liquid silicone rubber injection molding process
Medical silicone and food grade silicone differ in material properties, production processes, and application fields. The following are some key differences:
Material standards:
Medical silicone: produced according to strict standards in the medical industry, it needs to meet requirements such as biocompatibility and non toxicity, and often passes biocompatibility tests such as ISO 10993.
Food grade silicone: Products used in contact with food must comply with food safety regulations and standards, such as CFR Title 21 of the US FDA or EU Regulation No. 10/2011 of the European Union.
Raw material purity:
Medical silicone typically requires higher raw material purity to ensure its safety and reliability.
Although food grade silicone also requires high purity, it may not be as strict as medical grade in certain performance indicators.
Production process:
In the production process, both may use liquid injection molding (LSR), compression molding, or other processes. However, due to different uses, there may be differences in specific process parameters such as vulcanization temperature, time, etc.
Product type:
Medical silicone is commonly used in the manufacturing of medical device components, implants, and other products that require high cleanliness and stability.
Food grade silicone is commonly used in kitchenware, cooking tools, or products that come into direct contact with food.
Quality Control:
For medical grade silicone rubber products, quality control during the production process is stricter, including strict control of microbial contamination and requirements for sterile packaging.
For food grade silicone rubber products, strict hygiene conditions are also required during the production process to avoid contamination
Certification and Compliance:
Different countries and regions have different regulatory requirements for these two types of silicone rubber. Manufacturers need to obtain corresponding certifications and approvals based on the target market.
Difference in use environment: Due to different application scenarios, there may be specific demand differences in durability and anti-aging capability.
Due to the improvement of quality and safety standards, the use of higher grade materials may lead to increased costs
Understanding these differences helps in selecting suitable materials and developing appropriate processing techniques. If you are engaged in related research or development work, please choose the correct materials and technology path according to your specific needs, and always follow relevant industry standards for operation.
Different application fields: Medical silicone is mainly used in the medical field, such as artificial heart valves, meninges, breasts, joints and other medical implants, as well as medical catheters. Food grade silicone is mainly used in food related fields, such as food molds, pacifiers, kitchenware, household appliance sealing strips, etc.
Quality requirements: Due to the higher direct contact rate between medical silicone and the human body, the quality requirements are stricter. Medical silicone not only needs to comply with FDA certification standards, but also needs to be tested for biocompatibility and other aspects. Food grade silicone mainly requires food related certification.
There are significant differences in production process and performance requirements between medical silicone and food grade silicone. Understanding these differences helps us better understand the applications of these two materials in their respective fields and provides useful references for the development of related fields.

The design of silicone molds plays a crucial role in the molding process of silicone products. Silicone molds have had a profound impact on the structure, design, and quality of products. The following will discuss in detail how silicone mold design affects the molding of silicone products.
Firstly, the structural design of silicone molds directly determines the molding quality of silicone products. The rationality of the mold structure not only affects the appearance and dimensional accuracy of silicone products, but also relates to the overall quality and production efficiency of the product. For example, improper design of the mold closing line may cause tearing or deformation of silicone products during the molding process, seriously affecting the quality and aesthetics of the product. In addition, the design of the mold cavity is also crucial as it determines the shape and size of the silicone product. If the design is not reasonable, it may result in the product not meeting the expected shape or size requirements after molding.
Secondly, the design of silicone molds also affects the production efficiency of silicone products. A good mold design can make silicone products easier to demold, reducing downtime and scrap rates during the production process. At the same time, the design of the mold should also consider the convenience and safety of operation, in order to reduce the labor intensity of workers and improve production safety. In actual production, many silicone product manufacturers may experience low production efficiency or even unqualified products due to improper mold design.

Up to waterproof grade IP68 product accuracy ±0.02mm high prec

In addition to structure and design, the quality of silicone molds also has a significant impact on the molding of silicone products. High quality molds can ensure that silicone products have better fluidity and filling properties during the molding process, making the product molding more uniform and complete. Meanwhile, high-quality molds can also reduce wear and deformation during the production process, extending the service life of the molds. On the contrary, if the quality of the mold is poor, it may lead to defects such as bubbles and impurities in the silicone product during the molding process, seriously affecting the quality and appearance of the product.
In the design process of silicone molds, it is also necessary to consider the product’s usage environment and requirements. For example, for silicone products that require high temperature and corrosion resistance, the material and design of the mold need to be adjusted accordingly to ensure that the product can meet the usage requirements. In addition, for some special shaped silicone products, such as complex curved or thin-walled structures, the design of the mold also needs to be more refined and complex to ensure that the product can be successfully formed.
In addition, the molding process of liquid silicone products is also deeply influenced by mold design. Due to the low viscosity and high fluidity of liquid silicone, the exhaust design of the mold is particularly important. A good exhaust design can avoid the generation of bubbles and defects during the molding process, improving the quality and appearance of the product. Meanwhile, temperature control of the mold is also one of the key factors in the process of liquid silicone molding. By precisely controlling the temperature of the mold, it is possible to ensure that the liquid silicone gel solidifies uniformly in the mold, thereby obtaining high-quality silicone products.
Finally, it is worth noting that silicone mold design is not an isolated process. It needs to cooperate and coordinate with multiple aspects such as production technology, raw material selection, and production equipment. Therefore, when designing silicone molds, it is necessary to comprehensively consider various factors to ensure that the final designed mold can meet production needs and obtain high-quality silicone products.

