DIRECT ETHOXYLATION OF FATTY ACID GLYCERIL ESTERS FROM PALM OIL AS NON-IONIC SURFACTANTS

Introduction

Surface-active agents (surfactants) are used in almost any household and personal care product as well industrial process, they can acts as a detergent, emulsifier or dispersants in colloidal systems. Directly ethoxylated fatty acid methyl esters are emerging on the markets as surfactants. Taking into account the reduced production cycle of fatty acid methyl esters compred with fatty alcohols, significant cost reduction could be expected.

With the advanced development of oleochemistry, surfactants from palm oil is currently an interesting issue to be investigated. Ethoxylation as one of the polymeric nonionic surfactants are produced in industry by reacting ethylene oxide with an organic molecule containing mobile hydrogen such as fatty alcohols, alkyl phenols, or fatty acids. The general mechanism for ethylene oxide addition to fatty methyl ester has been described, stating that the added molecule is inserted selectively between the carbonyl carbon and methoxy group at the ester bond [3]. Di Serio et al. conducted ethoxylation in the liquid phase, at 150-180ºC and 2-5 atm, in the presence of an alkaline catalyst.

Ethoxylation produces polymeric surfactants which lengthens the hydrophilic part of the surfactant. Polymeric surfactants serve all the same functions as normal surfactants, the main difference being their greater molecular mass and higher order structural conformation. Polymeric surfactants adsorb at surfaces, either of solids to give enhanced colloidal stability, or of liquids to control foaming or emulsion stability. The choice of monomer will normally depend upon the properties required for the polymeric surfactant. Therefore, an oil soluble surfactant which stabilises an aqueous dispersed phase in an oil may be prepared by grafting hydrophobic monomers onto a water soluble substrate. For the reverse system, a water-soluble surfactant which stabilises an oil phase in water can be made by grafting hydrophilic monomers on to a hydrophobic substrate.

      Surfactants are amphiphatic molecules which have a hydrophilic and hydrophobic part. Both parts have strong influence on their properties and ability to sustain stability. In this research, synthesis of polymeric surfactant was performed by direct ethoxylation, reacting ethylene oxide with glyceril eters.The glyceril esters were derivered from palm oil in the prescence of an alkaline catalyst. Analysis will be conducted using Fourier Transform Infrared (FTIR) and Nuclear Magnetic Resonance (NMR).