The Opportunity

The customer was experienced and knowledgeable with injection molding unfilled PP (polypropylene) resins, but they were expanding into a new market with a new product and needed formulation assistance. The customer’s preference was to continue using PP for the cost performance of the material, but PP by itself did not provide the product stiffness that was required by the application.

The Approach

Our overall approach was to add filler to stiffen the product with the goal of simultaneously not sacrificing other properties, especially impact strength. We started with a PP resin like what was currently in use by the customer and then did a filler screening study by adding different fillers at a range of loading levels. Looking at physical properties, the loss of Izod impact strength that accompanied the inclusion of filler was not acceptable, so we modified the compound by adding some elastomeric resin to the PP and filler.

The Outcome

By modifying the resin system and adding filler, we were able to create a PP based compound that met all the customer’s physical property requirements for their new product. The compound was as easy to mold as unfilled PP resin, so the manufacturing did not experience any loss in efficiencies with the new compound and the product ultimately had a successful launch.