Polyalkylene glycol ethers
Polyalkylene glycol ethers , and fatty alcohol polyglycol ethers , fatty alcohol ethoxylates (FAEO), ( trade name u. A. Brij ® , Genapol ® , Lutensol ® ), are a series of nonionic surfactants . The lipophilic part of these surfactants consists of fatty alcohols , the hydrophilic part forms short-chain polyethylene glycols (polyoxyethylene). The alcohols derived from lauric , palmitic , stearic or oleic acid are used as fatty alcohols.
Manufacturing
Polyalkylene glycol ethers are produced from fatty alcohols and ethylene oxide via an ethoxylation reaction with a suitable catalyst and a temperature of 150 to 180 ° C. and a pressure of 2 to 5 bar.
![{\ displaystyle \ mathrm {R {-} OH + n \ C_ {2} H_ {4} O \ longrightarrow R {-} O {-} [CH_ {2} {-} CH_ {2} {-} O] _ {n} {-} H}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/6125cb438d194057ccbbad3878528c18fa28a50e)
An analogous reaction takes place if propylene oxide is used instead of ethylene oxide .
properties
These surfactants are resistant to acids and bases , even beyond the pH value in which surfactants of the ester type do not exist. Consequently, they are suitable for emulsifying fats and oils in very acidic or very alkaline environments. Depending on their HLB values , the surfactants can either form oil-in-water (O / W) or water-in-oil (W / O) emulsions or improve the wettability .
use
Polyalkylene glycol ethers as surfactants are widely used in personal care products, textile processing, crop protection products, paints and coatings, adhesives and other industrial applications. Brij 35 is used as a detergent in biochemistry . Since there proteins as opposed to SDS not denatured, it is used to membrane proteins in their native conformation of membrane extract.
Fatty alcohol ether sulfates (FAES), which are important as anionic surfactants, are obtained by reacting polyalkylene glycol ether with sulfur trioxide or chlorosulfonic acid .
Commercially available polyalkylene glycol ethers
The general formula of the polyalkylene glycol ethers is 
.
In the formula, m + 1 denotes the number of carbon atoms in the alkyl chain. n indicates the average number of ethylene oxide units per mole; it is given in brackets in the substance name.
| Some commercially available fatty alcohol ethoxylates | |||
|---|---|---|---|
| Chemical name | other names | HLB value | Trade names, examples |
| Polyoxyethylene ether of lauryl alcohol (12 carbon atoms), CAS number 9002-92-0, macrogol lauryl ether | |||
| Polyoxyethylene (4) lauryl ether | Laureth-4 ( INCI ) | 9.7 | Brij 30 |
| Polyoxyethylene (9) lauryl ether | Laureth-9 (INCI) | Thesit | |
| Polyoxyethylene (23) lauryl ether | Laureth-23 (INCI) | 16.9 | Brij 35 |
| Polyoxyethylene ether of cetyl alcohol (16 carbon atoms), CAS number 9004-95-9 | |||
| Polyoxyethylene (2) cetyl ether | Ceteth-2 ( INCI ) | 5.3 | Brij 52 |
| Polyoxyethylene (10) cetyl ether | Ceteth-10 (INCI) | 12.9 | Brij 56 |
| Polyoxyethylene (20) cetyl ether | Ceteth-20 (INCI) Cetomacrogol 1000 ( INN ) |
15.7 | Brij 58 |
| Polyoxyethylene ether of cetyl stearyl alcohol (16/18 carbon atoms), CAS number 68439-49-6, macrogol cetyl stearyl ether | |||
| Polyoxyethylene (6) cetyl stearyl ether | Ceteareth-6 (INCI) | 10-12 | Cremophor A6 |
| Polyoxyethylene (20) cetyl stearyl ether | Ceteareth-20 (INCI) | ||
| Polyoxyethylene (25) cetyl stearyl ether | Ceteareth-25 (INCI) | 15-17 | Cremophor A25, Marlipal 1618/25 |
| Polyoxyethylene ether of stearyl alcohol (18 carbon atoms), CAS number 9005-00-9, macrogol stearyl ether | |||
| Polyoxyethylene (2) stearyl ether | Steareth-2 ( INCI ) | 4.9 | Brij 72 |
| Polyoxyethylene (10) stearyl ether | Steareth-10 (INCI) | 12.4 | Brij 76 |
| Polyoxyethylene (20) stearyl ether | Steareth-20 (INCI) | 15.3 | Brij 78 |
| Polyoxyethylene ether of oleyl alcohol (18 carbon atoms), CAS number 9004-98-2, macrogololeyl ether | |||
| Polyoxyethylene (2) oleyl ether | Oleth-2 ( INCI ) | 4.9 | Brij 92 |
| Polyoxyethylene (10) oleyl ether | Oleth-10 (INCI) | 12.4 | Brij 96, Brij 97 |
| Polyoxyethylene (20) oleyl ether | Oleth-20 (INCI) | 15.3 | Brij 98 |
| Other polyalkylene glycol ethers | |||
| Polyoxyethylene (10) monodecyl ether ( CAS number 26183-52-8) | Deceth-10 (INCI) | ||
| Polyoxyethylene (10) tridecyl ether ( CAS number 24938-91-8) | Trideceth-10 (INCI) | ||
Individual evidence
- ↑ a b Bernd Fabry: Surfactants, properties, raw materials, production, applications . In: Chemistry in Our Time . tape 25 , no. 4 , 1991, pp. 214–222 , doi : 10.1002 / ciuz.19910250407 .
- ↑ Calbiochem Booklet: A Guide to the Properties and Uses of Detergents (PDF; 597 kB).