2004 Volume 53 Issue 10 Pages 1119-1123
Cationic polymers in hair shampoo form a complex with an anionic surfactant, and adhere to the hair when the shampoo is rinsed. This complex plays an important role in the feeling of the rinse for user, and in the conditioning provided by the shampoo. Therefore, the amount and molecular weight information of the cationic polymer is important for examining both the performance and quality control. Nevertheless, no accurate method has yet been established for analyzing the cationic polymers used for hair shampoo. We used SEC-MALLS-RI (size-exclusion chromatography with a multiangle laser light-scattering detector and refractive index detector) to examine the cationic cellulose [cellulose,2-hydroxyethyl 2-{2-hydroxy-3(trimethylammonio)propoxy}ethyl 2-hydroxy-3-(trimethylammonio)propyl ether,chloride] (CC) used for hair shampoo. In this analysis, we used a column in which the stationary phases were based on vinyl polymer and a 0.3 M NaClO4 solution. The chromatogram was clear and precise, and we verified that the CC was separated by the size of MALLS and RI(plot of molecular weight vs. retention time). There was no adsorption between the CC and the column stationary phases, and the calibration curves showed good agreement with each other. It was determined that any grade of CC could be used as a standard. We conclude that the present technique is an accurate method of measuring the amount of CC and determining its absolute molecular weight used for hair shampoo.
