Chemorheological study of phosphorylated flame retardant epoxies

Kam Chuen Yung, J. Wang, Tai Man Yue

Research output: Journal article publicationJournal articleAcademic researchpeer-review

2 Citations (Scopus)

Abstract

The aim of this work is to study the chemorheology of the phosphorylated novolac epoxy used in flame retardants. The rheological properties are measured by a parallel plate viscometer and are combined with the kinetics of the curing reaction to explore the conversion dependent character of the viscosity. It was found that dynamic viscosity is a unique function of the effective shear rate over a wide range of frequencies and strains after being corrected for temperature. The effective shear rate dependence of the viscosity is described with a power law with an exponent that depends on the conversion. The effect of temperature is described with an Arrhenius type equation with conversion dependent parameters. Differential scanning calorimetry was applied to determine the kinetic equation that is used, in combination with the thermal history, to obtain the conversion during the rheological measurements. Time-cure-temperature modelling was applied to study a variety of factors that had an influence on the chemorheology. It was also found that the Cox-Merz relation can be utilised to correlate the dynamic viscosity data to the shear viscosity data. The Castro-Macosko model is proposed when considering the combination effects of shear thinning viscosity and reaction kinetics.
Original languageEnglish
Pages (from-to)25-31
Number of pages7
JournalPlastics, Rubber and Composites
Volume40
Issue number1
DOIs
Publication statusPublished - 1 Feb 2011

Keywords

  • Chemorheology
  • Cox-Merz relation
  • Flame retardant
  • Phosphorylated epoxy
  • Time-cure-temperature modelling

ASJC Scopus subject areas

  • Ceramics and Composites
  • Chemical Engineering(all)
  • Polymers and Plastics
  • Materials Chemistry

Cite this