Application of vacuum casting technology for manufacturing of polymeric gears prototypes

In this study, the nanocomposites based on two-component polyurethane resin RenPIM-VG 5286 (PUR) with added nanofillers Nanobent® ZR1 and ZR2, previously modified with octakis(tetramethylammonium)octasilsesquioxane and octakis{3-[N-(hydroxyethyl)dimethylamino]-propyl}octasilsesquioxane, were examined for application to vacuum casting technology (VC). The reactivity of the molding compositions (gel time and maximum curing temperature) as well as their thixotropic properties, which have an important impact on the technology process of prototyping gears in silicone matrices, were investigated. The effect of nanofiller type on the functional properties of the resulting composites was also determined. It was demonstrated that by introducing the hybrid filler system, a reduction in radial and axial shrinkage was achieved, which led to a radical improvement in the dimensional stability of gear castings.