Brookfield DV3T Rheometer User Manual
Page 84
Brookfield Engineering Labs., Inc.
Page 84
Manual No. M13-2100
An Example of the Power Law Model at Work
Formulators at a personal care company
would like to use a substitute ingredient to
decrease cost. They use the Power Law model
to evaluate the effect the new ingredient
will have on the behavior of their shampoo.
They need to know how it will behave during
processing and how it will behave when it is
being used be the consumer
With the new ingredient the shampoo has a flow index (
n) of 0.08. This indicates that the
shampoo is shear-thinning enough to flow properly during processing and that it will flow
properly for the end-user. The consistency index,
k, indicates how the shampoo behaves
when it experiences low shear rates. The power law values show that the shampoo becomes
quite thin at process shear rates and therefore it can be easily pumped into filling equipment,
hold tanks, etc. The consistency index of 91,071 cP shows that the shampoo is very viscous
at low shear rates, and as a result, it will appear to customers to be “rich and creamy” while
still being easy to apply.
Shampoo
Flow Index (
n) = 0.08
Consistency Index (
k) = 91071 cP