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How does blending EPDM with polypropylene produce a thermoplastic elastomer?

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Know how researchers created a synthetic material, elastomers, that can change color and texture to specific voltage change, like that of cephalopods — elastomer Learn about elastomers that are changeable in colour and texture, much like the skin of octopuses and other cephalopods. In the elastomers, these changes take place under electrical stimulation.

Thermoplastic elastomers, such as the trademarked product Santoprene, are produced by creating a heterogeneous blend of ethylene-propylene-diene monomer (EPDM) and polypropylene.12

Because these polymers are molecularly incompatible, they form a fine, heterogeneous mixture where the materials remain as separate, small regions. During the mixing process, the EPDM component is chemically interlinked to form a rubbery solid.1

This combination results in a material that functions as a thermoplastic elastomer because:
* Processability: The polypropylene component becomes soft and fluid at high temperatures, allowing the mixture to be molded and remolded like a plastic.12
* Elasticity: The interlinked EPDM provides rubbery, elastic properties.13
* Durability: The blend benefits from the inherent resistance of EPDM to oxidation, ozone, and weathering.23

While these blends are not as springy as conventional covalently interlinked elastomers, their ability to be recycled and easily processed makes them highly useful for applications like flexible covers, sealing strips, and footwear.123