الفهرس 
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Abstract
Surfactants are a diverse group of chemicals that are designed to have cleaning or
solubilisation properties. They generally consists of a polar head group (either charged or
uncharged), which is well solvated in water, and a nonpolar hydrocarbon tail, which is not
easily dissolved in water. Hence, surfactants combine hydrophobic and hydrophilic
properties in one molecule. Synthetic surfactants are economically important chemicals.
They are widely used in household cleaning detergents, personal care products, textiles,
paints, polymers, pesticide formulations, pharmaceuticals, mining, oil recovery and pulp
and paper industries. The world production of synthetic surfactants amounts to 7.2 million
tons annually (1). Surfactants are used together with polymers in a wide range of
applications, formulations usually contain a combination of a low molecular weight
surfactant and a polymer which mayor may not be highly surface active. Together, the
surfactant and polymer provide the stability, archeology, etc., needed for specific
application. The solution behavior of each component is important, but the performance of
the formulated product depends to a large extent on the interplay between the surfactant
and polymer. Hence knowledge about physicochemical properties of both surfactants and
polymers and not least about surfactant-polymer interactions, is essential in order to make
formulation work more of a science than an art. Until recent years soap and water the only
cleaning agents available. Soap served society well for many years, until shortage in
animal and vegetable fats and oils, the basic ingredients necessary to make soap, during the
World Wars I and Il, prompted research into potential alternatives. The studies led to the
commercial discovery of surfactants which could be made synthetically from
petrochemicals, which readily available. This development proved to be a further stroke of
luck for the cleaning industry and society. Unlike the traditional soap, the surfactants were
more resistant to hard water and therefore improve the efficiency of the cleaning process.
Surfactants consisted mainly of three types: anionic, nonionic, and cationic (Table
1). Linear alkylbenzene sulphonates (LAS), alkyl ethoxy sulphates (AES), alkyl sulphates
(AS), alkylphenol ethoxylates (APE), alkyl ethoxylates (AE), and quaternary ammonium
compounds (QAC) are the commonly used commercial surfactants. Especially, LAS, APE,
and QAC are the most extensively studied surfactants. Linear alkylbenzene sulphonates
(LAS) was first commercialized in the early 1960s as a replacement for the poorly
biodegradable DDBS (Dodecyl benzene sulphonate - Branched alkylbenzene sulphonate),
which caused persistent foam in sewage treatment plants, streams and rivers. Linear
alkylbenzene sulphonates (LAS) may be considered as the first ”green” cleaning agent,
because it was the first surfactant introduced to solve an environmental problem.
Such replacement was the result of a vast research effort followed by investments
to provide the world surfactant and detergent industry with one of the most cost-effective
and environmentally safe surfactants. These investments activities have continued during
the last 40 years and have yielded continuous improvements in quality and safety as well
as new developments in both LAB (Linear alkylbenzene, the raw material for LAS) and
sulphonation processes. In parallel with the technological developments, substantial
research is also continuing, and still continuous today, in order to provide all the
stakeholders with the most detailed and comprehensive knowledge about the
environmental and human safety of LAS. Today LAS is probably the most researched
chemical available. LAS, after soap, the most widely used surfactants in all detergents and
cleaning products. It is the surfactant of choice by detergent manufactures, not only.