Abstract: The hydrosilylation of polymethyl-hydrosiloxane (PMHS) with alkenes comprising alkyl, epoxy alkyl, and other functional groups under the action of platinum catalysts were investigated in this work. As reported herein, the synthetic routes, reaction conditions, synthetic procedures were studied. Moreover, a more effective preparation method was conceptualized, leading to the formation of modified silicone oil containing alkyl, epoxy alkyl, and other functional groups capped. In addition, we explored the reaction kinetics and thermodynamic processes through online monitoring technology in an attempt to establish the relationship between the monomer structure and the functionalization degree of organosilicon. The chemical reaction rate and the reaction conversion rate were determined using real-time in-situ FT-IR spectroscopy. Nuclear magnetic resonance (NMR) spectroscopy and gel permeation chromatography (GPC) were used to characterize the functionalized polymers. The results indicated the steric structure and electronic effects of the substituents directly attached to the double bond, which play an important role in the creation of the desired products and the reaction’s total conversion time. Furthermore, the steric hindrance leads to the greatest impact on reaction activity and conversion, followed by electronic effects like conjugation and induction. It is worth noting that partially modified polymers with pendant alkoxy groups have promising applications in resin modification, coating, soft finishing, and decontamination.Graphical abstract: