AbstractThe hydrosilylation reaction is very important in silicone‐introducing reactions and in the crosslinking of silicone rubbers. In this study, through Fourier transform infrared spectroscopy, the hydrosilylation reaction between hydrogen‐containing polysiloxane (H‐PDMS) and several kinds of rubber, including styrene–butadiene rubber (SBR), nitrile–butadiene rubber (NBR), chloroprene rubber (CR), and natural rubber (NR), with heat processing was researched. The IR spectra of each compound film were determined after reaction with H‐PDMS under 110°C for different times. Through the quantitative estimation of the progress of the hydrosilylation reaction in the course of the heat processing, we established a method for calculating the changes of the peak areas of the SiH bond and vinyl groups of each sample at each reaction time and computed the ratio of the integral area of SiH and CC to that of each compound. The SiH content decreased 85 and 30% in SBR–Si and NBR–Si, respectively. However, the ratio of the integral area of transmittance of SiH in NR–Si and CR–Si changed very little during the whole process. The SiH content decreased less than 20% in NR–Si and CR–Si. All ratios of the integral area of transmittance of the vinyl groups (RVinyl) of each compound decreased as the reaction time increased at 110°C; the decrease values were very small. The rates of all RVinyl decreases were slow, and the decreasing sequence was the same as the order of decreasing SiH content. The hydrosilylation reaction between H‐PDMS and SBR was quite smooth in the heat processing and better than that between H‐PDMS and NBR. The hydrosilylation reactions of H‐PDMS with NR and CR were less satisfying. The results show that polyolefin rubbers can be modified or crosslinked by H‐PDMS via heat processing. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012