It is a promising method to obtain desirable damping materials by introducing dangling chains used as additional relaxation components. Regrettably, the strict condition of introducing dangling chains limits its application to saturated polymer or low unsaturated degree polymer, for example butyl rubber (IIR). Hence, we propose a simple yet effective method to obtain desirable IIR based damping composites by blending with miscible polyisobutylene (PIB) oligomers as additional relaxation components in this study. As expected, the damping property of IIR is easily controlled by tuning the chain length of PIB oligomers. The effects of PIB oligomers with different chain length on the molecular motions and damping mechanism of IIR were characterized by dynamical mechanical analysis and 2D correlation dynamic mechanical spectroscopy (2DC-DMS). The damping improvement of IIR was ascribed to the additional relaxation generated by introducing PIB oligomers and the movement of sub-Rouse modes and Rouse modes. It seems a universal method to enhance damping property by using miscible polymer oligomers as additional relaxation component. Furthermore, this method may give some inspirations for preparing polymer matrix specially used for damping composites. (C) 2018 Elsevier Ltd. All rights reserved.