JOURNAL OF COSMETIC SCIENCE 30 shampoos may give the formulator some fl exibility to balance combing/feel with deposi- tion, possibly enabling use of less polymer or less silicone (an expensive component) in the formulation. C ONCLUSIONS I t has been demonstrated in this preliminary work that a high throughput combinato- rial synthesis and screening approach can be used to identify the compositions of po- tential high-performance synthetic cationic conditioning polymers. A high throughput method for polymer synthesis was used to prepare cationic polymer candidates which were characterized by monomer conversion, % polymer solids, molecular weight and PDI, haze, and viscosity. Shampoo formulations were prepared in a single shampoo base with those polymers that demonstrated the required clarity and high monomer conver- sion in high throughput screens. Hair tresses were treated with these shampoo formulations for subsequent testing of wet combing and wet feel in initial performance screens. Numerous polymers in the tested shampoo formulations enabled substantial reduction in wet combing work, apparently showing greater wet comb performance than a shampoo formulation made with a cellulosic polymer, PQ-67. A shampoo formulation contain- ing polymer P3 was only slightly hazy and exhibited lower wet combing work relative to a PQ-67-based shampoo. A panel study indicated similar performance of PQ-67- and P3-containing shampoo formulations. A shampoo formulation with P3 enabled greater silicone deposition (by 8-fold) than a formulation made with cationic guar. P3 is a wholly vinyl monomer-based cationic conditioning polymer with hair conditioning effi ciency equal to or greater than that of PQ-67 in the shampoo formulation studied. Further studies will be needed to elucidate the specifi c polymer microstructural basis of the observed conditioning effi cacy in this one formulation, as well as the range of formulations and treatments in which it is effective. A CKNOWLEDGMENTS W e are grateful to the Dow Chemical Company, to FreeSlate (now Unchained Labs), and to Damian Hajduk, Robert Mussell, Greg Cardoen, and Curtis Schwartz for their support Figure 4. Silicone deposition onto hair from shampoo formulations containing different conditioning poly- mers. Dark bars are error bars.

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