ATLAS CHEMICALS DIVISION ATLAS POWDER C O M P A N Y , W I L M I N G T O N 9 9 , DELAWARE
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ATLAS POWDER C O M P A N Y , C A N A D A . I T D „ BRANTFORD. O N T A R I O , C A N A D A
Structure of Typical Surfactants DESCRIPTION
A typical . the chracteristic
An alkyl chloride. These A t y p i c a l S P A N ® o r ARLACEL.® sorbîtan f a t t y a d d ester (mafor component). Predominantly l i p o -
HOCH
tending t o emulsions.
/ CH2
water-in-oil
H0(CH2CHa0)n HO(CH2CH20)nCH
CH-CHCH200 0
H0(CH2CH20)nCH
CH2
H0(CH2CH20)n0i
A typical T W E E N ® p o l y o x y e f h y l ene sorbîtan f a t t y acid ester (major component). Predominantly hydrophilic in action a n d t h e r e f o r e tending t o form oil-in-water emulsions.
A typical MYRJ® polyoxy ethylene f a t t y acid ester (major c o m ponent). Predominantly h y d r o philic in action a n d t h e r e f o r e tending to form oil-in-water emulsions.
A typical BRU® polyoxyethylene f a t t y ether (major component). Since it contains no ester Knkopes, it is stable t o many alkalies· a n d acids b e y o n d the usual p H r a i t g e which o r d i n a r y emulsifiers a a n withstand. Predominantly hydrx>philic in action and t h e r e f o r e tending to f o r m oiI-in-wa*er emulsions.
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INVESTIGATE N O N - I O N I C S FIRST W H E N YOU NEED SURFACTANTS When y o u need one or more surfactants, i t will pay you to investigate the inherent advantages of non-ionics—a field in which Atlas has specialized for over 15 years. Here are some of the main reasons why. No hard -water problems. Non-ionic surfactants aren't bothered by water hardness because they do not react with the ions that make water hard. For example, almost everyone is familiar with the way non-ionic detergents clean dishes or clothes in hard water without leaving a scummy deposit, and this "inertness" toward ions also means water hardness problems can be disregarded in many types of formulating—for example, an insecticide concentrate made with a non-ionic emulsifier* will disperse readily in the hardest water a farmer might use. Fewer problems of incompatibility. Because non-ionics get along chemically with almost any other kind of chemical ingredient, including ionic surfactants and other ingredients that ionize, they allow yoix virtually complete freedom of choice i n your other ingredients for cosmetics, pharmaceuticals» cleaning compounds and other emulsion products. Better control over pH problems· Non-ionics are essentially neutral. They 're inherently mild and non-irritating. They are stable in the presence of electrolytes, and you can use thern in emulsions containing mild acids, alkalies and salts, obtaining stable emulsions. Other unique advantages. Non-ionics are especially valuable in formulating cosmetic creams, because creams made with non-ionic emulsifiers do not "crust" on exposure a s do soap-emulsified creams.
detergent, and whether it will make oil-in-water emulsions or water-in~oil. The lipophilic portion of most surfactants is a long hydrocarbon chain, soluble in oil but not m water. The major difference between various kinds of surfactants lies mainly in the hydrophilic portion, as shown in the chart. Anionic surfactants. Soaps and alkyl aryl sulfonates are typical of this class. Anionics get their attraction for water from the charged end of the anion (—) and the positive ion (usually sodium). Cationîc surfactants. Amine salts or quaternaries are typical cationics. χ at χ i s
νιαοο
vfi.
o u t KUVVCUIVO
^^»*Λ»
m %«*
water-attraction power from the charged end of the cation (-f ) and the negative ion (often chloride or bromide). Non-ionic surfactants do not dis s o c i a t e in water. We vary the hydrophilic characteristics of Atlas materials, for example, by addi tion of polyoxyethylene chains. The longer the chain, the greater is the attraction of the surfactant for water, arid the more pronounced is its tend ency to form oil-in-water emulsions.
Manufacturers of cleaning compounds prefer nonionics for automatic dishwashers or laundering machines because they help control excessive foaming.
Difference B e t w e e n Surfactants The chart on the opposite page shows some of the basic chemical differences between various kinds of surfactants. . Notice that every kind of surfactant molecule has a dual nature. That is, one portion is hydrophilic or waterloving and another portion is lipophilic or oil-loving. Thus, a surfactant acts as a link between oil and water. T h e relative strength of the two portions determines how the surfactant will act—whether it will be a good
Look into Atlas n o n - i o n i c s next time you're searching for surfactants. W e make a lot of different types, and we can help you use them most effec tively. If you'd like more tech nical data, send for the Atlas booklet, "General Character istics of Atlas Surfactants," which shows properties of 95 kinds we make.
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