Glossary

Performance infill for artificial turf systems with a special formulation that can contribute to a considerably lower surface temperature (up to 25%).

The density of an object is defined as its mass per unit volume. The specific density represents the density of a material in relation to the density of water. In the case of filled materials, such as EPDM granules, the density can be calculated by determining the mass and its displacement of water, for example.

Performance infill for artificial turf systems with even more stringent environmental compatibility requirements than those customary in Germany (e.g. Austria and Switzerland "inhibition of nitrification" or "luminous bacteria tests").

Ethylene propylene diene monomer rubber is a terpolymer elastomer. Due to its saturated supporting structure, EPDM is highly resistant to ageing, weathering, UV and ozone.The material is resistant to many acids and alkalis but not to mineral oils. Depending on the composition of the compound, application temperature from -40 °C to +120 °C.

Advantages:

•  excellent resistance to weathering, ageing, ozone, chemicals, hot water, steam and polar solvents such as acetone, methanol and esters
• outstanding electrical insulation properties
• very good heat resistance
• good behaviour at low temperatures

Disadvantages:

• ow resistance to aliphatic and aromatic hydrocarbons (mineral oils, petrol and fuels)

Trade names: NORDEL^®, KELTAN^®, VISTALON^®, DUTRAL^®, BUNA EP^®

By using mineral flame retardants, EPDM granules can be made flame-resistant (formerly "B1" in accordance with DIN 4102-1, now C_fl-S1 according to DIN EN ISO 13501-1).

Organic pigments are based on carbon compounds, while inorganic pigments are not  (e.g. iron oxide for red).

The "Camsizer" is an optical device for analysing the grain sizes of our granules. In addition to the granule size, it also measures their distribution and the respective proportions of different granule sizes. Camsizer analysis has superseded the classical grading curve using vibratory screens.

Hardness is defined as being a material's resistance to penetration by a harder object under a defined force. Thermoplastic materials and elastomers are normally measured by the Shore method using a durometer.  

A distinction is made between 2 types:

Shore A for soft rubber; it is measured using a truncated cone.

Shore D for hard rubber and thermoplastics; it is measured with a rounded conical point.

A material's loose bulk density is equal to the weight of numerous particles of the material per unit volume. The material's bulk density depends on its density, shape and handling. Standards require that the loose bulk density of free-flowing particles be measured according to DIN EN ISO 60.

Peroxide crosslinking is a radical reaction. As a result, even completely saturated (diene-free polymers) can be crosslinked using this model. This is consequently an alternative means of creating equally elastic links, as with sulphur crosslinking.

SBR stands for styrene butadiene rubber, a low-cost product which, due to its structure, displays little resistance to weathering and therefore requires extensive protection against ageing. SBR requires reinforcing fillers in order to obtain good properties. The material is primarily used for tyres.

This name is generally used for artificial turf infill granules made from granulated tyres. The materials have a high polymer content, having been developed for tyres. Due to the fact that recycled materials are used, the granules are very good value for money.

Rubbers must be crosslinked in order to make them elastic (elastomers). Rubber materials containing dienes are most commonly crosslinked with sulphur. To this end, the rubber is mixed with sulphur and accelerators in a compounding process. In a second step, this mixture is then vulcanized under pressure and at high temperatures to yield a large-mesh, elastic network.

These mechanical values are indicators of a material's durability and load-bearing capacity. Tensile strength is defined as the force per unit area (MPa = N/mm²) that is needed to pull a material apart; in the case of EPDM granules, it correlates with the crosslinking density, the tensile strength increasing with the crosslinking density.  
Studies have shown that the granules' values have a direct effect on the properties of the system. 
Elongation is expressed in % of the initial length (30% means that the specimen has "grown" to 130%).