Mim silicone encapsulation injection molding is a special manufacturing process that combines the characteristics of two materials to produce products with specific properties. “MIM” is the abbreviation for Metal Injection Molding, which is a process of mixing powdered metal with adhesive to form granular materials, which are then injected into the mold and solidified through an injection molding machine. Afterwards, degreasing and sintering steps are required to obtain the final dense metal components.

When this technology is used for silicone encapsulation, it means covering a layer of silicone adhesive on metal components that have already been made through MIM technology. Here are some key steps in this process:
Design phase: The design includes the structure of the inner core metal material part and the outer silicone covering part.
Material selection: Select suitable metal powders and adhesives for the MIM process, and determine the type of silicone suitable for the final product.
Preparation feeding: Mix metal powder with suitable adhesive to form granular materials that can be injected.
Injection molding: Using standard injection molding equipment to inject feed into precision designed molds to form the desired shape.
Degreasing treatment: Remove all adhesive components from cured but not fully hardened components.

Mim silicone encapsulation injection molding combines metal injection molding and silicone encapsulation technology

Sintering treatment: Heating the degreased components at high temperature to achieve full density and obtain the required mechanical properties of the metal material.
Cooling and cleaning: After sintering, the components need to be cooled and may require further processing or polishing to achieve precise dimensional requirements.
Prepare the encapsulation mold: Make or prepare corresponding silicone rubber compression or pouring molds for the silicone encapsulation process.

Silicone rubber injection/pouring/immersion coating and other operations:
If liquid silicone rubber (LSR) is used, it can be directly injected into the space containing rigid structural components.
If solid silicone rubber is used, it may involve molding or other methods to make it adhere to rigid structural components.
Vulcanization shaping: For certain types of silicone rubber, a vulcanization process is required after coating to ensure that its elasticity and other physical properties achieve the expected results.
Surface treatment: Necessary polishing, polishing, or other post-treatment processes are carried out on the surface according to product requirements to improve product quality perception and functional performance
Quality inspection: The final product needs to go through a strict quality inspection process to ensure that all indicators meet the standard requirements

This process is applicable to products that require both hard and wear-resistant properties, as well as good tactile or special insulation properties, such as the casings of some high-end electronic devices and medical equipment.

Silicone seals, as a high-performance sealing material, have been widely used in mechanical, automotive, aerospace and other fields due to their unique characteristics of high temperature resistance, low temperature resistance, corrosion resistance, and wear resistance. However, this article delves into the issue of whether the waterproof performance of silicone seals will be affected when used in high-temperature environments.

Silicone seals have excellent high-temperature resistance, and their softening temperature is usually above 200 ℃. This means that in general high-temperature environments, silicone seals can maintain their original elasticity and sealing performance. At the same time, silicone seals also have good thermal stability, and even if used for a long time under high temperature conditions, there will be no significant changes in physical and chemical properties, ensuring the durability of their sealing effect.

Although silicone seals have excellent high-temperature resistance, their waterproof performance may still be affected to some extent in extreme high-temperature environments. This is because high temperature environments can accelerate the aging process of silicone seals, leading to a gradual decrease in their elasticity and even the possibility of deformation or melting. Once the silicone seal loses its original elasticity, its sealing performance will naturally be affected, leading to a decrease in waterproof effect.

High temperature environments may also affect the adhesion between silicone seals and contact surfaces. Under high temperature conditions, the adhesion between the silicone seal and the contact surface may weaken, leading to a decrease in sealing performance. The weakening of this adhesion force may be due to changes in the wettability of the surface of the silicone seal caused by high temperature, or due to deformation or expansion of the contact surface at high temperature, making the silicone seal unable to tightly adhere.

In addition to the influence of high temperature environment on the waterproof performance of silicone seals, other factors may also have an impact on the waterproof effect. For example, factors such as environmental humidity, usage pressure, and construction operations may have a significant impact on the waterproof performance of silicone seals. In humid environments, silicone seals may lose their adhesion, thereby reducing their sealing performance. Excessive pressure or non-standard construction operations may also cause damage or deformation of silicone seals, thereby affecting their waterproof effect.

We can take some measures to reduce the potential impact on the waterproof performance of silicone seals in high-temperature environments. Firstly, when selecting silicone seals, full consideration should be given to their high temperature resistance and thermal stability, and products with higher softening temperatures and better thermal stability should be selected. Secondly, during the construction process, it is necessary to strictly follow the operating specifications to ensure that the silicone seal can tightly adhere to the contact surface and achieve the best sealing effect. In addition, for silicone seals that require long-term use in high-temperature environments, regular maintenance and inspection can be carried out to promptly identify and address potential issues.