Elastomers based on peroxide cured rubbers have a wide range of applications,especially because of their chemical resistance and excellent compression set.Observed malfunctions are often the consequence of thermo-oxidative ageing processes,which are chemically caused by competing radical reaction mechanisms at the polymer chain.Softening of the material through degradation or embrittlement through post crosslinking are macroscopic results.Beside of initiating the radical reactions by light and/or temperature in the presence of oxygen,influencing material parameters are(i)polymer structure,(ii)processing,(iii)state of cure and residual content of peroxide,(iv)peroxide type and used coagents.The aging behavior of EP(D)M-model-compounds were investigated using several like methods rheometry,chemiluminescence(CL),low field NMR,FT-IR-spectroscopy,physical testing,quantitative determination of residual peroxide content using HPLC and DSC.The crosslinking time of t9s shows an improvement in resistance and from tioo on up,a significant rise in OIT values is achieved.Using reaction kinetic data from from crosslinking reactions and residual peroxide concentrations an estimation and prediction of OIT-values in dependency on vulcanization time were successful.The results can be used for an improved compounding of EP(D)M-elastomers.Furthermore the efficiency,reaction mechanism and fate of selected antioxidants in a squalene model system were characterized by CL,GC-MS and LC-MS.TMQ can compensate the detrimental effect of residual peroxide completely.Concerning OIT-values,overall the following priority of antioxidant efficiency including two biobased types could be observed: TMQ > DPPD > Irg 1010 > Irg 1035 > Irg 1076α-tocopherol,> chromanol
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