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What’s the Difference Between Thermoset Polymer and Thermoplastic?

 choosing between thermoset polymer and thermoplasticWhen you’re trying to choose the best kind of plastic for your new plastic mold you’re going to discover there are dozens of options to choose from. The plastics research phase can be quite confusing and overwhelming. The plastic you end up choosing for your new mold will depend upon the ways in which you’ll be using your plastic product or plastic component. The plastic material choice will also depend on the goals of your new mold. Without these details ironed out it’ll be much more difficult to decide which plastic and plastic process is best suited for your needs.

Two commonly used types of plastic include a thermoset polymer and thermoplastic. A lot of people confuse these two types of plastic due to name similarities. Below we highlight the crucial differences between these plastic types, as well as the style of final molds you can expect from using either thermoset Polymer and thermoplastic.

What Is A Thermoset Polymer?

A thermoset polymer is a type of polymer that sets, and cannot be changed, once it’s heated or cured. This kind of plastic cannot revert back to its original form after it’s been set. It also can’t be softened or changed. Essentially, you’re stuck with the final product once it’s been heated. That’s why it’s absolutely crucial you iron out every single detail with your mock-up and model, before you move onto mass production.

These kinds of molds are primarily used in automobile manufacturing, as they can be incredibly durable. They’re also used in certain inks, coatings, and adhesives.

What Is It Commonly Used For?

The most common form of a thermoset polymer is an automobile tire or a large truck tire. However, there are other common applications, which you’ll find below:

• Mattresses
• Cushions
• Home insulation
• Boat hulls
• Bathroom materials, like tubs and shower stalls
• Engine and helicopter blades
• Glues and adhesives
• Plywood
• Electronic coating
• Circuit boards and switches

As you can see this type of plastic has a very wide range of uses.

What Is A Thermoplastic?

A thermoplastic is a relatively weaker plastic that can soften when exposed to high heat, and can even be reverted back to its original form. Once this kind of plastic is heated it can be shaped by different molding processes, including, pressing, blow molding and injection molding, and pressing. A thermoplastic can be likened to an ice cube. It holds its shape once frozen but will melt and can assume many forms once it’s heated. This kind of plastic is very versatile and has a wide range of uses.

What Is It Commonly Used For?

Often, this kind of plastic is used in food packaging, as these kinds of plastics can be re-used and changed to fit many different needs. Some of the most common uses include, soft drink bottles and milk jugs, but there are other common uses, which we highlight below:

• Packaging film and wrap
Milk jugs and water bottles
• Housing wrap
• Car bumpers
• Carpet fibers
• Microwavable and storage containers
• Home siding
• Interior car panels
• Electrical cable covers

Choosing Between Thermoset Polymer and Thermoplastic

When choosing between thermoset polymer and thermoplastic, remember that thermoplastics are more pliable and can be re-used, but thermoset polymers are very rigid once heated and can’t be re-formed or molded once set.

If you’re looking for a plastic molding firm to help you conceptualize and produce your new plastic mold, then we hope you consider SPI industries. We’ve helped to produce a large variety of plastic molds across a diverse number of industries. If you have an idea for a plastic product or component that you want to bring to life, reach out to our team today.