Within the manufacturing industry, there are many different technologies that can be used to produce high quality, durable products. Liquid silicone rubber (LSR) injection molding is one technology that has gained popularity in recent years. This technology has transformed the production of multi-functional parts for industries ranging from healthcare to electronics, providing high quality and durable products. The process is characterized by its ability to produce silicone rubber products at high speeds. In this article, we will focus on outlining liquid silicone rubber injection molding temperatures and the LSR injection molding process.
What is the molding temperature for liquid silicone rubber?
The temperature at which liquid silicone rubber products are molded is determined by the nature of the product. Liquid silicone rubber injection molds are heated to approximately 250° – 300°. The metal or plastic substrate is then coated with CL-26AB adhesive and allowed to dry before being placed in the mold and heated. A calculated amount of liquid silicone for injection is injected into the hot mold through the gate and runner system. The silicone rubber is hot cured and molded at approximately 90°C-120°C. Within the temperature range of use, silicone rubber not only maintains a certain degree of softness, elasticity and surface hardness, but also has no significant change in mechanical properties and resists heat aging for a long time. If the design is correct, the liquid silicone rubber will be evenly distributed throughout the keyboard or component. The whole process will be a “closed loop” system. Finally, attention should be paid to the temperature, vulcanization time, exhaust air, equipment start-up, etc.
What is the ambient cure temperature for liquid silicone?
When it comes to curing liquid silicone, it depends on what the silicone material is. There are room temperature types and high temperature types. Room temperature can be cured in the natural environment; high temperature is generally about 150 degrees and a high temperature of about 180 degrees, a low temperature of 60 degrees, and the general temperature of silicone between -50 ℃ ~ 200 ℃.
The curing speed of organic silica gel is greatly affected by the ambient temperature. Suppose you need to speed up the curing speed according to your own conditions, appropriate heating, humidification or one-time reuse of unused adhesive. In this case, you must remove the nozzle front end of the glue curing before sizing!
How to achieve good curing performance of the product: Organic silicone curing uses the absorption of moisture in the air. Under the temperature conditions of 25°C and 50% R.H., the curing time needs more than 24 hours.
The curing conditions of one-component silica gel depend on temperature and humidity. With low temperature and humidity in winter, the surface drying and curing will be slower; with high temperature and humidity in summer, the surface drying and curing will be faster; liquid silicone curing at room temperature is generally around 25-60 degrees.
What is Liquid Silicone Rubber Injection Molding?
LSR injection molding is a robust and versatile technology that utilizes the unique properties of liquid silicone rubber injection molding to produce a variety of parts with complex geometries. This thermoset process cools the material delivery system while heating the mold to cure the silicone material into the part.
The liquid silicone injection molding process offers a high degree of automation and short cycle times and can reduce the price of silicone parts. The process uses a closed-loop system to increase productivity and minimize the risk of contamination. In addition, parts are biocompatible and can be sterilized. This is critical for industries such as healthcare.
Liquid silicone injection molded parts are elastic and highly resistant to chemicals, electricity and heat. As a result, liquid silicone injection molding technology has become common in the production of medical devices, automotive parts and consumer products.
LSR Molding Process Flow?
The liquid silicone rubber injection molding process is a multi-step process. The liquid silicone is supplied in 2 drums, A and B. The viscosity of the silicone allows it to be pumped through a hose using a metering pump. The pump also ejects a specified amount of material pigment, which gives the silicone its specified color when mixed with the silicone. The materials are then mixed and, when complete, form a uniform, consistent material throughout the part. The curing process begins when the material in barrel A is mixed with the material in barrel B. The material is then drawn into the barrel and cured. The material is then pulled back into the barrel and prepared for injection.
If you have any questions or concerns about how liquid silicone injection molding can improve your product, please contact our office at [email protected] or request a quote here. We are located in Shenzhen, China and all manufacturing is done locally.