A LOOK AT SOME TYPICAL HAIR CARE SURFACTANTS.

ALKYL (LAURYL) SULFATES are one of the most widely used surfactants in shampoos or bubble baths. Sodium and ethoxylated sodium salts are especially popular with formulators. Ammonium lauryl sulfate is also used, but only in acid shampoo systems. A different detergent that is utilized much less frequently is alpha olefin (AOS). One manufacturer of AOS and alpha olefin sulfonate, its base material, is Chevron Phillips (formerly Chevron Chemical), Houston, TX. The company provided this information. Alpha olefins can synthesize any derivative requiring an even-numbered, straight carbon chain. Alpha olefin, RCH=[CH.sub.2], is available in various carbon lengths from [C.sub.4] (1-butene) to [C.sub.18] (1-octadecene). The double bond at the end of the chain is very reactive. If ethylene is added, a copolymer is formed as follows:

RCH=[CH.sub.2] + [CH.sub.2]=[CH.sub.2]
 ([CH.sub.2][CH.sub.2]CH[CH.sub.2][CH.sub.2][CH.sub.2]-)n

                      R

1-butene, 1-hexene and 1-decene are used as comonomers with ethylene to produce high-density polyethylene resins.

It can also be homopolymerized with the same catalysts used above to form 1-polybutene, as in the following:

RCH=[CH.sub.2]   (-CH[CH.sub.2]CH[CH.sub.2]CH[CH.sub.2]-)

                   R           R           R

Polybutene behaves similarly to a cross-linked plastic and has excellent long-term mechanical properties.

Alpha olefins can be converted into alkyl dimethyl amines which, if oxidized by hydrogen peroxide, form amine oxides. These ingredients boost foam in shampoos. Reacting the amines with sodium chloroacetate produces betaines, another surfactant found in shampoos.

To make AOS, alpha olefins are sulfonated to produce a mixture of alkene sulfonic acids and sultones. This mixture is then neutralized with NaOH and hydrolyzed to convert the sultones to alkene and hydroxy sulfonates. This results in an aqueous solution of AOS. Blends of [C.sub.14-16] AOS are often used as foaming ingredients. According to Chevron, a [C.sub.12-16] blend of alpha olefins has an oral LDb0 rating of [is greater than] 10g/kg, a primary skin irritation index (Draize) of 0.4 and a 24-hour eye irritation score (Draize) of 1.0.

AOS surfactants have good detergency, are highly compatible with hard water, have good wetting and foaming properties and biodegrade rapidly. Prices are equivalent, so I investigated why they are not used more often in personal care products. When AOS was created about 20 years ago, it was difficult to maintain batch-to-batch consistency. In addition, there were some problems with irritation. Apparently, memories of these initial issues still linger within the industry. It is a little more difficult to increase viscosity with AOS than with lauryl sulfates. Betaines will increase shampoo viscosity with AOS, but salt and lauramide DEA do not work as well as they do with lauryl sulfates. A shampoo formula, which combines AOS, betaine and an amine oxide, was developed by Scher Chemicals, Clifton, NJ.

Gel Shampoo

Ingredient                     %Wt.

Phase A
Sodium lauryl sulfate (30%)      20
Alpha olefin sulfonate (40%)     10
Disodium monooleamidoeth         10
 MEA sulfonate
Cocamidopropyl betaine           10
Cocamidopropylamine oxide         3

Phase B
Isostearamidopropyl ethyl         1
 dimonium ethosulfate
Water                            42

Phase C
Herbal extracts                   4
Preservative                   q.s.

Procedure:

Mix phase A in order given. Heat to 60 [degrees] C. Add B in separate container. Stir constantly and keep temperature at 60 [degrees] C. Cool and add C.

The following formula for liquid bub ble bath was created by R.I.T.A., Woodstock, IL. It uses AOS to create copious foam:

Liquid Bubble Bath

Ingredient                                          %Wt.

Water                                                 48
Sodium [C.sub.14-16] olefin sulfonate                 40
Sodium isostearoyl lactylate                           3
Lauramide DEA                                          5
PEG-75 lanolin                                         4
Fragrance, color, preservative                      q.s.
Lactic acid                             q.s. to pH 6.5-8

Procedure: Add perfume to Lauramide DEA. Add sodium isostearoyl lactylate. Mix until uniform. Combine water and solfonate. Add premixed lauramide to water-sulfonate mixture and stir until uniform. Add PEG-75 lanolin and mix. Adjust pH with lactic acid.

HARVEY FISHMAN WAS A CONSULTING FIRM AT 34 CHICASAW DRIVE, OAKLAND, NJ 07436, ([e-mail]) SPEZIALIZING AT COSMETIC FORMULATIONS AND NEW PRODUCT IDEAS, OFFERING TESTED FINISHED PRODUCTS. HE HAS MORE THAN 30 YEARS OF EXPERIENCE AND HAS BEEN DIRECTOR OF RESEARCH AT BONAT, NESTLE LEMUR AND TURNER HALL. HE WELCOMES DESCRIPTIVE LITERATURE FROM SUPPLIERS AND BENCH CHEMIST AND OTHERS IN THE FIELD.