Nonionic alkylphenol ethoxylates

Both octylphenol and nonylphenol are found in the wider environment as a result of the biodegradation of the alkylphenolic polyethoxylates (APEOs) and are themselves recalcitrant breakdown products. The nonionic alkylphenol ethoxylated surfactants, namely... 

Figure 9.1. Examples of cationic (alkyl pyridinium), anionic (sodium oleate), and nonionic (alkylphenol ethoxylate) surfactants.

In the 1990s, the thmst of surfactant flooding work has been to develop surfactants which provide low interfacial tensions in saline media, particularly seawater require less cosurfactant are effective at low concentrations and exhibit lower adsorption on rock. Nonionic surfactants such as alcohol ethoxylates, alkylphenol ethoxylates (215) and propoxylates (216), and alcohol propoxylates (216) have been evaluated for this appHcation. More recently, anionic surfactants have been used (216—230). 

Alkylphenol ethoxylates (APEs) are nonionic surfactants that are used in the manufacturing of plastics, agricultural chemicals, cosmetics, herbicides, and industrial detergent formulations. Alkylphenols such as nonylphenol (NP) are the products of... 

Nonionic Polyoxyethylenated alkyl-phenols, alkylphenol ethoxylates Emulsifying agents Generally water-soluble Good chemical stability... 

The environmental compatibility of silicone softeners is generally favourable [495,496]. The discussion here concerns only the silicone component of the formulation and not the supporting emulsifying system. For the most part this is nonionic, preferably based on linear ethoxylated fatty alcohols, although alkylphenol ethoxylates are still used in some countries [496]. The salient points regarding the environmental influence of silicones can be summarised as follows ... 

Nonionic surfactants contain (Fig. 23) no ionic functionalities, as their name implies, and include ethylene oxide adducts (EOA) of alkylphenols and fatty alcohols. Production of detergent chain-length fatty alcohols from both natural and petrochemical precursors has now increased with the usage of alkylphenol ethoxylates (APEO) for some applications. This is environmentally less acceptable because of the slower rate of biodegradation and concern regarding the toxicity of phenolic residues [342]. 

This paper will review the biodegradation of nonionic surfactants. The major focus will be on alcohol ethoxylates and alkylphenol ethoxylates—the two largest volume nonionics. In this paper the effect of hydrophobe structure will be discussed, since hydrophobe structure is considered more critical than that of the hydrophile in biodegradability of the largest volume nonionics. The influence of the hydrophobe on the biodegradation pathway will be examined with an emphasis on the use of radiolabeled nonionics. 

A mixture of nonionic surfactants, consisting of a capped alkylphenol ethoxylate or an ethoxylated higher aliphatic alcohol... 

SDS was an exception. Among the traditional surfactant work-horses, including anionics (such as alkylbenzene sulfonates and alkyl sulfates), nonionics (such as alcohol ethoxylates and alkylphenol ethoxylates), and cationics (such as alkyl quats and dialkyl quats), only alkyl sulfates are not chemically stable under normal conditions. 

Important classes of nonionic surfactants are aliphatic poly-ethoxylate alcohols (AEO), and octyl or nonyl phenol polyethoxylates (OPEO and NPEO). The alkylphenol ethoxylates (APEO) attracted special attention due to their supposedly endocrine disrupting properties (Ch. 8.3). LC-MS analysis may also involve nonylphenolethoxycarboxylates (NPEC), biodegradation products of NPEO, and halogenated analogues, generated in chlorine disinfection treatments in drinking water production plants. 

A third class of industrial chemical biocides consists of agents with the ability to inhibit biological film formation, also called surfactants . The term surfactant originates from the phrase surface active agent. Surfactants fall into four broad categories anionic (e.g., soaps, alkyl benzenesulfonates, alkyl sulfonates, alkyl phosphates), cationic (e.g., quaternary ammonium salts), nonionic (e.g., alkyl polyglycosides, alcohol ethoxylates, alkylphenol ethoxylates), and zwitterionic. 

