An organo-modified Boehmite (o-Boehmite) was used to prepare nanocomposite UV - curing coatings, based on a cycloaliphatic epoxy resin (3,4-epoxycyclohexylmethyl-3’,4’-epoxycyclohexane carboxylate). A hyperbranched polymer based on highly branched polyester, was also added to the resin, with the aim to modify its reactivity, such as a possible route to increase the toughness of the resin. Different amounts of the nanofiller and the hyperbranched polymer, ranging from 5 up to 20 wt.% of resin, were dispersed into the resin in the presence of triarylsulfonium hexafluoroantimonate, as a photoinitiator for the UV curing of the resin. The rheological behavior of the formulations produced was studied as function of the shear rate and of the content of each filler using a cone and plate rheometer. A general increase in viscosity was observed with increasing the volume fraction of each filler and a moderate pseudo-plastic behaviour was observed when o-Boehmite filler was added. A non-Newtonian behavior was observed with the incorporation of the hyperbranched polymer. The viscosity of the epoxy/boehmite resin mixtures was analyzed as function of the nanofiller volume fraction. In the case of epoxy/hyperbranched resin mixtures, the Cross equation was used to predict the viscosity of each formulation as a function of the shear rate and an appropriate relationship to predict the viscosity of each formulation as a function of the filler volume fraction, was determined.

Rheological characterization of UV - curable epoxy systems: effects of o-Boehmite nanofillers and a Hyperbranched polymeric modifier

ESPOSITO CORCIONE, Carola;FRIGIONE, Mariaenrica;
2009-01-01

Abstract

An organo-modified Boehmite (o-Boehmite) was used to prepare nanocomposite UV - curing coatings, based on a cycloaliphatic epoxy resin (3,4-epoxycyclohexylmethyl-3’,4’-epoxycyclohexane carboxylate). A hyperbranched polymer based on highly branched polyester, was also added to the resin, with the aim to modify its reactivity, such as a possible route to increase the toughness of the resin. Different amounts of the nanofiller and the hyperbranched polymer, ranging from 5 up to 20 wt.% of resin, were dispersed into the resin in the presence of triarylsulfonium hexafluoroantimonate, as a photoinitiator for the UV curing of the resin. The rheological behavior of the formulations produced was studied as function of the shear rate and of the content of each filler using a cone and plate rheometer. A general increase in viscosity was observed with increasing the volume fraction of each filler and a moderate pseudo-plastic behaviour was observed when o-Boehmite filler was added. A non-Newtonian behavior was observed with the incorporation of the hyperbranched polymer. The viscosity of the epoxy/boehmite resin mixtures was analyzed as function of the nanofiller volume fraction. In the case of epoxy/hyperbranched resin mixtures, the Cross equation was used to predict the viscosity of each formulation as a function of the shear rate and an appropriate relationship to predict the viscosity of each formulation as a function of the filler volume fraction, was determined.
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/11587/328136
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 36
  • ???jsp.display-item.citation.isi??? 33
social impact