The effect of small amounts of nanoparticles on the melt-state linear viscoelastic behaviour is investigated for different polymer-nanoparticles model systems characterized by poor polymer-particles interactions and low particle contents.contents. The drastic increase of the rheological properties with respect to the matrices is related to the formation of a filler network above a critical particles volume fraction. Once formed, the filler network exhibits an elastic feature that mixes with the intrinsic viscoelastic response of the polymer matrix, resulting in a complex Φ- and ω-dependent viscoelastic response of the nanocomposite. However, we show that the contributions of filler network and suspending medium can be decoupled due to the weak polymer-particle interactions and the differences in temporal relaxation scales. The adopted approach is validated through the building of a master curve of the moduli, which reflects the scaling of the elasticity of composites along the viscosity of the suspending medium. The two-phase model well works irrespective of the structure of the filler network, making evident the strict interrelationships between the structure, both on nano- and micro-scale, and the melt- state behaviour of the studied PNCs.

Dynamics of Nanoparticles in Polymer Melts

FILIPPONE, GIOVANNI;ACIERNO, DOMENICO
2012

Abstract

The effect of small amounts of nanoparticles on the melt-state linear viscoelastic behaviour is investigated for different polymer-nanoparticles model systems characterized by poor polymer-particles interactions and low particle contents.contents. The drastic increase of the rheological properties with respect to the matrices is related to the formation of a filler network above a critical particles volume fraction. Once formed, the filler network exhibits an elastic feature that mixes with the intrinsic viscoelastic response of the polymer matrix, resulting in a complex Φ- and ω-dependent viscoelastic response of the nanocomposite. However, we show that the contributions of filler network and suspending medium can be decoupled due to the weak polymer-particle interactions and the differences in temporal relaxation scales. The adopted approach is validated through the building of a master curve of the moduli, which reflects the scaling of the elasticity of composites along the viscosity of the suspending medium. The two-phase model well works irrespective of the structure of the filler network, making evident the strict interrelationships between the structure, both on nano- and micro-scale, and the melt- state behaviour of the studied PNCs.
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11588/416924
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact