Murali Rajaraman
@nccas.edu.in
Associate Professor, Department of Chemistry
Nanjil Catholic College of Arts and Science
RESEARCH, TEACHING, or OTHER INTERESTS
Chemistry, Multidisciplinary, Environmental Chemistry, Geochemistry and Petrology
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
R. Murali, C. N. Murthy, and R. A. Sengupta
Springer Science and Business Media LLC
Rakesh Sharma, Rajaraman Murali, and Chivukula N. Murthy
Walter de Gruyter GmbH
Abstract Aqueous solutions of commercially available Pluronic®R i. e. triblock copolymer composed of polypropylene oxide(PPO)-polyethylene oxide(PEO)-polypropylene oxide(PPO), (code named 25R4, BASF) in the presence of surfactant additives viz. hydrotropes (NaTS, NaXS), anionics (SDS, SDBS) and cationics (DTAB, CTAB) were investigated by cloud point(CP), surface tension and conductance techniques. All the techniques clearly indicated that Pluronic®25R4 interacts strongly with anionic surfactants but weakly with cationic surfactants. Surfactant additives used here, produced a marked increase in the CP of the copolymer. Elevation in CP is attributed to the solubility of PPO block of the copolymer and formation of Pluronic-surfactant complex. The effect of NaCl salt on the CP of Pluronic®25R4 at added SDS and CTAB was also studied and it was decreased due to the screening effect. At the presence of 25R4 in its non-associated form, the surface tension and conductance data is discussed with binding process and indicated strong interaction of Pluronic®25R4 with SDS, showing two break points (P1 and P2) in the plot and very weak interaction with CTAB observing single break point.
C. N. Murthy, Rashmika R. Patel, R. Murali, and A. K. Rakshit
American Chemical Society (ACS)
[60]Fullerene has zero solubility in water and very low solubility in many organic solvents. It was found that it forms reverse micelles in organic solvents in the presence of nonionic surfactants. Reverse micellization studies of fullerene solutions in the presence of a nonionic surfactant (Span60) were carried out, and the thermodynamic quantities of the reverse micellization process derived from experimental results indicate that the process is spontaneous. The solution behavior of the [60]fullerene was understood from its ability to form microemulsions from its toluene solution and water using different nonionic surfactants. Light scattering studies showed that the dimensions of these microemulsions reach a maximum of 170 nm. Phase behavior at different temperatures indicates the very high surface active nature of [60]fullerene.