Liquid Silicone Rubber Injection Molding (LSR) is an advanced molding process that takes advantage of the excellent characteristics of liquid silicone rubber (LSR), which is injected into the mold through an injection molding machine to form a solid product after vulcanization reaction. This technology is widely used in many fields such as electronics, medical, automotive, aviation, etc. With its high efficiency, precision and environmental protection, it has become an important part of modern manufacturing industry.
1. Liquid silicone injection molding principle
Silicone mixing: liquid silicone is usually mixed by component A (silicone body material) and component B (crosslinking agent, curing agent, etc.) in a certain ratio. Through the static mixer to ensure that the two are fully mixed.
Injection molding: The mixed liquid silicone is injected into the preheated mold at high pressure through the injection system of the injection molding machine to fill the cavities of the mold.
Vulcanization molding: In the mold, the liquid silicone gel undergoes a vulcanization reaction under heating conditions, transforming from a liquid to a solid state to form a rubber product with stable physical properties.
Demolding and post-processing: After the vulcanization is completed, the mold is opened to take out the product, and post-processing such as deburring and polishing is carried out to improve the appearance quality of the product.
2.Liquid silicone injection molding product production process
Mould preparation: choose the suitable mold according to the product requirements, and ensure the cleanliness and precision of the mold.
Raw material preparation: choose suitable liquid silicone raw materials and mix them evenly according to a certain ratio.
Injection molding: inject the mixed liquid silicone raw materials into the mold, through the control of the temperature and pressure of the injection molding machine, so that the raw materials in the mold fully flow and fill the cavity.
Vulcanization: Put the mold into the vulcanizing machine for vulcanization, so that the liquid silicone undergoes a chemical reaction to form a solid rubber product.
Post-processing: After vulcanization, take out the products for deburring, polishing and other post-processing to improve the appearance of the product quality.
3.Liquid silicone injection molding product customization process
Demand analysis: Communicate with customers to clarify the function, appearance, size and other requirements of the product.
Mold design: Design the mold according to the product requirements to ensure the precision and durability of the mold.
Raw material selection: Select the appropriate liquid silicone raw material according to the product usage and performance requirements.
Sample making: Make samples and test them to ensure that the products meet the requirements.
Mass production: mass production according to customer’s demand, and strictly control the temperature, pressure, raw material ratio and other key factors in the production process.
Quality inspection: quality inspection of finished products to ensure stable and reliable product quality.
4. Different liquid silicone injection molding materials
| Material | Key Characteristics |
| PDMS (Polydimethylsiloxane) | Transparent, colorless, can be cured into an elastic solid at room temperature, suitable for electronics, medical, and printing industries |
| Silicone Rubber | High elasticity, high-temperature tolerance, multiple hardness options available, suitable for various injection molding applications |
| Epoxy Resin | Chemically stable, high hardness, meets high-temperature, high-pressure, and high-speed injection molding requirements, durable |
5.Different liquid silicone injection molding product characteristics
| Product | Key Characteristics | Application Areas |
| Keypads | High elasticity, wear-resistant, waterproof, dustproof | Electronics |
| Seals & Gaskets | High temperature and low temperature resistance, chemical resistance | Automotive, Aerospace, Medical |
| Medical Devices | Biocompatible, non-toxic, easy to clean | Medical field, baby care products |
| Connectors | High electrical insulation, withstands repeated insertion and removal | Electrical engineering |
6.Different liquid silicone injection molding product differences
| Product Type | Shore A Hardness | Tensile Strength (MPa) | Tear Strength (N/mm) | Temperature Resistance Range (°C) |
| Keypads | 30-70 | 3.0-5.0 | 10-20 | -40 to +150 |
| Seals & Gaskets | 40-80 | 4.0-6.0 | 15-30 | -60 to +200 |
| Medical Devices | 30-60 | 2.0-4.0 | 8-15 | -40 to +120 |
| Connectors | 50-90 | 5.0-8.0 | 20-40 | -50 to +180 |
Liquid Silicone Injection Molding Service FAQ
Q: What are the advantages of liquid silicone injection molding?
A: Liquid silicone injection molding has the advantages of short molding cycle, high production efficiency, high product precision, good chemical stability, and excellent high and low temperature resistance.
Q: How to choose the right liquid silicone material?
A: When choosing liquid silicone materials, we need to make a comprehensive evaluation based on the use, nature and shape of the product to ensure that the material meets the performance requirements of the product.
Q: How to control product quality during liquid silicone injection molding?
A: During the liquid silicone injection molding process, key factors such as temperature, pressure, raw material ratios and mold precision need to be strictly controlled to ensure that the performance and appearance of the product is at its best.
Q: What are the application areas of liquid silicone injection molding products?
A: Liquid silicone injection molding products are widely used in electronics, medical, automotive, aviation and many other fields, such as the manufacture of keypads, seals, connectors, medical devices and so on.
Q: What is the customization process of liquid silicone injection molding service?
A: The customized process of liquid silicone injection molding service includes demand analysis, mold design, raw material selection, sample making, mass production and quality inspection.
