Skip to content
Licensed Unlicensed Requires Authentication Published by De Gruyter May 1, 2013

Pseudo Ternary Diagrams of Pesticide Microemulsion Systems

Pseudo-ternäre Phasendiagramme von Mikroemulsionen mit Pestiziden
A. P. Pratap and D. N. Bhowmick

Abstract

In application of pesticide formulations, use of microemulsion systems offer several advantages over conventional systems such as wettable powders, emulsifiable concentrates (EC's), oil in water emulsions (O/W emulsions), water in oil emulsions (W/O emulsions) and aqueous suspension concentrates. Microemulsion systems are preferred for their long-term thermodynamic stability, low viscosity and ultimate economy. Microemulsion system also enables the usage of the least expensive solvent such as water. Formulation of agrochemical microemulsion is not a straightforward process. However, the pseudo ternary plot is a convenient mean of determining the compositions of microemulsion, macroemulsion and solubilized systems. Identification of specific regions in a pseudo ternary plot makes it possible to arrive at economical composition for microemulsion and solubilized systems. Such compositions gave maximum stability with the optimum usage of surfactants. These microemulsion and solubilized systems when diluted with the inexpensive solvent such as water gave macroemulsion and microemulsion respectively, which were stable over an extended period of time. This paper provides the basis for a simple procedure for the preparation of microemulsion systems employing water, oil, surfactant and cosurfactant.

Kurzfassung

Der Einsatz von Mikroemulsionen bei Pestizidformulierungen bietet verschiedene Vorteile. Im Vergleich zu den konventionellen Systemen wie netzbare Pulver, konzentrierte Emulsionen (EC's), Öl-in-Wasser-Emulsionen (O/W-Emulsionen), Wasser-in-Öl-Emulsionen(W/O-Emulsionen) und konzentrierte wäßrige Suspensionen besitzen Mikroemulsionen thermodynamische Langzeitstabilität, geringe Viskosität und große Wirtschaftlichkeit (Sparsamkeit). In Mikroemulsionen können auch preiswerte Lösemittel wie Wasser eingesetzt werden. Agro-chemische Mikroemulsionen sind nicht einfach herzustellen. Dennoch ist ein pseudo-ternäres Phasendiagramm ein geeignetes Mittel die Zusammensetzung von Mikroemulsion, Makroemulsion und solubilisierten Systemen darzustellen. Mit Hilfe der Identifikation spezifischer Regionen im pseudo-ternären Diagramm ist es möglich, zu Mikroemulsionen und solubilisierten Systemen zu gelangen, die in ihrer Zusammensetzung wirtschaftlich sind und eine maximale Stabilität bei optimalen Tensideinsatz besitzen. Derartige Mikroemulsionen und solubilisierte Systeme liefern bei Verdünnung mit einem preiswerten Lösemittel wie Wasser Makroemulsionen bzw. Mikroemulsionen, die über einen längeren Zeitraum stabil sind. In dieser Arbeit werden die Grundlagen für ein einfaches Vorgehen bei der Herstellung von Mikroemulsionen aus Wasser, Öl, Tensid und Co-Tensid vorgestellt.


Correspondence to Prof. D. N. Bhowmick Division of Oils, Oleochemicals and Surfactants, Institute of Chemical Technology, University of Mumbai, Nathalal Parekh Marg, Matunga, Mumbai – 400 019, India, Tel: +91-22-24145616 Ext. 402, 404, 370, Fax: +91-22-24145614, E-mail:

Prof. D. N. Bhowmick born in 1951 completed his B. Sc. (Tech.) and M. Sc. (Tech.) in Oil Technology from Harcourt Butler Technological Institute (HBTI), Kanpur, India in 1975 and obtained his Ph. D. from Indian Institute of Technology (IIT), Mumbai. He has worked in Godrej Industries (formerly Godrej Soaps), Mumbai, as a Scientist in the R & D section. Presently he is Professor and Head, Division of Oils, Oleochemicals and Surfactants, Institute of Chemical Technology, (formerly UDCT) Mumbai. His research interest includes Surfactants, Novel methods in Oil processing, lubricants and specialty products etc.

Mr. Amit P. Pratap completed his B. Sc. (Tech.) and M. Sc. (Tech.) in Oil Technology in 2001 from Division of Oils, Oleochemicals and Surfactants, Institute of Chemical Technology, Mumbai. At present he is an Academic Associate and working for the doctoral program under the guidance of Prof. D. N. Bhowmick.


References

1. Sonntag, Norman O. V.: In Surfactants in herbicide dispersions in Surfactants in Chemical or Process Engineering, edited by Wasan, D. T., Ginnand, M. E., Shah, D. O., Marcel Dekker Inc., New York, 1988, Surfactant Science Series Vol. 28, p. 238.Search in Google Scholar

2. Lissant, K. J.: Iin Making and breaking emulsions in Emulsions and Emulsion Technology, edited by LissantK. J., Marcel Dekker Inc., New York, 1974, Surfactant Science Series Vol. 6, Part I, p. 7374.Search in Google Scholar

3. Prince, L. M.: In Microemulsions, in Emulsions and Emulsion Technology, edited by LissantK. J., Marcel Dekker Inc., New York, 1974, Surfactant Science Series Vol. 6, Part I, p. 126127.Search in Google Scholar

4. Tadros, T. F.: In Surfactants in Agrochemicals, Surfactant Science Series Vol. 54, Marcel Dekker Inc., New York, 1995, p. 15.Search in Google Scholar

5. Sonntag, Norman O. V.: In Surfactants in herbicide dispersions in Surfactants in Chemical or Process Engineering, edited by Wasan, D. T., Ginnand, M. E., Shah, D. O., Marcel Dekker Inc., New York, 1988, Surfactant Science Series Vol. 28, p. 238239.Search in Google Scholar

6. Gelbert, W. J.: In The New Science of Complex Fluids in J. of Physical Chemistry100 (1996) 1316913189.10.1021/jp9606570Search in Google Scholar

7. Prince, L. M.: In Schulman's microemulsions and formulation in Microemulsions Theory and Practice edited by PrinceL. M., Academic Press Inc., New York1977, p. 3, 40.10.1016/B978-0-12-565750-1.50008-4Search in Google Scholar

Received: 2003-3-4
Published Online: 2013-05-01
Published in Print: 2004-04-01

© 2004, Carl Hanser Publisher, Munich

Downloaded on 1.12.2022 from frontend.live.degruyter.dgbricks.com/document/doi/10.3139/113.100211/html
Scroll Up Arrow