Effects of volume fraction, size and geometry of different fillers on interparticle interactions in LDPE melts

Abstract

This study focuses on the effects of volume fraction, size and geometry of different fillers on interparticle interactions in low-density polyethylene (LDPE) melts. For this purpose, the rheological properties of LDPE filled with various fillers have been investigated by means of high pressure capillary rheometry in consideration of different particle sizes. It has been shown that interparticle interactions vary depending on volume fraction of the fillers. Furthermore the aspect ratio of the particles has a great impact on tendency of particles to interact with one another. While fibrous and flake shaped particles have a great tendency to interact with one another, spherical particles, depending on the particle size, exhibit a transition from negligible to non-negligible interactions. It has been shown that on the basis of a generalized interaction function, that considers the transition from negligibly interactions to the domain of pronounced interactions, interparticle interactions can be taken into account mathematically for describing the flow behaviour of particle filled LDPE melts.