130 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS 3.5 2.5 2 1.5 O.5 0 0.1% solids aqueous solution 30 minutes Figure 1. Substantivity: Gel permeation chromatography. and Van der Waals attraction forces with the hair, appear to work together to provide polymer substantivity on hair. The present study was performed on aqueous solutions of the cationic conditioning polymers. The interference from other components (cationic, anionic, or amphoteric surfactants) present in formulated products has not yet been assessed. 120 100 80 60 40 20 0 -20 -40 0 Neutral pH I • I , I , I , I , I 0.5 I 1.5 2 2.5 3 Substantivity (micrograms of polymer/milligrams of hair) Figure 2. Substantivity vs mole % of cationic net charge 3.5

GEL PERMEATION CHROMATOGRAPHY 131 0 3.5 0.5 1 1.5 2 2.5 3 Substantivity (micrograms of polymer/milligrams of hair) Figure 3. Substantivity vs molecular weight. Previous data regarding the substantivity of polyquaternium 7 was determined using C TM tagged polymer (2) on very damaged bleached blond hair at 22øC and an exposure time of 30 minutes. The result obtained using the GPC/RI method under the same set of conditions correlated with the result obtained by tagging the polymer with C•4: GPC Substantivity C TM Substantivity Polymer (pg polymer/mg of hair) (pg polymer/mg of hair) Polyquaternium 7 7.0 7.1 CONCLUSION Gel permeation chromatography proved to be a very effective, quick, and easy method to measure the substantivity of cationic polymers on hair from aqueous solutions. This method is also reproducible within closely defined parameters. Not only was quantifi- cation of cationic polymers possible, but specially synthesized materials were not re- quired. No direct correlation was found between the substantivity of the polymers under the tested conditions and their molecular weight or mole percent of cationic net charge. The latter two factors, plus the ability of the polymer to form hydrogen bonding and Van de Waals attraction forces with the hair, appear to work together to provide polymer substantivity on hair. REFERENCES (1) M. Hamburg, Statistical Analysis for Decision Making, 1983. (2) A. R. Sykes and P. A. Hammes, The use ofmerquat polymers in cosmetics, Drug Cosmet. Ind. (February 1980).