Organosilicon refers to polyorganosiloxanes (also known as polysiloxanes), silicon oxide compounds, silicone oils, and silicone resins. It is a type of mold release agent with good isolation properties, causing little contamination to the mold, and is mainly used for model products made of natural rubber, plastics, and butyl rubber. 
Introduction
Rubber and plastic products are processed and formed in molds. The rubber and plastic materials come into contact with the surface of the molds. Due to the micro-defects such as the unevenness of the working surfaces of the molds, when the rubber and plastic products are separated from the molds, there will be certain frictional resistance. During the injection or extrusion processing of rubber and plastic, negative pressure often forms between the rubber and plastic materials and the molds, or adhesion occurs due to physical adsorption or chemical bonding between them, making it difficult for the rubber and plastic products to be separated from the molds after formation. 
To reduce the adhesion or bonding between the product and the mold, additives that can form an effective isolation film are often used - these are called release agents. A release agent is an interface film applied to the surfaces of two objects that are prone to stick to each other, creating an isolation layer between the bonded and the bonded objects, making it easier to peel off and facilitating the removal of the product. 
There are many basic substances that can be used as mold release agents. Common mold release agents include inorganic substances, organic substances and polymers. Common inorganic mold release agents include graphite powder, talc powder, mica powder, potassium dichromate, etc. Common organic mold release agents include fatty acids, fatty acid soaps, various waxes, ethylene glycol, etc. These mold release agents also have the function of lubricants. Polymer-based mold release agents mainly include polyvinyl alcohol, cellulose acetate, organic fluoropolymer and organic silicone polymer, among which organic silicone polymer is the most suitable mold release agent. 
Organic silicone release agent is prepared from organic silicon oxides. Its advantages include good heat resistance, moderate surface tension, easy formation of a uniform isolation film, long release life, non-toxicity, good gloss, and no adhesion to the resin. It is widely used in various fields such as plastics and rubber. However, the disadvantage is that after release, the surface of the product has an oily layer, which requires secondary processing and surface cleaning. Commonly used ones include silicone oil, silicone rubber, emulsified silicone oil, and silicone grease, etc. 
Organic silicone release agents are currently the mainstream products in the mid-range market of rubber and plastic release agents. They are widely used in the processing of resins such as polyurethane, rubber, polyethylene, and polyvinyl chloride. Overseas, the main organic silicone release agents for sale are those from Dow Corning, Japan's Oriental Oil and Chemical Industry Co., Ltd., and Shin-Etsu. There are many factories in China that produce organic silicone release agents, but their scales are relatively small. 
Types of organic silicone release agents Classification of organic silicone release agents 
Classified by product composition and form 
(1) Organic silanes and their solutions: 
The base material of the release agent is organic chlorosilane or organic alkoxysilane. Directly using organic silanes as a release agent has certain limitations. Among them, organic chlorosilane undergoes dehydration and hydration in the film-forming process by absorbing moisture from the air, and the released hydrogen chloride is corrosive. Therefore, it is only suitable for molds that are resistant to corrosion, such as glass, ceramic solutions, and porcelain. 
(2) Silicone oil and its solutions, ointments: 
The base materials of the demolding agent are inert linear organic silicon polymers such as methyl silicone oil, methyl phenyl silicone oil, and various modified silicone oils. The commonly used silicone oil-based demolding agents are solutions of silicone oil as the main component, with organic solvents like toluene and gasoline added for preparation. 
By adding silica oil along with white carbon black, silica soil, mica powder and other solid components, and then mixing them, a semi-solid paste-like release agent can be produced. 
(3) Silicone rubber and its solutions: 
Liquid silicone rubber can be directly used as a release agent. However, the more common application is to mix the silicone rubber with organic solvents to form a silicone rubber solution, and then combine it with crosslinking agents, catalysts and other auxiliary components to apply it onto the mold surface to form a desorbing silicone rubber working film. 
(4) Silicone resins and their solutions: 
The base material of the release agent is methyl silicone resin, methyl phenyl silicone resin, etc., which can be cross-linked and solidified through polymerization. Usually, the above-mentioned silicone resins are dissolved in organic solvents such as ethanol, toluene, and gasoline to prepare a silicone resin solution. The release agent is then applied to the surface of the mold by spraying or dipping methods, and the silicone resin is cured into a working film through heating or other means. 
