Poly-Butadiene Rubber

Manufacturing Process

1. Polymerization Methods:
   • Emulsion Polymerization: Involves the polymerization of butadiene in an aqueous emulsion.
   • Solution Polymerization: Uses a hydrocarbon solvent and specific catalysts to polymerize butadiene.
2. Emulsion Polymerization Process:
   • Preparation: Butadiene is mixed with water, surfactants (to stabilize the emulsion), and polymerization initiators (such as potassium persulfate).
   • Reaction: The mixture is polymerized under controlled temperature and pressure conditions, typically in a batch or continuous reactor. The initiators start the reaction, resulting in the formation of butadiene polymers in an aqueous dispersion.
   • Coagulation: The resulting latex (an emulsion of polymer in water) is coagulated using acids or salts to form a solid rubber.
   • Drying: The coagulated rubber is then washed, filtered, and dried to obtain dry polybutadiene rubber.

Characteristics

• Elasticity: High elasticity and resilience, which makes PBR particularly useful where flexibility is important.
• Wear Resistance: Excellent abrasion resistance, making it ideal for high-wear applications like tires.
• Low Temperature Flexibility: Retains flexibility at low temperatures, beneficial for cold weather applications.
• Low Rolling Resistance: Helps in improving vehicle fuel efficiency by reducing rolling resistance.
• Moderate Chemical Resistance: Offers good resistance to chemicals, oils, and solvents, though not as high as some other synthetic rubbers.

Key Characteristics

• Tensile Strength: Provides good tensile strength, although it is generally lower than some other types of synthetic rubber.
• Hardness: Typically has a lower hardness, which can be adjusted by compounding.
• Durability: Demonstrates good durability with resistance to cracking and wear.

Types

1. High Cis-1,4 Polybutadiene: Features a high cis content (over 90%), providing superior impact resistance and elasticity.
2. Low Cis-1,4 Polybutadiene: Has lower cis content and is often used where different processing characteristics or lower elasticity are required.

Applications

• Tires: Extensively used in tire manufacturing due to its high wear resistance and low rolling resistance, enhancing tire performance and fuel efficiency.
• Automotive Parts: Utilized in various automotive components such as gaskets, seals, and vibration isolators.
• Industrial Goods: Found in products like conveyor belts, hoses, and industrial seals due to its durability and flexibility.
• Footwear: Used in the production of soles and other footwear components for its wear resistance and flexibility.
• Coatings and Adhesives: Applied in coatings and adhesives for its flexibility and adhesion properties.

Polybutadiene Rubber’s distinct properties, such as its elasticity, wear resistance, and performance at different temperatures, make it an essential material in many applications, particularly where durability and flexibility are key.