Choosing Double Shot Mold Materials for Heat and Chemical Exposure

Selecting materials for a double shot molded part that will encounter elevated temperatures or chemicals requires testing the specific grades under real operating conditions. The available product information lists ABS+TPU and PP+TPE as compatible hard-and-soft combinations, but does not provide ratings or comparative results for either exposure type.

What the Available Specifications Tell You

Longterm’s double shot molding information confirms support for ABS+TPU and PP+TPE. It does not identify one pair as more suitable for heat or chemical contact, nor does it state temperature limits or chemical compatibility. Material names alone are not enough to establish service performance.

How to Evaluate a Material Pair

Start by documenting the part’s expected temperature range, duration of exposure, chemicals involved, and any relevant cleaning or operating cycles. Then confirm the exact resin and elastomer grades with the supplier. Request material-specific test evidence where available and agree on sample-approval criteria before tooling or production decisions are finalized.

The listed inspection process covers mold trials, dimensions, and pre-shipment checks. The product information does not state that these checks include heat-aging or chemical-compatibility testing, so those evaluations should be requested separately when they are necessary for the application.

Tooling Details and Application Context

The mold is described as a two-color injection structure with high-precision alignment and optional multi-cavity configurations. Listed mold steel grades are 718H / 1.2738, and the stated mold life is up to 800,000 shots. These are tooling specifications; they do not define the service limits of the finished ABS+TPU or PP+TPE part.

Potential applications mentioned include consumer-electronics shells and household-appliance housings. Longterm also reports a double shot overmolding mold project for a consumer-electronics shell supplied to a customer in France, where feedback noted good alignment and stable trial samples. This illustrates tooling experience, but the reported case does not establish resistance to heat or chemicals.

Frequently Asked Questions

Which combination is more resistant to heat and chemicals?

The supplied specifications do not compare these properties. ABS+TPU and PP+TPE are both listed as compatible combinations, but neither can be identified as the better choice without grade-specific evidence and testing.

Are heat and chemical tests included in the listed inspection steps?

No. The stated checks are a mold trial run, dimensional testing, and pre-shipment inspection. Confirm whether additional exposure testing can be arranged for your application.

What should be settled before placing an order?

Confirm the precise material grades, expected exposure conditions, and sample test requirements. The listing states a minimum order of one mold set and a lead time of 25–40 days.

Recommendation

Both ABS+TPU and PP+TPE are presented as options for double shot molding, but the available information does not establish their suitability for any particular heat or chemical environment. Select a pair only after reviewing material-specific data and validating representative molded samples against the intended conditions. Longterm offers custom double shot overmolding molds, online technical support, and a one-set minimum order. For technical details, contact rogerluo@longterm-mold.com.

About Longterm

Longterm Manufacturing Solutions Limited was established in 2010 and serves customers in the United States, Europe, Australia, and other markets. Its 50-person team includes seven experienced engineers and provides mold design, tooling, precision machining, mold manufacturing, and parts production. The company holds ISO 9001:2015 certification.