Anon. (1991) Environmental and Human Safety of Major Surfactants. Volume 1 Anionic Surfactants. Part 1. Linear Alkylbenzene Sulfonates. Part 2. Alcohol Ethyl Sulfates. Part 3. Alkyl Sulfates. Part 4. Alpha Olgin Sulfonates. Volume 2 Nonionic Surfactants, Alcohol Ethoxylates and Alkylphenol Ethoxylates. Government Reports Announcements Index (GRA I). 

On a truly commercial scale, the age of liquid detergents can be said to have begun in the late 1940s when the first liquid detergent for manual dishwashing was introduced. This liquid consisted essentially of a nonionic surfactant, alkylphenol ethoxylate. It produced only a moderate amount of foam when in use. 

Nonionic Poly(oxyethylene) alcohol Alkylphenol ethoxylate... 

Nonionic surfactants like alkylphenol ethoxylates (APEO) and their biodegradation products alkylphenol diethoxylate (AP2EO), alkylphenol monoethoxylate (APIEO), and AP are isolated from aqueous solutions with a number of different stationary phases. Kubeck et al. ° used C18 cartridges to adsorb NPEO, but first the water samples were passed through a mixed-bed ion exchange resin to remove all ionic species. Eor SPE of alcohol ethoxylates (AEO) C8 cartridges have been successfully applied from which the surfactants were eluted with methanol followed by... 

The most abundant products among nonionics are ethoxylated alcohols and alkylphenols, polyglycol esters of fatty acids and related compounds having polyoxyethylene chain as hydrophilic group. 

Alkylphenol ethoxylates are important kinds of nonionic surfactants. A characteristic feature of the catalytic ethoxylation of alkylphenols is the enhanced reactivity of phenol hydroxyl for ethylene oxide in comparison with alcohols. Esters of ethylene glycol and alkylphenol behave already as an alcohol. Therefore di-, tri-, and m-mers are allowed to form only after the complete consumption of the starting material. All commercial ethoxylated alkylphenols are mixtures of oligomer-homologues having a Poisson-like distribution with some PEG and catalyst as impurities. Both alkylphenols and dialkylphenols are useful for ethoxylation as a hydrophobic moiety. Among the alkylphenols, isooctylphenol and isononylphenol are most widely used. They are synthesized by the Friedel-Crafts alkylation of phenol with butene dimer and mixture of propene trimers, respectively. 

Features Free of alkylphenol ethoxylates Properties Wh. waxy solid iodine no. < 2 cloud pt. 58-59 C drop pt. 50-60 C pH 6-7.5 (1%) nonionic Toxicology LD50 (oral, rat) > 2000 mg/kg skin irritant Storage Keep in dry storage R.T. 

Another common approach to water-based coating formulations is post-emulsification of a polymer in water. Several condensation polymers, e.g. alkyds, i.e. fatty-acid-modified polyesters, polyurethanes and epoxy resins, have been made into dispersions by the use of a suitable emulsifier and application of high shear. For instance, long oil alkyd resins of the type used in white-spirit-based formulations have been successfully emulsified by using nonionic surfactants such as fatty alcohol ethoxylates, alkylphenol ethoxylates or fatty acid monoethanolamide ethoxylates. Neutralization of alkyd carboxylic groups helps in producing small emulsion droplets and with the proper choice of surfactant, droplet diameters of less than 1 pm can be obtained. Such dispersions are sufficiently stable for most applications. 

Alkylphenol ethoxylates are easier to handle than linear alcohol ethoxylates because they have substantially lower freezing points and have less of a tendency to form gels in aqueous solutions. APEs are also considered to be the lowest-priced nonionic surfactant on the market. 

There are fom basic classifications of textile surfactants cationic, anionic, nonionic, and amphoteric [10]. Overall, usage is about 59% anionic (25% natural soaps, 34% synthetic), 33% nonionic, 7% cationic, and 1% amphoteric [36]. Alkylphenol ethoxylate (APE) surfactants are one of the largest groups of nonionic surfactants, accounting for over 400 million pounds per year in the United States [37]. These fom categories include major product types shown in Table 7.16 [10, 31, 37, 38],... 

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