End-epoxide silicone oil, the scientific name end-epoxide polydimethylsiloxane, the common synthesis methods are: silane hydrogen addition method, condensation reaction method and end-sealing method.

Hydrosilane addition method: Under the action of a platinum-based catalyst (such as chloroplatinic acid), the Si-H bond in the hydrogen-containing silicone oil reacts with the carbon-carbon double bond in the unsaturated epoxide compound, thereby introducing the epoxy group to both ends of the silicone oil molecular chain. This reaction is based on the electrophilic addition mechanism between hydrogen silane and carbon-carbon double bonds, and the platinum catalyst can reduce the activation energy of the reaction and promote the reaction.

Condensation reaction method: The use of hydroxyl or alkoxy containing siloxane and silane coupling agent containing epoxy groups condensation reaction, by removing small molecules (such as water or alcohol), the epoxy group is connected to the two ends of the silicone oil molecular chain. The essence of the reaction is the formation process of silico-oxygen bond. Under certain conditions, the nucleophilic substitution reaction occurs between silanol or silanoxy groups to generate silico-oxygen bond.

End sealing method: silicone oil containing active end groups is synthesized first, and then an end sealing agent containing epoxy groups is used to react with these active end groups, and the epoxy group is introduced to both ends of the silicone oil molecular chain. The key of this method lies in the reactivity and selectivity between the active end-group and the end-blocking agent.