Alkylphenols defined

An interesting aspect related to the design of these ensembles is the fine-tuning of the polarity of the inner pores. In this respect, Inumaru et al. reported the adsorption behavior of alkylphenols and alkylanilines by MCM-41 -type solids doped with different degrees of Al3+ and equipped with alkyl chains of different length grafted onto the surface.24,25 The authors found two well defined trends (1) lipophilic guests were... 

ISO 6842 defines total active matter as ethanol solubles, which includes not only the ether sulfate but also alkyl or alkylphenol sulfate, PEG sulfate, and unsulfated nonionic material including PEG (70). ISO 6843 describes wet chemistry methods for separately determining PEG, sulfonated PEG, and inorganic salts in order to arrive at a value for the ether sulfate itself, but this value will still include alkylsulfate or alkylphenolsulfate (71). 

The commercial nonionic surfactants do not absorb radiation in the visible spectrum. The simplest form of spectrophotometric analysis of nonionics is the direct measurement of the UV absorbance of the sample. The ethoxylated alkylphenols are the only compounds which can be readily determined by this method, with a maximal absorbance at about 223 nm and another peak at 276 nm (69). Ethoxylated amides may be determined in model systems by their absorption of light at 202 nm (70), but many other compounds found in typical samples also have absorbance in this region. Because of the sensitivity of direct UV analysis to interference, it can only be used in well-defined situations. Interferences often encountered in nonionic surfactants are oxidation inhibitors like butylated hydroxytoluene. 

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