| The purpose of this study was the development of elastomeric TPO compounds by blending plastic materials with elastomeric materials. The compound developed had intermediate properties between thermoplastic elastomers and thermoplastic olefins. The particular application of this material is in vehicle interior skins. The components evaluated in the new material were polypropylene (PP), an elastomer (poly alpha-olefin), and a third resin, which was varied. A detailed design of experiments for the formulation material was carried out to understand the effect of different components on the end compound. The material variable considered for the design of experiments was the ratio of entangled resin to elastomer. The resulting compounds were evaluated for rheological, tensile, hardness and surface energy properties. These properties were used to rank the compounds based on a number of end-use criteria such as paintability, soft feel and thermoformability. It was seen that with an increase in temperature there was significant reduction in the tensile properties. Esurlyn 8528 and Esurlyn 9520 showed melt fracture shear rates to be significantly high even at lower temperatures. Surface energy results indicated Dupont to be the best material for paintability applications. Based on mechanical, thermal, bondability, and hardness testing criteria, Esurlyn 8528 was found to be the best overall material for the application. |
