Using Polymer Modified Asphalt Emulsions in Surface Treatments A ...

the materials handling and placement practicalities for modified AC-10 and A-30 asphalt
binders.
8000
Viscosity (cP)
6000
4000
2000
AC-30 Base
AC-10 Base
0
0 2 4 6 8 10
SBS Weight Concentration (%)
Figure 17: Viscosity as a Function of SBS Concentration (12)
Serfass et al (1992) report that adequate SBS concentrations are required to ensure
proper formation of a continuous polymer network, and that it is this network which
imparts the most desirable viscoelastic properties to modified asphalt binders. Within
this context, the authors note that “adequate” is highly dependent upon asphalt
compatibility, but is generally within the range of 3% to 5% by weight of residual asphalt
(18).
2.3.3 Storage and Handling Considerations
Proper storage conditions represent one of the most common problems associated with
the use of PME. The mixing processes used are complex and often proprietary, and as
such, modified binders are generally acquired in an already-blended form from the
supplier. Once batched, the mixture must be placed in a special holding tank that can
be continuously agitated to prevent the phase separation problems which were noted
previously and described in some detail. Temperatures during storage must also be
strictly controlled to prevent setting, premature breaking (emulsions), and/or thermal
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