Liquid silicone materials lend a lot of flexibility to the liquid injection molding process, which is what we rely on here at Si-Tech. That’s because it, among other things, has high heat and flame resistance so it can stand up to temps of more than 250°C, and even as low as -90°C. Because silicone is also very malleable and pliable, you can easily achieve transparency or coloring in the finished product if necessary.
Doesn’t matter which industry you’re in — automotive, defense, medical, aerospace, textile, food, electronics, or appliances – your business can benefit not only from silicone molding methods but from rapid prototyping as well.
In the process, silicones and acrylics are used, featuring a spring-loaded pin nozzle. This helps to avoid machine’s hardware from getting backed up or clogged. One plunger will hold the base to make plastic, while the other has a catalyst — both of which are added to the static mixer.
The liquid mixture is then injected into the desired mold, heated up to between 355 and 390 F. Once it’s sufficiently hardened, the materials are brought to their melting points. After that, a cooling period takes place. Voila – you have your finished product.
Three Main Methods
The three top methods utilized in the silicone molding process include casting, compression molding and injection molding. The first step is to offer a mock up to the client. This is a representation featuring handcrafted parts or sketches taken from preliminary testing as well as refinement of concepts. Generally, there are no details in this stage.
Then, we offer a rough, working prototype to start finalizing materials and identifying a general form. Finally, we offer a functional prototype, molded into the material with extreme dimensional accuracy.
Silicone Compression Molding
This is our most common process, and it involves the use of labor-intensive silicone rubber. It’s basically a pre-catalyzed product that can be made by adding powder. This helps it cure during heat application. We add pigment to the silicone with a two-mill roll. After the material is pre-catalyzed with pigment added, it is weighed and shaped to match specifications.
The material is placed into the mold cavity which thereby compresses the rubber between the top and bottom plates. Those plates are heated to melt and then cure the silicone. Compression molding is a basic and simple form of silicone rubber molding.
Contact Si-Tech
Si-Tech uses silicone for its pliability and flexibility. To learn more about our many silicone molding processes, contact us at 757-887-8488.
