1st Edition

Surfactants in Agrochemicals

By Tharwat F. Tadros Copyright 1995
280 Pages
by CRC Press

284 Pages
by Routledge

This work highlights the physical chemistry of surfactant solutions, detailing a fundamental method of selecting surfactants for agrochemical formulations and delineating how surfactants enhance the biological efficacy of agrochemicals. The unique properties of surfactants that have a major influence on the performance of an agrochemical are summarized.;The book is intended for physical, surface... Read more

Preface

1 General Introduction

2 Physical Chemistry of Surfactant Solutions

General Classification of Surface Active Agents

Properties of Solutions of Surface Active Agents

Thermodynamics of Micellization

Kinetic Aspects

Equilibrium Aspects: Thermodynamic Treatment of Micellization

Enthalpy and Entropy of Micellization

Driving Force for Micelle Formation

3 Adsorption of Surfactants and Polymers at the Air/Liquid, Liquid/Liquid, and Solid/Liquid Interfaces

Adsorption of Surfactants at the Air/Liquid and Liquid/Liquid Interface

The Gibbs Adsorption Isotherm

Equation of State Approach

Adsorption of Surfactants and Polymers at the Solid/Liquid Interface

Surfactant Adsorption at the Solid/Liquid Interface

Polymer Adsorption

4 Emulsifiable Concentrates

General Guideline for Formulation of Emulsifiable Concentrates

Spontaneity of Emulsification

Fundamental Investigations on a Model Emulsifiable Concentrate

5 Emulsions

Introduction

Formation of Emulsifiers

Selection of Emulsifiers

The Hydrophilic—Lipophilic (HLB) Concept

The Phase Inversion Temperature (PIT) Concept

The Cohesive Energy Ratio Concept

Emulsion Stability

Creaming and Sedimentation

Flocculation of Emulsions

Ostwald Ripening

Emulsion Coalescence

Phase Inversion

Characterization of Emulsions and Assessment of Their Long-Term Physical Stability

Interfacial Properties

Interfacial Rheology

6 Suspension Concentrates

Introduction

Preparation of Suspension Concentrates and the Role of Surfactants

Wetting of the Agrochemical Powder

Dispersion and Milling

Control of the Physical Stability of Suspension Concentrates

Stability Against Aggregation

Ostwald Ripening (Crystal Growth)

Stability Against Claying or Caking

Assessment of the Long-Term Physical Stability of Suspension Concentrates

Double-Layer Investigation

Surfactant and Polymer Adsorption

Assessment of the State of the Dispersion

Rheological Measurements

7 Microemulsions

Introduction

Basic Principles of Microemulsion Formation and Thermodynamic Stability

Factors Determining w/o vs. o/w Microemulsion Formation

Selection of Surfactants for Microemulsion Formation

Characterization of Microemulsions

Conductivity Measurements

Light Scattering Measurements

Role of Microemulsions in Enhancement of Biological Efficacy

8 Role of Surfactants in the Transfer and Performance of Agrochemicals

Introduction

Interactions at the Solution Interface and Their Effect on Droplet Formation

Impaction and Adhesion

Droplet Sliding and Spray Retention

Wetting and Spreading

Evaporation of Spray Drops and Deposit Formation

Solubilization and its Effect on Transport

References

Index

Biography

Tadros, TharwatF.