The properties and preparation process of chemical silicone oil
introduction
Silicone oil, also known as silicone oil, is a type of polysiloxane formed by the alternating arrangement of silicon and oxygen elements. Usually in the form of liquid or gel, it is widely used in various industrial fields due to its excellent chemical stability and high temperature resistance. This article will provide a detailed introduction to the properties, preparation methods, and application fields of silicone oil.

Properties of silicone oil
The main component of silicone oil is polysiloxane, which has longer Si-O bond lengths and larger bond angles in its molecular structure, giving the molecular chain excellent flexibility. In addition, the shielding effect of organic groups on the molecular side chains weakens the interaction between the main chains of the molecules, endowing silicone oil with low surface tension. These unique structural characteristics give silicone oil a variety of excellent physical and chemical properties:


Stability: Silicone oil has high chemical stability and is not easily oxidized or degraded.
Heat resistance: Can be used for a long time within the temperature range of -50 ℃ to+180 ℃.
Electrical insulation: high breakdown voltage resistance, arc resistance, corona resistance, low dielectric power consumption.
Hydrophobicity: Not easy to absorb water, with good hydrophobicity.
Physiological inertia: non-toxic to the human body, suitable for medical and cosmetic fields.
The density of silicone oil is about 0.93 g/cm ³, and it appears as a colorless and transparent liquid with low vapor pressure, high flash point and ignition point, and low solidification point. As the molecular weight increases, the viscosity of silicone oil also increases, ranging from 0.65 to millions of centixtles.


Preparation method of silicone oil
The preparation of silicone oil is mainly achieved through the synthesis and polymerization reaction of organosilicon monomers. The commonly used methods include direct method, indirect method, and cyclic silicone oil synthesis method.


Direct method: Silane and oxygen are directly reacted at high temperature to produce silicic acid and water, which are then subjected to dehydration, decarbonization, and other steps to ultimately obtain silicone oil. The silicone oil prepared by this method has high purity but high cost, making it suitable for high-end fields.
Indirect method: Partially oxidize silane to form siloxane under the action of an oxidant, and then decompose siloxane into silicone oil through heating, pressure, and other treatments. The silicone oil prepared by this method has a lower cost but lower purity, making it suitable for some low-end fields.
Synthesis method of cyclic silicone oil: Silane is cyclized under the action of a catalyst to produce cyclic silicone oil, which is then prepared through steps such as cracking and hydrogenation. The molecular structure of silicone oil prepared by this method is relatively stable, with good thermal stability and mechanical properties, and is suitable for high heat resistance fields.
Types of silicone oil
There are many types of silicone oil, which can be divided into methyl silicone oil, amino modified silicone oil, epoxy modified silicone oil, polyether modified silicone oil, etc. according to the different organic groups. Among them, methyl silicone oil is the most commonly used type of silicone oil, with all its organic groups being methyl. Through chemical modification, silicone oil with specific properties and application characteristics can be obtained.