Eurostar EP sources its fillers through Univar-France, the distributor in France for "eco-mineral specialist" RockTron. We have reported on RockTron and its novel fillers before. In an interview at last fall's K show in German, RockTron (Bristol, UK) director of advanced products, Godfrey Short, gave details of his company's Mintron 7 eco-filler, which comprises solid alumino-silicate glass spheres derived from fly ash. The 7-µm particles are grayish in color but Short notes that 80% of plastic automotive components are black, and this is one market segment that the filler targets.
"Mintron 7 does not compete with low-cost calcium carbonate filler," said Short. "We aim to compete with synthetic glass spheres." These manufactured glass spheres can cost up to $2000 per tonne but Short believes that cost-competitive Mintron 7 may expand utilization of glass spheres beyond niche applications. Besides reinforcing, the glass spheres also prevent warping in thick sections and ensure controlled dimensions. Scratch tests have also indicated that Mintron 7 is a good replacement for talc in filled PP. Mintron 7's density, averaging 2.2, is also lower than the 2.7 of talc. The fillers can be used in thermoplastics and thermoset plastics.
At Eurostar EP, the compounder's new grade, Starpylen ECR30K ECR: PP 30% glass bead reinforced, contains 30% MinTron.
RockTron claims its production technology for the fillers is unique in that it is the only technology that can transform both fresh and stockpiled fly ash waste into fillers for commercial use, reducing an energy utilities' impact on the environment.