Vistamaxx elastomer gains traction in a variety of markets

Fairlawn, OH—Using a variety of end markets, including consumer goods, construction, and recycling, ExxonMobil Chemical recently displayed the growing variety of applications that can benefit from its propylene-based Vistamaxx elastomer. As part of the company’s recent Elastomer University, market developers Chuck Siskovich and Jeff Smith walked through a variety of applications that have used Vistamaxx to improve everything from impact resistance to clarity and flexural modulus.

In the renewable energy market, the company also announced that it has two new Santoprene thermoplastic vulcanizate (TPV) grades that have been UL-rated flame resistant. Santoprene TPV 251-70W56 and 151-70W56 could see use in low-voltage wire/cable applications, molded insulators, motor mounts, and strain relief, allowing OEMs to consolidate parts by combining insulation, enclosures, and sealing functions in one component (more on Santoprene TPV 251-70W56 and 151-70W56 in coming weeks).

For many of the Vistamaxx applications, the elastomer was dry blended as a “drop-in modifier” at the injection molding machine in concentrations 5-10%. In a clear box cover and transparent plastic tote, Vistamaxx 6202 propylene-based elastomer was added to a random copolymer polypropylene (RCP) retain clarity and impact strength. In the case of the plastic tote, the customer, which declined to be identified, had been using a styrene ethylene butylene styrene (SEBS) elastomer. It had considered switching to a plastomer, but found the impact on transparency to be too high, and eventually settled on adding Vistamaxx in concentrations from 5-10%.

The company also touted the elastomer’s utility in DVD cases, imparting greater impact and elimination of stress-whitening, without the need for new tooling, as well as a food container lid, where it replaced a homopolymer PP, which had reduced clarity, with a RCP loaded with 5-10% Vistamaxx. In addition to boosting flexibility, which eased opening and closing of the lid, the elastomer improved living-hinge performance.

In terms of wholly new applications that allow plastics to replace competitive materials in some instances, ExxonMobil Chemical laid out an array of product targets in the construction market. In a bid to replace tar-paper-based roof underlays, or plastic ones that don’t have sufficient grip to hold to steep roof angles, the company is promoting homopolymer PP sheeting that is extrusion coated with Vistamaxx. The resulting sheet’s higher coefficient of friction helps it hold to steeper roofs, while also being less slippery to walk on.

ExxonMobil Chemical also shared a thermoplastic olefin (TPO) modified roof sheeting that uses Vistamaxx to increase flexibility by up to 35%, easing its installation and repair. The company says the elastomer also increased the welding window by 14%; lifted seam strength 30%; and boosted peel strength by 17%. Also in the construction market, the company displayed an sound-deadening application, which used a calcium carbonate/Vistamaxx compound. In this instance, Vistamaxx is the carrier resin loaded up to 70% with calcium carbonate while retaining good flexural modulus (67 MPa).

In the recycled polymers market, ExxonMobil Chemical has found that Vistamaxx helps accommodate the inconsistencies of materials inherent in many recycling streams. The addition of the elastomer to reclaimed resin has been shown to increase impact strength at low temperatures, among other benefits. —Tony Deligio