PC/ABS Substrate with TPE Overmold

Earlier in 2023, Hawkeye Molding was working with one of our partners on a new product launch. The project required substrate parts that had a UL 94 V-0 flammability rating. We decided we would use a PC/ABS material that we have used successfully on other projects that have a V-0 UL 94 requirement. The other aspect was we needed to overmold a soft-touch screen enclosure for an electronics monitor that was part of the assembly. It was important to choose a material that would perform to our partner's liking but would bond effectively to the molded substrate.

When choosing the best TPE material for an injection molding overmolding application with a PC/ABS substrate, there are several factors to consider. Here are some key steps to follow:

1. Determine the required properties: First, you need to identify the specific properties required for your application. This might include factors such as hardness, flexibility, resistance to chemicals or UV light, and more. Knowing these requirements will help you narrow down your material choices.

2. Consider compatibility: The TPE material you choose must be compatible with the PC/ABS substrate. This means it should adhere well to the substrate during overmolding and maintain good adhesion over time.

3. Evaluate processing requirements: Different TPE materials have different processing requirements, such as temperature and pressure settings. You need to ensure that the material you choose is compatible with your injection molding equipment and processes.

4. Review available materials: Once you have identified your requirements and evaluated the processing needs, you can review the available TPE materials. Some commonly used TPE materials for overmolding applications with PC/ABS substrates include:

- Styrenic block copolymers (SBCs): These materials offer good adhesion to PC/ABS substrates, along with excellent flexibility, elasticity, and resistance to UV light.

- Thermoplastic polyurethanes (TPUs): TPUs are known for their excellent abrasion resistance, flexibility, and toughness. They can be used for overmolding applications with PC/ABS substrates, but may require additional adhesion promotion.

- Thermoplastic vulcanizates (TPVs): TPVs offer good adhesion to PC/ABS substrates, along with excellent elasticity, durability, and resistance to chemicals and UV light.

5. Test the material: Before committing to a particular TPE material, it's important to test it in your specific application. This can help ensure that it meets your requirements and performs well over time.

By following these steps, you can choose the best TPE material for your injection molding overmolding application with a PC/ABS substrate.