Shampoo and Conditioner Science 82 These micelles also form branched as well as linear structures, and above a certain concentration (the critical overlap concentration, C*) they entangle just like polymer molecules17 and display viscoelastic rheology.18-20 This behavior is depicted in Figure 7 as it was explained by Candau in 1993.21 Increase in salt concentration causes spherical or elliptical micelles to transition into rods, then to worms then to branched worms. As the surfactant concentration increases, the micelles form entangled networks. Consumers desire thicker Figure 5. Surfactant molecules with a packing factor of ½ pack naturally into cylinders. Figure 6. Surfactant molecules with a packing factor of 1 pack naturally into bilayer planes.