Thermoplastics and thermosets are the two main types of plastic polymers commonly used in cable insulation. So what are the differences between these two insulating materials in terms of their chemical structure, properties and use?
Chemical structure
- Thermoplastic insulation:
1. It has a linear or branched molecular structure, which means that they can be softened and remolded when heated and regain their shape when cooled.
2. This process is reversible, so thermoplastic materials can be heated and cooled many times without changing their basic properties. As a result, thermoplastic materials are more sustainable and easier to recycle than thermosets. Also they melt at high temperatures but do not change chemically.
- Thermoset Insulation:
1.It forms a three-dimensional cross-linked network during the curing process, which prevents it from softening or melting when heated.
2.Once cured, thermosets have a permanent structure that cannot be reshaped by heat. This makes them difficult to recycle and reprocess. Also they decompose at high temperatures instead of melting.
Properties and Applications
- Thermoplastic insulation :
Due to their plasticity and reversibility, thermoplastic materials are easy to process, such as extrusion, injection molding and blow molding. They are widely used as insulation for wires and cables. e.g. PVC cables, PE cables, TPE cables. What’s more, thermoplastic materials usually have good mechanical properties and flexibility, but may not be as heat resistant as thermoset materials.
- Thermoset Insulation:
Thermosets require curing during processing, which is usually accomplished by heat or the addition of a curing agent. Once cured, they offer excellent heat resistance and chemical stability. Thermoset insulation is suitable for applications requiring high heat and chemical resistance, such as electric motors and transformers. The material is also used in XLPE cables and silicone rubber cables.
Choosing between thermoplastic and thermoset insulation really comes down to what you need for your project. Think about things like how much heat resistance you want, the mechanical properties, how easy it is to work with, and how eco-friendly it is.
