Not all plastics behave the same under heat or pressure. If you’re designing plastic parts, understanding the difference between thermoplastics and thermosets is essential. This guide explains how they differ in behavior, performance, and ideal use cases.
Can be melted, reshaped, and reused multiple times
Soften when heated, solidify when cooled
Common types: ABS, Nylon, Polycarbonate, PET, PP
Processes: injection molding, extrusion, thermoforming
Key traits:
Recyclable
Flexible
Cost-effective for mass production
Melt at defined temperatures
Irreversibly cure when heated or chemically set
Cannot be remelted or reshaped
Common types: Epoxy, Phenolic, Melamine, Urea-formaldehyde
Processes: compression molding, resin casting
Key traits:
Heat and chemical resistant
Rigid and durable
Stable under load and temperature
Not recyclable after curing
1. Reusability
Thermoplastics: Yes
Thermosets: No
2. Behavior Under Heat
Thermoplastics: Melt when heated
Thermosets: Remain solid, no melting
3. Flexibility
Thermoplastics: Often flexible
Thermosets: Hard and brittle
4. Performance
Thermoplastics: Moderate strength, good ductility
Thermosets: High strength, great dimensional stability
5. Use Cases
Thermoplastics: Consumer goods, toys, automotive covers
Thermosets: Electronics, adhesives, aerospace parts
Use thermoplastics when:
You need recyclable or reprocessable parts
The design needs flexibility or ductility
You require fast production cycles
You’re producing in high volume
Examples:
Bottles
Medical casings
Packaging
Lightweight enclosures
Use thermosets when:
Components must withstand high heat or chemicals
Structural integrity over time is critical
You need superior rigidity and dimensional accuracy
Examples:
Circuit boards
Engine parts
Electrical housings
Adhesives
Thermoplastics
✅ Reusable
✅ Meltable
✅ Flexible
❌ Lower heat resistance
Thermosets
❌ Not reusable
✅ Heat-resistant
✅ Strong and rigid
❌ Cannot be remolded
At Ekinsun, we provide machining and production services for a wide range of plastic materials. Our team helps you select the ideal polymer—whether it’s thermoplastic for flexibility or thermoset for performance.
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