(5) Silicone emulsion: 
The main component is silicone oil or silicone resin, and emulsifiers, water, etc. are added to prepare an emulsion. The water-based emulsion coated on the mold surface will form a release agent working film after the moisture evaporates. 
(6) Silicone aerosol: 
The main component is silicone oil, combined with refrigerants such as Freon and butane, and mixed and encapsulated in a sealed container. When applied as a coating on the release agent, the release agent carries the main component of the release agent and sprays it onto the mold surface. The release agent quickly evaporates, and the residue forms the working film of the release agent. 
(7) Other types: 
In addition, some use silicone rubber to directly manufacture elastic molds. The silicone rubber molds not only have good heat resistance, but also possess excellent properties of anti-adhesion and easy demolding, making them particularly suitable for the molding and demolding of complex-shaped products. 
Classified by service life 
(1) Temporary release agent: 
During the working process of this demolding agent, some components gradually deplete, meaning that the demolding agent is transferred to the product. Temporary demolding agents are used only once after application or for a limited number of uses. Organic silicon demolding agents based on various inert silicone oils are typical examples of temporary demolding agents. 
(2) Semi-permanent release agent: 
The film layer formed after the curing of the release agent firmly adheres to the surface of the mold. During the processing and shaping of the product and after the product is demolded, the release agent does not transfer to the product and basically does not dissolve, thus becoming a semi-permanent type of release agent. 
Classified by the application object or the usage process conditions 
According to the application target, for example: polyurethane demolding agent, tire demolding agent. 
Name them according to the actual application process, for example: high-temperature resistant release agent, acid and alkali resistant release agent, etc. 
Characteristics of organic silicon release agents Comparison of various organic silicon release agents 
The application methods of the solid silicone oil type and aerosol type release agents are the most convenient. All you need to do is simply spray the release agent onto the mold surface, and then you can proceed with the processing operation. The products can be released easily. 
The application of paste-type demolding agents is slightly more complicated than the former method. However, after the working film layer is formed, it is suitable for molds with rough surfaces, and it can be used for more effective demolding times. 
Compared with solution-based organic silicone release agents, water emulsion-based ones do not use organic solvents and thus do not cause environmental pollution. However, the peeling force of water emulsion-based release agents is relatively greater, and their continuous use times for release are also fewer compared to solution-based ones. 
Comparison of Organic Silicon Release Agents and Non-Silicon Type Release Agents 
Comparison of the form and type of release agents: Usually, paraffin, fatty acids, etc. are used as release agents, and there are only simple forms. Correspondingly, organic silicon release agents have various forms and types, thus providing convenience for selection to meet different usage requirements. 
Comparison of working temperatures of release agents: Due to the fact that the high molecular framework of the organic silicon polymer is composed of silicon-oxygen bonds, it has excellent heat resistance and its stable temperature exceeds that of almost all types of rubber. Therefore, there will be no problems such as thermal decomposition or carbonization of the release agent. 
Comparison of demolding peel strength: Silicone is a material with low surface energy, so its molded products have the lowest demolding peel strength. That is to say, products using silicone release agents are the easiest to demold. 
Comparison of mold release agent safety: In terms of the surface energy of the materials, both organic fluoropolymer and organic silicone polymer belong to the lowest surface energy materials artificially synthesized. However, when the temperature exceeds the allowable range, the organic fluoropolymer may release toxic substances; while the organic silicone material has good heat resistance, even if the by-products from overheating decomposition are used, they are safe and non-toxic. 
Life span of release agent: Due to the excellent heat resistance of organic silicon release agents, they can withstand the processing temperatures of various plastic products. Especially the non-migratory organic silicon release agents based on silicone resin have not only a high working temperature but also stable components that do not migrate, demonstrating an extremely long life span of the release agent. 
Organic silicon release agents are widely used in the processing of various rubber and plastic materials. They can be applied in both extrusion and injection molding processes, as well as in the forming of molded products. They can reduce labor intensity, enhance production efficiency, and improve the quality of processed products.