Within the silicone family, methyl MQ silicone and vinyl VMQ silicone both occupy an important position, but they have significant differences in structure, properties and applications.


1. Structural characteristics
Methyl MQ Silicone
Methyl MQ silicone is composed of monofunctional R₃SiO₁/₂ (M units) and tetrafunctional SiO₄/₂ (Q units). Among them, R is usually methyl (-CH₃). This structure gives methyl MQ silicone a relatively regular molecular architecture. Its M/Q ratio determines the performance of the resin to a certain extent. Generally, the higher the M/Q ratio, the better the flexibility of the silicone resin.


vinyl VMQ silicone
Vinyl VMQ silicone resin is based on methyl MQ silicone resin, with a vinyl group (-CH = CH₂) introduced into the molecular chain. The introduction of vinyl changes the chemical activity and physical properties of silicone resin. While maintaining the silicon-oxygen main chain structure, the vinyl group becomes an important active point, paving the way for subsequent chemical reactions and performance.


2. Performance differences
chemical activity
Methyl MQ silicone: Because its molecular structure is mainly dominated by methyl and silicon-oxygen bonds, its chemical activity is relatively low. It is relatively stable at room temperature and does not easily react chemically with other substances. This makes it excellent in some applications that require high chemical stability.


Vinyl VMQ Silicone: The presence of vinyl makes it highly chemically reactive. Vinyl can participate in various chemical reactions such as addition reactions and polymerization reactions. For example, during the rubber vulcanization process, vinyl can react with vulcanizing agents, thereby increasing the cross-linking density of silicone rubber and improving its mechanical properties.


heat resistance
Methyl MQ silicone resin: It has good heat resistance and can maintain structural stability at higher temperatures. This is because the silicon-oxygen bond has a higher bond energy and is less likely to break at high temperatures. In some high-temperature environments, such as the packaging of electronic components, methyl MQ silicone can play a very good protective role.


Vinyl VMQ Silicone: It also has excellent heat resistance. To a certain extent, the introduction of vinyl will not significantly reduce the heat resistance of silicone resin. Moreover, in some high-temperature applications, vinyl-based VMQ silicone resin may have better dimensional stability at high temperatures because the cross-linking reaction involving vinyl can form a more stable network structure.


Mechanical properties
Methyl MQ Silicone: Has some flexibility, depending on its M/Q ratio. The high M/Q ratio allows methyl MQ silicone to deform to a certain extent without breaking when subjected to external forces. But overall, its mechanical strength is relatively moderate.


Vinyl VMQ silicone: Vinyl is generally more mechanically strong than methyl MQ silicone due to its ability to participate in cross-linking reactions, forming a tighter three-dimensional network structure. It can withstand greater external forces and is more widely used in products requiring higher mechanical properties, such as seals that need to withstand greater pressure or friction.


Processing performance
Methyl MQ silicone: During processing, due to its low chemical activity, processing conditions are relatively loose. It can perform mixing, molding and other operations under mild conditions. For example, when used as an additive in paint, methyl MQ silicone can be easily mixed evenly with other paint ingredients.


Vinyl VMQ silicone: Due to its high chemical reactivity, processing requires more tightly controlled conditions. For example, in rubber processing, parameters such as temperature and vulcanization time need to be precisely controlled to ensure that vinyl can fully participate in the reaction while avoiding excessive reaction that leads to product performance degradation.


3. Application fields
Methyl MQ Silicone
Coating industry: often used in the preparation of high temperature resistant coatings, weather resistant coatings, etc. In coatings, methyl MQ silicone can improve the hardness, abrasion resistance and chemical resistance of the coating, allowing the coating to maintain good appearance and performance in harsh environments.
Electronic packaging: Due to its chemical stability and heat resistance, it can be used as packaging material for electronic components to protect electronic components from the impact of the external environment and ensure the normal operation of electronic equipment.


vinyl VMQ silicone
Silicone rubber products: widely used in various types of silicone rubber products, such as auto parts, medical supplies, etc. In automotive engine seals, vinyl VMQ silicone rubber can withstand high temperatures and mechanical stress and prevent oil leakage; in the medical field, it can be used to make products such as medical catheters, taking advantage of its good biocompatibility and mechanical properties.
Composite materials: Used as reinforcing materials to prepare composite materials. Vinyl VMQ silicone can form a strong bond with reinforcing materials such as fibers to improve the overall performance of composite materials, such as in some parts in the aerospace field.


Methyl MQ silicone and vinyl VMQ silicone have their own advantages in different fields due to their different structures and properties, meeting diverse industrial needs.