Materials News

New TPVs for weather seals

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The company says the TPV grades exhibit a low dynamic viscosity, which results in enhanced flow over a wide range of shear to produce moulded seals with excellent surface appearance and no flow marks.

Processability is also said to be improved as the injection pressure can be reduced by about 30-40%, allowing for less risk of part warping, making it easier to set process conditions and mould design.

Furthermore, injection temperatures can be lowered by 10ºC and shorter cycle times are possible, depending on part size and wall thickness. This may lead to sustainability benefits through less glass breakage and lower energy consumption, along with the fact that TPVs are also fully recyclable. In addition, cost savings are possible due to simplified processing and reduced cycle times.

The higher gloss levels of the TPV grades is said to increase design flexibility and specific mould graining can be used to match the surface aspect of extruded profiles. The grades are also said to offer compression and tension set comparable to EPDM rubber, and exterior UV-resistance that meets OEM specifications. Requiring lower injection pressure, the new TPV grades are also said to be less sensitive to flow direction during moulding.

Available in two hardness levels, 60 Shore A and 75 Shore A, the TPVs can be used as a drop in replacement for existing materials.