A new patented chemical foaming agent (CFA) masterbatch from Polyfil Corp., Rockaway, N.J., utilizes Vistamaxx 6102 PBE (propylene-based elastomer) from Houston-based ExxonMobil Chemical as the carrier, which is said to broaden opportunities in the production of foamed PP sheet and thermoformed parts, allowing part manufacturers to quickly manufacture lightweight, strong products.
Recent tests performed by Polyfil, have shown that a foamed sheet using the new Ecocell VM1 CFA with the Vistamaxx carrier compared to typical carriers such as LDPE and PE copolymers, produces lightweight, strong and flexible products. Vistamaxx can be compounded at lower temperature than the other carriers which makes it well suited to incorporating specialty additives that are shear- or heat-sensitive. In thermoformed microwaveable bowl applications using Ecocell in PP foamed sheeting was shown to result in two advantages: Compared to foamed sheets in which Vistamaxx was not used, it reduced cycle times and decreased thermoforming temperatures by as much as 200 F from typical oven temperatures, leading to a 25% reduction in energy usage.
Moreover, whereas the thermoforming process removes around 8% of the cells from the foam, using Vistamaxx in the foaming agent not only reversed this loss of density, but actually boosted foam content by about 10%. The result is a product that can be 30% lighter and may use 25% less polymer than a foamed PP sheet that does not use Vistamaxx with the foaming agent. “We see excellent improvements when we add 1.5%-3.5% Vistamaxx as a carrier resin. Vistamaxx can be successfully integrated into processing and production. Once the process is dialed in, it is easy to replicate,” says Polyfil’s foams technology manager Renee Lapierre. (281) 870-6600 • exxonmobil.com; (866) 765-9345 • polyfil.com