Properties and Applications of Buna N and Neoprene

Synthetic Rubber Properties

• Buna N stiffens at -45°F, has good abrasion resistance, and good "breakaway" properties when used in contact with metal.
• It is adversely affected by ozone and sunlight, but its properties are improved by the addition of carbon black.

Buna N Applications

• Buna N is used for oil and gasoline hose, tank linings, hydraulic accumulator bags, gaskets, and seals.

Neoprene Properties

• Neoprene is a polymer of chloroprene, has good resistance to oil, and excellent resistance to heat, air, light, and flame.
• It has better light resistance than any other rubber.
• It can be vulcanized without sulfur but cannot be cured to as hard a condition as hard rubber.

Neoprene Applications

• Neoprene is used for oil-resistant hose, carburetor diaphragms, gaskets, shoe soles, barrage balloons, truck tires, cements, tape, and caulking.

Butyl Properties

• Butyl is a copolymer of isobutylene and small amounts of unsaturated hydrocarbons, has excellent gas impermeability, and can be vulcanized with sulfur.
• It cannot be hardened to the condition of hard rubber.

Butyl Applications

• Butyl is used for gas masks, plywood molding bags, life jackets, and chemical storage, and may become the first-choice material for tire tubes.

Thiokol Properties

• Thiokol is a polysulfide polymer, has the highest resistance to deterioration, and is particularly noted for its resistance to aromatic hydrocarbons and aromatic blended gasolines.
• It can be vulcanized with zinc oxide but not to a hardness comparable with hard rubber.

Thiokol Applications

• Thiokol is used for oil hose, tank linings for aromatic aviation gasolines, paint spray hose, gaskets, and seals.

Buna S Properties

• Buna S is a copolymer of butadiene and styrene, can be vulcanized with sulfur and cured to a hardness equal to hard rubber.
• It must be compounded with a black pigment such as carbon black to bring out its best physical properties.

Buna S Applications

• Buna S is the synthetic rubber normally used for tires and tubes as a substitute for natural rubber, and can be used to replace rubber in most applications.

Aircraft Plastics

• Plastics are a large group of synthetic and natural organic materials which can be molded under heat and pressure, cast, extruded, or fabricated into a variety of shapes.
• Plastics have been used in many aircraft applications, such as knobs, handles, paneling, and similar items.