Structure-properties relationships of iPP based filled with spherical calcium carbonate nanoparticles

Isotactic polypropylene (iPP) based nanocomposites filled with calcium carbonate nanoparticles (CaCO3) were prepared by melt mixing and their structure-properties relationships were studied. Spherical CaCO 3 coated with two different coating agents, polypropylene-maleic anhydride graft copolymer (iPP-g-MA) and fatty acids (PA), as nanoreinforced phases (C-PPMA and C-PA, respectively) were tested. The influence of nanoparticles surface treatment on the polymer/ nanofillers interfacial adhesion and on the final materials properties was also investigated. The morphological analysis has allowed defining two types of coating agents: a non-interacting agent (PA) and a coupling agent (iPP-g-MA), able to induce different iPP/nanofiller adhesion degrees. Moreover Young's modulus increases almost linearly with C-PPMA nanoparticles while a slighter improvement was recorded for iPP/C-PA nanocomposites. The iPP thermal stability is also improved by the presence of nanoparticles. Pinally, CaCO 3 drastically reduces the iPP permeability to both oxygen and carbon dioxide.