Oxidized Bitumen 90/15, also known as Blown Bitumen 90/15 or Oxidized Asphalt 90/15, is a semi-solid industrial grade bitumen produced through a controlled air-blowing (oxidation) process applied to petroleum bitumen. During production, a mixture of Vacuum Bottom (VB) and Vacuum Slop (VS) feedstock is subjected to high temperature (typically 200–300°C) and controlled pressure inside the oxidation reactor. In this process, hydrogen atoms within the bitumen molecules react with oxygen from the air, leading to polymerization of higher hydrocarbons. This chemical transformation results in a material with lower penetration and higher softening point compared to the original base bitumen.

Definition and Material Characteristics

Oxidized Bitumen 90/15 is characterized by a softening point around 90°C and a penetration value around 15 (0.1 mm). These properties indicate a hard and thermally stable bitumen grade with excellent resistance to deformation at elevated temperatures. The oxidation process significantly improves the temperature susceptibility of the bitumen, enhancing its stability across a wide thermal range.

This grade exhibits thermoplastic behavior, softening when heated and hardening upon cooling, while maintaining strong adhesion and cohesion. Oxidized Bitumen 90/15 demonstrates no sagging at high temperatures, retains flexibility at lower temperatures, and provides reliable performance in demanding construction and industrial environments.

Physical and Performance Properties

Oxidized Bitumen 90/15 offers the following key characteristics:

• High softening point for superior thermal resistance

• Low penetration indicating hard and stable consistency

• Excellent adhesion to various substrates

• Good resistance to aging and environmental exposure

• Stable performance during repeated heating and cooling cycles

• Strong waterproofing and sealing capability

These properties make this grade suitable for applications requiring dimensional stability, durability, and moisture resistance.

Meaning of Grade 90/15

The designation 90/15 represents:

• A softening point centered around 90°C, measured using the Ring and Ball method according to ASTM D36

• A penetration value around 15 (0.1 mm) at 25°C, measured according to ASTM D5 or IP49

This combination places Oxidized Bitumen 90/15 among hard oxidized bitumen grades used primarily for industrial, waterproofing, and protective applications rather than flexible paving layers.

Applications of Oxidized Bitumen 90/15

Oxidized Bitumen 90/15 is widely used in numerous industrial and construction applications, including:

• Roofing systems and heavy-duty waterproofing

• Bitumen membrane sheets for insulation and isolation

• Pipe coating for corrosion resistance

• Civil engineering and public works structures

• Asphalt-based paints for metal corrosion protection

• Hydraulic applications and Portland cement pavement joints

• Paint, lacquer, and varnish manufacturing

• Adhesives and electrical laminate bonding

• Caulking, mastics, and damp proofing systems

• Synthetic turf base layers

Additionally, this grade is extensively applied in the automotive industry for vehicle undercoating, where it provides excellent waterproofing, dustproofing, corrosion resistance, and noise reduction.

Application Guidelines

Oxidized Bitumen 90/15 should be heated to approximately twice its softening point to achieve proper flow and workable viscosity. Prior to application, all surfaces must be dry, clean, and free from dust, loose particles, curing compounds, slurry, oil, or other contaminants to ensure proper adhesion and performance.

Storage, Handling, and Safety

When stored and handled in accordance with the product MSDS, Oxidized Bitumen 90/15 maintains its quality and performance for up to 10 years, even when subjected to multiple heating and cooling cycles. Proper storage conditions and controlled reheating are essential to preserve material integrity and application safety.

Packaging and Supply

Oxidized Bitumen 90/15 is available in a variety of packaging options to suit different customer and project requirements, including:

• Kraft paper bags

• Meltable plastic bags

• Steel drums

• Bulk supply

The product is manufactured from penetration grade bitumen through a controlled air-blowing process and supplied in full compliance with ASTM standards, ensuring consistent quality and specification conformity.

Technical Specification – Oxidized Bitumen 90/15

Conclusion

Oxidized Bitumen 90/15 is a high-performance hard-grade blown bitumen engineered for waterproofing, insulation, corrosion protection, and industrial construction applications. Its high softening point, controlled penetration, and excellent stability make it an ideal choice for projects requiring long-term durability, thermal resistance, and reliable performance under harsh environmental conditions.