Injection molding polyurethane, TPU and TPE

UW-ELAST manufactures products with fantastic properties using injection molded thermoplastic elastomer (TPE) and thermoplastic polyurethane (TPU). 

Injection molding of TPE and TPU, as well as other thermoplastics, is done so that raw material in solid form is melted to be injected into a mold under high pressure and in a short time.

With injection molding, we can manufacture small to medium-sized parts with high demands on material properties that can be manufactured in very long series. We also offer solutions for metal replacement. UW-ELAST AB today offers injection molding in our production unit in Traryd. There are currently four injection molds with 35 to 100 tons of locking force.

Examples of injection molded products are protective nose, plastic parts etc.

Production methods

Extreme deformation of TPU part. Thermoplastic polyurethane today has deformation properties that are very close to hot cast polyurethane. This part was originally made of hot cast polyurethane and is now made of TPU. The test was performed at room temperature and at -35 ° C.

When to choose injection molding?

There are some differences between molding and injection molding when looking at the material. When casting, a thermosetting plastic is used, a polyurethane that becomes tough and durable by crosslinking. When injection molding, we mainly use thermoplastic polyurethane that is not crosslinked. It is not a question of several components or a curing process. Instead, injection molding takes place when the polyurethane is melted and the product then solidifies when the polyurethane cools. The thermoplastic can be recycled and melted down again, while thermosets cannot be recycled in this way.

The transition from, for example, molding with thermoset to molding with thermoplastic often takes place as a natural step when manufacturing volumes increase. The shift in materials can mean some lost material properties, but the cost of production drops significantly.

About TPU

TPU is an injection-moldable urethane-based thermoplastic that has a number of fantastic properties thanks to the combination of high abrasion resistance (wear resistance), tear strength and elasticity. As a construction material for, among other things, industry, TPU solves the most complex problems in combination with being very cost-effective. Today, we injection mold TPU quality between 70 shore A and 75 shore D. Injection molding with TPU is very different from injection molding with other thermoplastics.

Thanks to our experience and our willingness to always deliver both at the best price and with optimal delivery time, we know when it is appropriate to suggest injection molding as an alternative. In general, the method is best for smaller details in long series, which for us means 1,000 details or more.

Do not hesitate to contact us if you have questions about injection molding.