Study of welding of poly(ether-ester) elastomers - Part I. Influence of contents of flexible segments on morphology and mechanical properties

Weldability of poly(ether-ester) (PEE) multiblock elastomers, which belong to the group of the thermoplastic elastomers (TPE), was investigated. Investigated PEE consisted of soft polyoxytetramethylene (FS) blocks and hard poly(butylene terephthalate) (RS) blocks; with the FS:RS ratio variable. Welds were prepared using the wire (rod) welding technique and extrusion welding. Optical and scanning electron microscopy were used to characterize weld morphology and their mechanical properties (elongation, bending, impact strength). Materials for the seams were not dried prior to welding, so hydrolytic degradation took place during welding (250-300 degreesC), visible particularly in PEEs with higher RS content, as shown by results of flow rate measurements (MFR). The investigations demonstrate that the PEE elastomers containing predominantly the PTMO rich soft phase are well weldable using the applied techniques, even when non-dried material is used for the welds.