Nucleation efficiency of talc in the foaming behavior and cellular structure of polyolefin-based foams: new perspectives for optimized lightweight materials

Abstract

The research consisted in evaluating the nucleation efficiency of different types of talc (with different particle size distributions, morphologies and even surface modifications) in the foaming behaviour and cellular structure os polypropylene-based materials, with the objective of developing lightweight materials with improved stiffness and lower densities. Nucleation efficiency was first evaluated in talc filled PP foamed with a physical blowing agent inside a high pressure vessel. Depending on different talc characteristics, such a particle size distribution, surface area and morphology, cell density as much as doubled. Optimized foamed PP-talc composites prepared by injection-moulding using the MuCell process displayed further weight reductions for similar stiffness values.