What is Oxidized Bitumen?

Definition of Oxidized Bitumen

Generally, Oxidized bitumen or Blown asphalt constitutes one of the foremost cheap film-forming materials to use in coating compositions and has found widespread use in various sorts of paints, cement, pipe coatings, metal primers, and similar compositions. Oxidized Bitumen is a type of bitumen that obtains from blowing air to pure bitumen. It has a lower penetration grade and more softening point in comparison to pure bitumen.
Based on its softening point and penetration grade it classifies into three types low, medium, and hard oxidized bitumen.

The performance of oxidized bitumen plays a crucial role in its successful application across various industries. This part aims to explore the key factors that influence the performance of oxidized bitumen and provides strategies to enhance its overall performance. By understanding these factors and implementing effective strategies, users can achieve superior performance and optimize the utilization of oxidized bitumen.

Blown Bitumen is manufactured by blowing air through bitumen. Specifically, in the air-blowing method of bitumen production, the air at 190 to 200 c is blown to the substance, and the oxidized or air-blown asphalt is produced. Among the unique specifications of Oxidized Bitumen are flexibility, increased durability, and resistance to water.
Oxidized Bitumen is a peculiar amorphous material that is generally in liquid form when discharged by oxidation plants at a temperature ranging from 240°-300°C., and becomes solid or pasty at ambient temperatures. While being relatively hot, it is vicious, whereas when in a pasty or solid-state it possesses a fair degree of elasticity. Both in liquid and in plastic or solid form blown bitumen is a highly insulating material with good adhesion properties with respect to almost any solid material.

Different grades of Oxidized Bitumen:

Oxidized bitumen usage

Blown grade bitumen is widely used as an anti-slip layer compound in the piling industry, for the manufacture of roofing felts, for sound dampening felts, and undercarriage sealant in the automobile industry, electric cable joint protection, joint filling compound, sealant compound, and many others.
Blown asphalt is an aesthetic adhesive substrate for asphalt membranes. Metal and concrete protective coating under atmospheric conditions. Blown asphalt is used for coating pipelines. Blown asphalt is impregnated by a coating of papers and boards. Bonding agent for tiles and mastic also bonding agent for cork plates and adhesive for roofing felts.

Applications of oxidized bitumen in construction

1. Roofing Materials

• Bituminous Membranes: Oxidized bitumen is commonly used in roofing membranes, including bitumen roofing felt. These membranes offer excellent waterproofing and durability.
• Flat Roofs: Its resistance to UV rays and weathering makes it ideal for flat roofing applications where longevity and protection from the elements are crucial.

2. Waterproofing

• Basement Waterproofing: Oxidized bitumen is used in waterproofing systems for basements and foundations. It provides a reliable barrier against moisture infiltration.
• Concrete Protection: It can be applied to concrete structures to prevent water damage and deterioration.

3. Paving and Road Construction

• Asphalt Mixes: Though less common than standard bitumen, oxidized bitumen can be used in specific types of asphalt mixes to enhance performance in certain conditions.
• Repair and Maintenance: It’s also used in road repair and maintenance for its ability to adhere well to existing surfaces and provide a durable finish.

4. Industrial Applications

• Coatings: Oxidized bitumen is used in protective coatings for industrial structures. Its resistance to chemical and environmental factors makes it suitable for harsh conditions.
• Insulation: It can be used in various insulation applications, including thermal and acoustic insulation materials.

5. Waterproofing Membranes for Underground Construction

• Tunnel Linings: In underground construction, such as tunnels and underground facilities, oxidized bitumen membranes are used to provide waterproofing and protect against ground moisture.

6. Gaskets and Sealants

• Construction Sealants: Due to its flexibility and adhesive properties, oxidized bitumen is used in sealants and gaskets for joints and seams in construction projects.

7. Protective Layers for Infrastructure

• Bridges and Overpasses: It provides a protective layer for bridges and overpasses, helping to guard against environmental wear and tear.

Maintenance of Oxidized  Bitumen

Maintaining oxidized bitumen is crucial for ensuring its longevity, optimal performance, and resistance to environmental factors. This article aims to provide practical and effective maintenance strategies for oxidized bitumen, emphasizing the importance of regular inspections, cleaning, repairs, and protective measures. By following these maintenance practices, users can maximize the lifespan and functionality of oxidized bitumen in various applications.

1. Regular Inspections
2. Cleaning and Debris Removal
3. Handling and Transfer
4. Storage and Containment
5. Emergency Preparedness

Differences between oxidized bitumen and conventional bitumen

Oxidized bitumen and conventional bitumen differ significantly in production, properties, performance, applications, and cost. Conventional bitumen is produced through crude oil distillation, resulting in a softer, more elastic material with a lower softening point, making it ideal for flexible applications like road paving and roofing but less durable against aging and high temperatures.

Oxidized bitumen, created by blowing air through heated bitumen, is more rigid, has a higher softening point, and offers better temperature stability, durability, and resistance to aging, UV, and weathering, making it suitable for roofing membranes, waterproofing, and industrial coatings.

While conventional bitumen is cheaper and easier to produce, it may incur higher long-term maintenance costs, whereas oxidized bitumen, though more expensive initially, provides cost savings over time due to its longevity and reduced maintenance needs.

Oxidized Bitumen Specification:

Among these bitumen, the most widely used oxidized or blown bitumen in the market is R85/25 that whose softening point is 85 and its penetration grade is 25.
Blown Asphalt 85/40 is popular in some European countries like Denmark, Norway, Finland, and Sweden.

The standard test methods used to obtain each property are as below:

• Specific Gravity: ASTM D70
• Penetration : ASTM D5
• Softening Point: ASTM D36
• Loss on heating: ASTM D6Flash point: ASTM D92
• Solubility: ASTM D4
• Ductility: ASTM D113
• Spot test: AASHTO 102

Health & Safety for Oxidized Bitumen

workers should comply with these tips:

• Ventilation: workers anywhere working should have appropriate Ventilation Because Blown Bitumen can release fumes when heated, which can be harmful if inhaled.
• Protective Equipment: workers should use heat-resistant gloves, safety shoes, long-sleeved shirts, long trousers, and safety goggles.
• Fire Safety: Workers work with high temperature for this reason Keep bitumen away from open flames or sparks and have appropriate fire extinguishing equipment on hand.

Oxidized Bitumen Packing:

Oxidized Bitumen has a different Packing and you can see some of these packings:

• Meltable Polyamide Bags in (20&25 Kg)
• Carton Box in (20,25&40 Kg)
• Kraft Bags in (20,25&40 Kg)
• Blocks in (20,25&40 Kg)
• Drums in (20&25 Kg)