STANDARD MATERIALS
NEOPRENE RUBBER is a great elastomer with medium resistance to sunlight oxidation and some petroleum products. Added advantages include medium resistance to water and selected chemicals. Neoprene rubber can be used as rubber mats, rubber gaskets, and rubber strips.
GUM RUBBER exhibits high resilience, good tensile strength, and tear resistance. In addition to notable wear resistance, natural gum rubber also offers low permanent set characteristics plus good flexing qualities at low temperatures. Gum rubber is a tough material with excellent tear resistance. Also known as floating sheet stock, this material is non-marking and non-toxic.
NITRILE RUBBER / BUNA-N is highly resistant to petroleum oils, aromatic hydrocarbons, and many acids. Nitrile has superior elongation properties, great resilience tensile, and compression set properties. Used for O-rings, gaskets, sealants, grommets, and tubing pads. Nitrile rubber / Buna-N Rubber provides excellent oil resistance and good protection from impact abrasion and oxidation.
EPDM RUBBER is the best rubber for outdoor applications. EPDM can be used as pond liners, roof liners, and applications where resistance to harsh weather is required. EPDM rubber also has excellent color stability, heat resistance, and dielectric qualities. Moderate resistance to acids. EPDM rubber provides excellent protection from ozone and sunlight degradation. Often used in applications where long-term weather resistance is essential.
SILICONE RUBBER is best suited for many medical, electronic and aircraft rubber requirements where temperature extremes are involved. Good resistant to weather aging and many chemicals. Low permeability to gas, air, and high dielectric strengths. Silicone rubber offers excellent resistance to ozone and temperature extremes. Silicone rubber has a high biochemical purity. Silicone rubber is perfect for health care and pharmaceutical applications.
SBR RUBBER (Styrene-butadiene rubber) is a synthetic copolymer used extensively due to its relatively low manufacturing cost. Certain types of SBR offer improved wear resistance, while others provide better low temperature flexibility. SBR has similar resistance to solvents and chemicals as natural gum rubber, and it can be successfully bonded to a wide range of materials. When exposed to petroleum derivatives, the performance of this rubber is inferior to many other synthetics, and in some applications, the product's heat aging characteristics are slightly deficient.
SPONGE RUBBER is a closed cell expanded rubber. The raw compound is mixed with a chemical blowing agent. All of the materials listed above can be produced in a closed cell sponge configuration. Constant deflection of closed cell sponge rubber may cause the gas to permeate through the cell walls. Over compression of the closed cell sponge such as beyond 50% deflection, may cause the cells to burst. When a closed cell sponge gasket has been over compressed, the gasket may rebound very slowly, or not at all, compromising the integrity of the gasket. Most closed cell sponge gaskets should be deflected 20 to 35% for optimal sealing performance. These properties are discussed in ASTM D1056, ASTM D6576 and Mil-R-6130C.
SPECIALITY MATERIALS
SANTOPRENE® RUBBER is a thermoplastic rubber with performance characteristics similar to vulcanized rubber, such as flexibility and low compression set, with the processing ease of a thermoplastic. Santoprene® rubber fits into the middle of the cost and performance spectrum of both thermoplastic and thermoset rubbers. It offers the dual advantages of low-cost thermoplastic processing and vulcanized rubber performance. Santoprene® rubber consists of highly cross linked rubber particles dispersed throughout a continuous matrix of thermoplastic material. It can be injection molded, extruded, blow molded and thermoformed. Santoprene® rubber has the environmental resistance equivalent to general purpose EPDM rubber compounds, while fluid resistance is comparable to general purpose polychloroprene rubber compounds.
VITON® RUBBER is a fluoroelastomer which is well known for its excellent temperature resistance (400°F/200°C). It offers excellent resistance to aggressive fuels and chemicals. Viton® is available in several grades that are application specific. The latest grade of Viton® utilizing Advanced Polymer Architecture (APA) is indicated by a 'S' designation. The grade selection is based up the end-use application and whether the finished part must provide resistance to amines; caustics; hydrocarbon fluids; and flexibility at low temperature.
HYPALON® RUBBERis a chlorosulfonated polyethylene and has demonstrated long life in harsh environments. It has outstanding resistance to most chemicals, heat and oil. Additionally, Hypalon® is flame resistant; has excellent color stability, weather and abrasion resistance; low moisture absorption; and good dielectric qualities. Like most synthetics, Hypalon® is superior to natural rubber in temperature, oil and ozone resistance. However, it is generally affected by concentrated oxidizing acids, esters, ketones, chlorinated, aromatic and nitro hydrocarbons.
