Slowly but surely, new developments in thermoplastic elastomers (TPEs) are providing alternatives to traditional rubbers. They can provide cost-effective, high performance replacements to EPDM, neoprenes and polyurethanes. Parts or items can be designed ergonomically with TPEs. Who can refuse a plastic part that offers good feel, comfort and easy control?
TPEs' popularity is understandable since they are processed like thermoplastics, yet perform like rubbers. That's no surprise. TPEs are two-phase blends system: a hard thermoplastic phase combined with a soft rubber phase. As Advanced Elastomer Systems (AES) puts it, "with TPEs like Santoprene, you can flex your imagination". No exaggeration indeed! Whether the soft-grip handle of MACH3 razor or the velvety, tactile feel of colourful Contura staplers - TPEs are taking the centre stage.
Another benefit of using TPE is that it can be overmoulded. For example, Kodak's Max Sport Fun Saver camera. A selected grade of TPE from GLS Corp. has been overmoulded onto polystyrene which provided the required waterproof seal. Many parts in the new Ford Focus (e.g., radiator air guides, under-the-hood clean air ducts, door inner waist seals, seat adjuster wheels etc.) have TPEs from AES which are overmoulded onto polypropylene or nylon. Recently, AES has claimed to have developed Santoprene 7000 grades that can tolerate as low as -800C by reducing glass transition temperature of TPE. However, TPE processing requires extra careincluding drying before use, heat exposure limits and proper training to moulders.
Many properties of TPEs must be cautiously judged in terms of their relative advantages over thermoset materials. If you are ready to toss your ideas, TPE material suppliers can turn them into profitable brand named parts.