Plastic Injection Molding News & Case Studies

Injection Molding: Thermoplastics vs. Thermosetting Plastics

When it comes to injection molding, two main types of polymers are used: thermoplastics and thermosetting plastics. Even though they sound alike and share similarities, they have very different properties and are used in a variety of unique applications.

Thermoset Plastics & Thermoplastics: What’s the difference?

The main difference between thermoset plastic and thermoplastic is that thermoplastics can be reheated and reformed, while thermoset plastics can not be remelted and remain in a permanent solid state once set. Once thermoset plastics have been hardened, they become more resistant to high temperatures than thermoplastics. They cannot be melted down again to form a new shape, unlike thermoplastics which can be reheated and cooled multiple times to form different shapes.

Think of thermoplastics like cheese and thermoset plastics like a burger patty. Cheese comes in a variety of different shapes but when melted it can take on a new form. Once cooked, a burger patty can’t be melted to take on a new form – it can only be further charred, which can ruin the quality of the burger.

Thermoset vs. Thermoplastic: The Pros & Cons of Each

Thermoset Pros & Cons


  • Resistant to melting and higher temperatures
  • Highly flexible


  • Unrecyclable
  • Can NOT be reshaped or remolded

Thermoplastic Pros & Cons


  • Recyclable
  • CAN be reshaped or remolded
  • Highly impact resistant
  • Resistant to chemicals
  • More available finishing options


  • Can melt if exposed to extreme temperatures

Our Injection Molding Thermoplastics

We can work with almost any type of thermoplastic compound, but some of our most common thermoplastic polymers include:

  • Acrylonitrile butadiene styrene (ABS)

  • Polycarbonate

  • Polyethylene

  • High-impact Polystyrene

  • Polypropylene

  • Polymethylene

  • PVC

  • Nylon

  • Acrylic

  • Polyetherimide

Thermoplastic Injection Molding from UPM

With over 55 years of experience providing original equipment manufacturers and manufacturing businesses with premier plastic injection molding services, we have the expertise and the capabilities to help you choose the perfect thermoplastic polymer for your product. Are you looking for a partner that will work with you to reduce lead times and production costs without sacrificing quality? Then you’ve come to the right place. Get in touch with us to discuss your options today!

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