Premium
Adsorption behavior of surfactant‐polyacrylamide mixtures with kaolin
Author(s) -
Sastry N. V.,
Dave P. N.
Publication year - 1999
Publication title -
journal of surfactants and detergents
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.349
H-Index - 48
eISSN - 1558-9293
pISSN - 1097-3958
DOI - 10.1007/s11743-999-0094-3
Subject(s) - chemistry , dodecylbenzene , pulmonary surfactant , adsorption , polyacrylamide , polymer , aqueous solution , monolayer , sulfonate , chemical engineering , cationic polymerization , bromide , langmuir adsorption model , solvent , sodium dodecylbenzenesulfonate , polyelectrolyte , gibbs isotherm , langmuir , inorganic chemistry , organic chemistry , polymer chemistry , sodium , biochemistry , engineering
The adsorption behavior of three surfactants—hexadecylpyridinium bromide (HPyBr), sodium dodecylbenzene sulfonate (SDBS), and Triton X‐100 (TX‐100)—on kaolin from aqueous solution is monitored as a function of pH. The nature and shape of the adsorption isotherms are typical and highly dependent on the surfactant structure. All three surfactants adsorb on kaolin beyond the limits of monolayer coverage. Isotherms for HPyBr fit the Langmuir equation well. SDBS isotherms are typical of a two‐stage process, and TX‐100 adsorption isotherms are S‐shaped. The pH‐sensitive adsorption of each surfactant and the models used to represent the isotherms are considered together in explaining the mechanism of adsorption in each case. The complex mixture adsorption behavior from polyacrylamide‐surfactant mixtures is also determined in acidic and basic pH media. Three polyacrylamides, catam1, anam1 and nonam1, are chosen to represent cationic, anionic, and nonionic polymers, respectively. Both competitive and synergistic effects are noted in the mixture adsorption depending upon the polymer‐surfactant pair and the mode of introduction of a second component in the presence of another. The results are explained by considering various factors such as changes in the nature of solvent power of the media, interaction between the polymer and surfactant in the bulk solution as well as at the kaolin surface, blocking of surface sites by a preadsorbed component, and the change in the conformation state of polymer chains