JOURNAL OF COSMETIC SCIENCE 426 of bound micelles. Thus, different coacervation and/or precipitation can be obtained from a surfactant/polymer system by changes in ionic strength or salt content. The data from this study show that the salt screening effect may infl uence the coacervation behavior and therefore the cationic and silicone deposition of the lower cationic charge density poly- mers such as cationic guar CG0.98 and PQ-10 1.03, compared to the cationic cassia polymers with higher cationic charge density. CONCLUSIONS The results show that different factors infl uence the conditioning performance of different cationic polymers. The formulation composition has a strong infl uence on the silicone and cationic polymer deposition that are primary determinants of the conditioning performance. Three parameters are highlighted to be of importance in determining silicone and cationic polymer deposition: ionic strength, average surfactant charge (micelle charge), and the total amount of surfactant. Silicone and cationic polymer deposition re- sults can be predicted to a high confi dence level using models that incorporate these three factors. There appears to be several mechanisms that are of importance in determining silicone and cationic deposition and, therefore, conditioning performance. Which of these factors is operative may depend on the cationic polymer molecular weight, cationic charge density, polymer chain fl exibility, and solubility. A summary of these factors for silicone deposition and cationic polymer deposition is in Tables III and IV, respectively. Silicone and cationic deposition data indicate that increasing the interaction between the cationic polymer and surfactant by either using a more highly charged cationic polymer, decreas- ing the aspect ratio of the surfactant structuring (lower surfactant amount), or decreasing the ionic strength (less ionic interaction shielding) may contribute to better deposition. Table III Summary of the Factors Infl uencing Silicone Deposition for Each Cationic Polymer (Increasing Factors) Silicone deposition Cationic cassia Cationic guar Cationic hydroxyethyl cellulose Surfactant amount ↓a ↓ Micelle charge ↑ ↑ ↓ Ionic strength ↓ Cationic charge a Signifi cant interaction with micelle charge (Figure 5). Table IV Summary of the Factors Infl uencing Polymer Deposition for Each Cationic Polymer (Increasing Factors) Cationic deposition Cationic cassia Cationic guar Cationic hydroxyethyl cellulose Surfactant amount ↓a ↓ ↓ Micelle charge ↑ ↑b Ionic strength ↑ ↓ Cationic charge ↑ a Signifi cant interactions with micelle charge and cationic charge (Figure 10). b Signifi cant interaction with ionic strength (Figure 12).

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