Constructed of blends of polymers and elastomers, foam rubbers are some of the most durable, versatile and unique materials in the world of foam. Given their unique characteristics that make them suitable for a long list of applications, neoprene sheets and gymnastic rubber are two of the most popular and recognized foam rubber materials on the market. These utilitarian products are able to be easily customized and manipulated to fit any use where their performance qualities provide the best solution.
Neoprene foam rubber is a middle-weight and resilient material that is created in multiple variations. The three most utilized varieties of this material are chloroprene rubber (CR), styrene-butadiene rubber (SBR) and ethylene-propylene-diene-monomer (EPDM). Each one of these neoprene types contain a variation in its formula, which translates to differences in the final product. But by sharing the same base formulation, these similar materials each have their own set of performance characteristics that make them better for certain applications while maintaining the utility of their foam rubber base.
The oldest of the three, CR is also considered to be the most basic foam rubber variety. This material is durable, but not to the degree of some of the blended forms which have undergone formulaic additions to enhance performance attributes. Despite this, it remains an excellent material for use as seals, bearings and gaskets because of its resistance to many fluids, including water and oils. Developed during World War II to compensate for the shortage and price of natural rubber, SBR is a blending of the monomers styrene and butadiene. Its advantages over natural rubber include better resistance against water, organisms and abrasions and better flex resistance, tear resistance and greater tensile strength.
EPDM rubber is the most popular foam rubber product today. Its formulation of monomers is more affordable compared to other types while providing excellent moisture and temperature resistance, very useful traits for gasket and insulation purposes. It is also very resistant to weather, sunlight, oxidation, chemicals and petroleum derivatives like other similar materials, but it also features Ozone resistance, which is not a characteristic of all foam rubber materials. Very structurally consistent, this closed-cell foam can be cut to very thin sections, even down to 1/32 of an inch. They also can be cut to larger sections multiple inches thick or laminated together for even thicker sections and can be found in regular and high quality varieties as well. EPDM foam rubber sheets have also found a niche use as roof liners and aiding in the collection of rainwater because of its non-toxic formulation. And as previously stated, EPDM uses more affordable materials in its formulation, making it a less expensive product than CR neoprene types.
Another recognizable foam rubber product is resilient gymnastic rubber. This high density foam product is most frequently seen as matting or padding in gymnasium flooring or in use as a fitness mat at health clubs. Gym rubber has a similar base to the neoprene rubber types with its butadiene rubber formula, but also includes nitriles (NBR). One of the most common gym rubber varieties is polyvinyl-chloride nitrile-butadiene-rubber, or PVC/NBR. Beyond their athletic flooring uses, these dense and flexible foam rubbers are often used as kneeling and camping mats outdoors because they provide cushion against rough surfaces while having firmness that allows for stability and resilience against pressure. They are also used in building insulation because their ratio of density to thickness provides excellent performance for the amount of space it takes up. Gym rubber is most often cut in simple sheets but can be easily made to have interlocking edges for padded floor tiles or temporary matting.
Foam rubber materials can be used in a range of applications, stretching from the money-saving and practical, to recreational and relaxing, like sleeping pads while camping. Their formulaic variances mean they all share a base of similar general traits but still have specific uses and applications in which they thrive.
CH James is a product writer and researcher at Foam Factory, Inc. in Clinton Township, Michigan. To view their line of foam rubbers and other closed-cell foam products, visit http://www.foambymail.com/closed-cell-foams.html or http://www.thefoamfactory.com/