A thermoplastic, or thermoplastic resin, is a type of polymer material that becomes pliable and moldable when heated above a specific temperature and that hardens into a solid when cooled. Most varieties of thermoplastic resin are recyclable and can be reheated, reshaped, and reused repeatedly.
Thermoplastic resins used for composite structures are divided into two types: Amorphous and Semi-crystalline. Resin selection is typically based on cost and specific performance requirements.
Compared to thermoset resins, there are two major advantages of thermoplastics in composites. The first is that many thermoplastic resins have an increased impact resistance compared to comparable thermoset materials. In some instances, the difference is as high as 10 times the impact resistance.