Effect of the particle size on the viscoelastic properties of filled polyethylene

摘要: Abstract Composites of surface treated and non-treated colloidal calcium carbonate high-density polyethylene with different filler loading were prepared. Their viscoelastic properties studied by dynamic strain sweep small-amplitude oscillatory shear, compared to those the corresponding composites micron-sized calcite. The specific area enormously increases as average particle diameter becomes smaller than 600 nm, leading a strong tendency agglomeration (soft flocks) aggregation (hard clusters that need attrition be disintegrated). In nanocomposites, more stronger are formed in microcomposites due large contact between particles. have shapes maximum packing nearly spherical primary particles, thus enhance moduli viscosity composites. obtained results indicate higher nanocomposites is not direct consequence size but presence agglomerates aggregates. Clusters local structures do represent space-filling network low frequency region at high frequencies increase storage loss modulus. leads weak log moduli–log dependence (terminal) region. Polymer adsorption on particles' transient filler–polymer slow dynamics bound polymer, which contribute complex fluid. sum all these factors gradual shift crossover lower values. Above certain volume fraction, composite responds solid (storage modulus>loss modulus over whole range both independent terminal zone log–log plot).