The defect fraction (in Figure ) obtained by exponential decay fit to the IΣMQ during normalization is analogous to the third fraction obtained through T2 analyses in 4.3.2. The amount of defect fraction in NR, corresponding to a T2 relaxation time of about 15 ms, changed from about 3 % for the unaged sample to 9 % for the most weathered sample. In the case of SBR, as expected, no presence of defects was detected. This confirms the complete cross-linking in SBR due to weathering. For the blend, surprisingly, the amount of defect fraction varied from about 2.5 % to only 5 %. Assuming that the defect amount of the SBR phase remains negligible also in the blend, the lower amount of overall defects in the blend is an unexpected finding and probably suggests that NR is also protected from weathering when it is a part of the blend.