Coalescence and curing and their measurement in chip seal emulsions

One of the objections to the use of emulsions in chip seal applications is the difference in cure times between bitumen or cutback seals. This opinion is often associated with the notion that water must evaporate or the seals must “dry” to create initial strength. The cure characteristics of an emulsion are dependent on many factors associated with the physical form and the chemical composition of the emulsion. The rate at which films form as the emulsion is breaking has a significant influence on initial seal strength. This in turn is controlled by coalescence rate and mechanism of the emulsified binder. This paper discusses work carried out on emulsion formulation, particularly particle size and particle size distribution and emulsifier selection on film formation. Tests have been developed to measure cure rate under a range of conditions including humidity and temperature and to compare systems with different aggregates. Test work was carried out in New Zealand but also USA and Russia. It is concluded that emulsion cure can be controlled to optimise performance even under poor conditions such as high humidity and cool temperatures. Formulation of emulsions with additives to promote film formation is possible. (a)

  • Authors:
    • HOLLERAN, G
    • MOTINA, I
  • Publication Date: 2006-10

Language

  • English

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 01054946
  • Record Type: Publication
  • Source Agency: ARRB
  • Files: ITRD, ATRI
  • Created Date: Aug 6 2007 2:06PM