May 14, 2026
Definition:General Purpose Plastics: These are plastics produced in large volumes, used in a wide range of common applications, characterized by good formability and low cost.
Engineering Plastics: These are industrial plastics designed for use as functional parts or durable housings. They offer superior strength, impact resistance, heat resistance, hardness, and aging resistance compared to general purpose plastics.
Key Differences
Types: The five most common general purpose plastics are polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polystyrene (PS), and ABS. These are all thermoplastics.Engineering plastics include polycarbonate (PC), polyamides (PA, nylons), polyacetal (POM), modified polyphenylene (mPPE), polyesters (PBT, PET), polyphenylene sulfide (PPS), polyarylate, and various thermosetting plastics such as unsaturated polyester, phenolic plastics, and epoxy resins.
Applications: General purpose plastics are typically used as non-structural materials. Due to their high volume and low cost, they are common in everyday items (e.g., PE, PP, PVC, PS, PMMA, EVA). Engineering plastics are used in demanding mechanical, thermal, and electrical applications where performance is critical.