manufactured & Its Application

🔍 What is oxidized bitumen and how is it different from regular bitumen?

🛢️ Oxidized bitumen, or Blown asphalt, is created by blowing air through hot bitumen, making it more rigid and heat-resistant.

🔥 Unlike regular bitumen, it has a higher softening point and lower penetration value, making Blown asphalt suitable for industrial applications such as roofing and sealing. Its chemical stability also improves its resistance to aging and environmental stress.

🔧 How is oxidized bitumen manufactured?

🏭 The process starts by heating standard bitumen to 240°C–300°C. Then, air is blown through it using a controlled air flow system.

🌬️ This initiates a chemical reaction that modifies the molecular structure, increasing viscosity and creating a more durable and elastic material suitable for high-performance uses like pipe coating and insulation.

🧪 What physical changes occur during oxidation of bitumen?

🧬 During oxidation, the bitumen’s viscosity increases, and it develops a higher softening point with reduced penetration. These changes result from polymerization and dehydrogenation reactions.

🌡️ The modified bitumen becomes more rigid, heat-resistant, and less adhesive—perfect for high-temperature or waterproofing applications.

🏗️ What are the main industrial applications of Blown asphalt?

🧱 Blown asphalt is used in roofing felt, damp proof membranes, pipe coatings, sealants, and expansion joints. It is also applied in cable insulation, adhesives, and chemical tank linings. Its durability and resistance to water and chemicals make it essential in construction, infrastructure, and industrial maintenance sectors.

♻️ Is oxidized bitumen safe for the environment?

🧤 Blown asphalt is stable and non-volatile in its applied form, posing minimal environmental risk. However, safety precautions are needed during manufacturing due to potential fume emissions.

When installed correctly, it offers long-term durability, reducing the need for frequent replacements and contributing to sustainable construction practices.

🌨️ Can oxidized bitumen be used in cold climates?

❄️ While Blown asphalt excels in hot environments, it may become brittle in extreme cold. To enhance flexibility in freezing conditions, it’s often modified with polymers or applied with reinforcement materials.

These adjustments allow it to perform effectively in both warm and cold regions when properly formulated and applied.