I. Classification by Chemical Structure: Four Core Polymer Systems
Silicone Oil: Mainly composed of linear polysiloxanes, it is a liquid oil at room temperature. Based on different organic groups, it can be divided into methyl silicone oil, phenyl silicone oil, amino silicone oil, etc., with methyl silicone oil being the most widely used. Silicone oil can be modified to produce special products such as damping silicone oil and diffusion pump silicone oil, which are widely used in textile printing and dyeing auxiliaries, high-grade lubricants, and insulating oils.

Silicone Rubber: A high-molecular-weight polysiloxane with a three-dimensional cross-linked structure, divided into room temperature vulcanizing silicone rubber (RTV) and high temperature vulcanizing silicone rubber (HTV). RTV is based on 107 rubber and used for building sealing; HTV is compounded and processed to make remote control housings, automotive ignition cables, etc.; liquid silicone rubber (LSR) is formed by reacting vinyl silicone oil with a cross-linking agent and is currently a key development direction.

Silicone Resin: Highly cross-linked thermosetting polysiloxanes, represented by MQ silicone resin, possessing excellent heat resistance and electrical insulation properties. Primarily used as insulating varnish for H-class motors, impregnating material for electrical windings, and for products such as bushings made after impregnation with glass cloth.

Silane Coupling Agents: Functional compounds that connect organic and inorganic interfaces through silicon-oxygen-metal bonds. They are divided into two main categories: silicon-functionalized silanes and carbon-functionalized silanes. Widely used as adhesion promoters in paints and plastic/rubber processing, they can significantly improve the performance of composite materials.

II. Classification by Product Form: Three Major End-Use Application Forms
The downstream products of polysiloxanes exhibit a proportion pattern of "66.9%-29.5%-3.6%": silicone rubber accounts for 66.9%, constituting the core application; silicone oil accounts for 29.5%, forming an important supplement; and silicone resin accounts for 3.6%, meeting special needs. This structure reflects the complete form coverage of organosilicon materials from elastomers to fluids, supporting their diversified applications in sealing, lubrication, and insulation.