The dynamic mechanical properties of hybrids of chlorinated polyethylene (CPE) and 3,9-bis[1,1-dimethyl-2[beta-(3-tert-butyl-4-hydxoxy-5-methylphenyl)propionyloxy}ethyl] -2,4,8,10-tetraoxaspiro[5,5]-undecane (AO-80) were investigated. The CPE/AO-80 hybrids showed a novel relaxation in addition to the glass transition of CPE. The novel relaxation is attributed to the dissociation of intermolecular hydrogen bonds within the AO-80-rich domain. The Payne effect, that is, the decrease of the storage modulus E ' with increasing strain amplitude and the appearance of a loss modulus E " maximum at a strain of 0.6%, was observed for the CPE/AO-80 hybrids. This result demonstrates that the AO-80-rich domains within matrix polymer CPE form a network. The Payne effect is considered to be attributed to the mechanical disruption of segment-segment contacts at a sufficiently great strain.