The properties of rubbers are subject to change as a result of ageing, ultimately to the point where the material is no longer capable of fulfilling its function. After a brief introduction to the main environmental and mechanical factors affecting performance, this review focuses on the thermo-oxidative ageing of rubber. It considers the methods of, and the published results from, both natural and accelerated tests. A major section of the report is devoted to exposure and test techniques with discussion of the methods of physical and chemical analysis. An additional indexed section containing several hundred abstracts from the Rapra Polymer Library database gives useful references for further reading.

The properties of rubbers are subject to change as a result of ageing, ultimately to the point where the material is no longer capable of fulfilling its function. In many applications, the longevity of rubber components is of critical importance. During its lifetime a rubber may be subjected to a variety of exposure conditions leading to different types of degradation. After a brief introduction to the main environmental and mechanical factors affecting performance, the authors of this Rapra Review Report focus on the thermo-oxidative ageing of rubber. As the lifetime for some products is meas.

Annotation This report details the results of accelerated heat ageing studies undertaken on re-mixed samples of those materials studied for the natural ageing study and on the 20 new compounds chosen to represent polymers not available in 1958 and to reflect changes in compounding practice. In addition to those properties studied for the artificial weathering exposures compression set and dynamic properties were also measured.

The object of this publication is to provide practical guidance on assessing the useful service life of rubbers. It describes test procedures and extrapolation techniques together with the inherent limitations and problems. This Guide seeks to be comprehensive but concentrates on the most common environmental effects causing degradation and the most important mechanical properties of rubbers. The test procedures used are outlined and the relevant d104books and International standards are referenced.

This report is an output from the Weathering of Elastomers and Sealants project, which forms part of the UK government's Department of Trade and Industry's Degradation of Materials in Aggressive Environments Programme. A long-term natural ageing programme was started in 1958 when 19 rubber compounds were exposed at 3 locations. The final sets of test pieces were withdrawn in 1998 giving a total of 40 years of natural ageing. The results of the physical tests carried out at intervals over the period were published in 2000 by Rapra in 'Natural Ageing of Rubber?Changes in Physical Properties over.

Natural rubber, Synthetic rubber, Vulcanized rubber, Plastics and rubber technology, Thermoplastic polymers, Thermal testing, High-temperature testing, Heat ageing tests, Ageing tests, Accelerated testing, Test equipment, Test specimens, Testing conditions, Reproducibility, Reports