Liquid Anti-Strip Agents

Liquid Anti-Strip Agents

Moisture causes many common pavement distresses such as potholes, raveling, and rutting. Moisture related damage in asphalt concrete occurs when water removes, or “strips”, the asphalt binder from aggregate surfaces. Scientists and engineers developed anti-strip technologies in response to this serious and expensive problem that greatly decreases pavement ride quality and the expected life span of our roadways.

Liquid Anti-strip agents are liquid chemical additives added to asphalt mix to increase the occurrence and strength of asphalt to aggregate adhesion, which mitigates stripping and the deterioration of the asphalt. Common liquid anti-strip additives based on amine chemistry include:

  • Ethylene amines
  • Polyamines
  • Fatty (tallow) amines
  • Amidoamines

Dytek® BHMT is among the best amine liquid anti-strip additives in prolonging the service life of asphalt

Additives Description
ControlNo LAS Additive
PEGPolyethylene Glycol
HMDHexamtheylenediamine
TETA-OATETA - Oleyl Amide
HMD-EOHMD - Ethylene Oxide adduct
TEATriethanolamine
TETATriethylenetetramine
TETA-DATETA - Dioleyl Amide
Dytek® BHMTBis(hexymethylene)triamine
TETA-EOTETA - Ethylene Oxide adduct

Measurements used to quantitatively describe the moisture damage on changes to adhesion and cohesion in an asphalt mix

TSRTensile Strength RatioDecrease in TSR => loss of cohesion │ softening by water
MRResilient modulusHigh MR => increase in stiffness; may lead to poor fatigue life
Nw/NDRatio of wet life to dry lifea measure of the effectiveness of chemical in improving the service life of asphalt │ higher the value, better the performance
(TSR)2/MRRToughness ratioAlternative to NW/ND │ larger value preferred