O-rings, made of EPDM-compounds from different suppliers were tested in a benchmark regarding their resistance against hot water up to 180 degrees C. Next to these aging tests,TOC-content and electrolytic corrosion were examined. in the theoretical part the way to a sensible choice of test parameters is discussed. Moreover a scoring system was established to rank the different materials in an objective way. The outcome of this benchmark is that the O-Ring material 70 EPDM 291 (Freudenberg) shows superior aging resistance against hot water up to 180 degrees C in comparison with the other tested materials in addition 70 EPDM 291 has a broad spectrum of drinking water approvals, it takes a leading position as a real high performance EPDM material.

O-rings made of EPDM-compounds from different suppliers were tested in a benchmark regarding their resistance against hot water up to 180°C. Next to these aging tests, TOC-content and electrolytic corrosion were examined. In the theoretical part the way to a sensible choice oftest parameters is discussed. Moreover a scoring system was established to rank the different materials in an objective way. The outcome of this benchmark is that the O-Ring material 70 EPDM 291 (Freudenberg) shows superior aging resistance against hot water up to 180°C in comparison with the other tested materials. In addition 70 EPDM 291 has a broad spectrum of drinking water approvals, it takes a leading position as a real high performance EPDM material.

0-rings made of EPDM-compounds from different suppliers were tested in a benchmark regarding hot air resistance up to 150 °C. In the theoretical part the way to a sensible choice of test parameters is discussed. Moreover a scoring system was established to rank the different materials in an objective way. The outcome of this benchmark was that the 0-Ring material 70 EPDM 291 (Freudenberg) showed superior aging resistance against hot air up to 150 °C in comparison with the other tested materials. Additionally the compound has a broad spectrum of drinking water approvals. Therefore it takes a leading position as a real high performance EPDM material.

O-rings made of EPDM-compounds from different suppliers were tested in a benchmark regarding hot air resistance up to 150 degrees C. In the theoretical part the way to a sensible choice of test parameters is discussed. Moreover a scoring system was established to rank the different materials in an objective way. The outcome of this benchmark was that the O-Ring material 70 EPDM 291 (Freudenberg) showed superior aging resistance against hot air up to 150 degrees C in comparison with the other tested materials. Additionally the compound has a broad spectrum of drinking water approvals. Therefore it takes a leading position as a real high performance EPDM material.

The appropriate laboratory test program in dependence on different kind of applications is introduced to qualify a defined coating system regarding friction reduction for elastomeric seals. Special tests are introduced for dynamic application as well as for friction reduction during assembly. In addition to improved friction reduction coated seal still has to guarantee leak tightness. Therefore sealing performance is visualised by typical pattern of defects and monitored by helium leakage test and evaluation of adhesive force of the coated seal.

The appropriate laboratory test program in dependence on different kind of applications is introduced to quality a defined coating system regarding friction reduction for elastomeric seals. Special tests are introduced for dynamic application as well as for friction reduction during assembly. In addition to improved friction reduction coated seal still has to guarantee leak tightness. Therefore sealing performance is visualised by typical pattern of defects and monitored by helium leakage test and evaluation of adhesive force of the coated seal.

Nuclear Magnetic Resonance (NMR) is a well established tool in medical diagnostics and chemical analysis. Magnetic relaxation times correlate with chain mobility in polymer compounds. For example the crosslink density or the state of ageing can be determined. Short measurement times, a very easy sample preparation, and the small amount of sample material needed makes the NMR-method attractive for the rubber industry. The principle of the method is briefly reviewed and the use of NMR in material development, process engineering and quality control of rubber products is discussed. Finally an outlook on the future possibilities of NMR in the rubber industry is given.

Considering permanently increasing demands for seal materials, and because of specifications becoming stricter all the time it is absolutely necessary to deal intensively with the topic permeation of media through elastomeric materials in order to create new innovative sealing concepts. This article is divided into four parts. Within the first two parts the basics of the permeation process are briefly discussed and different measurement techniques for the characterisation of permeation of liquid and gaseous media through elastomeric compounds are presented. The third part of the article deals with material properties of different elastomer compounds and the parameters influencing permeation behaviour. The influence of the temperature, of the type of elastomer, of the concentration of filler within the compound and of the type of gas permeating through the elastomer is discussed. The last part of this article focuses on development trends considering elastomeric seal materials. An approach in order to reduce permeation through elastomeric seal materials is presented.

The interaction between various structured hydrocarbons and nonpolar types of rubber (EPDM, NR, 1,2-BR, cis-BR and SBR) was studied by Inverse Gas-Chromatography (IGC) in a temperature range of process-technological relevance. The information contained in the specific retention volumes led to a quantitative characterization of the systems. The solvent quality of the alkanes improved in each of the rubbers studied as the number of C atoms increased. Because of their high contribution to mixing entropy cyclic hydrocarbons have the best solvent properties. Aromatic structures in EPDM make only a small additional contribution to the mixing free energy. The thermodynamic solvent quality experiences a steady improvement as the delta parameter of the rubbers rises. In the temperature range studied, the higher the number of C atoms, the better the interaction between alkanes and covalent types of rubber.