Amphoterics, 767 Quaternary compounds

On 100% acrylic materials the quaternary ammonium retarders are used almost exclusively. Other types have been evaluated, however. For example, saturated alkylamines (RNH2 R = C10, C12, C14 and C16 hydrophobes) were found to be just as effective as the quaternary types although other factors, such as aqueous solubility at the optimal dyebath pH and resistance to subsequent discoloration, favour the quaternary compounds [34]- On the other hand, bis (hydroxyethyl) coco amine (12.10) had relatively little effect and the amphoteric carboxymethyldimethylcocoamine (12.11) none at all, although dimethyl-cocoamine oxide (12.12) was quite an effective retarder [34]- Other cationic compounds used [43,44] have included alkylpyridinium salts, imidazoles and imidazolinium salts, alkyldiamines, alkylpolyamines, as well as sulphonium and phosphonium derivatives. 

It is important to note that cationic quaternary compounds (monoquats) are rarely used alone in two-in-one shampoos because their substantivity to hair is either greatly reduced in the presence of anionic detergents [102] or else they form undesired precipitates with anionic surfactants. Therefore, combinations of anionic, nonionic, amphoteric, and zwitterionic surfactants are often employed to minimize the formation of insoluble complexes. 

The major applications of this class of surfactants are shampoos and body washes, and they are often found in conditioning shampoos due to their compatibility with quaternary compounds. The shampoo compositions mostly include from 1 to —8% by weight of amphoterics to help impart aesthetic, physical, or cleansing properties to the composition. Amphoterics also find broad applications in hard surface cleaner formulations and homecare applications, due to their excellent detergency and pH stability. 

A wide variety of quaternaries can be prepared. Alkylation with benzyl chloride may produce quaternaries that are biologically active, namely, bactericides, germicides, or algaecides. Reaction of a tertiary amine with chloroacetic acid produces an amphoteric compound, a betaine. 

Cationic, anionic, and amphoteric surfactants derive thek water solubiUty from thek ionic charge, whereas the nonionic hydrophile derives its water solubihty from highly polar terminal hydroxyl groups. Cationic surfactants perform well in polar substrates like styrenics and polyurethane. Examples of cationic surfactants ate quaternary ammonium chlorides, quaternary ammonium methosulfates, and quaternary ammonium nitrates (see QuARTERNARY AMMONIUM compounds). Anionic surfactants work well in PVC and styrenics. Examples of anionic surfactants ate fatty phosphate esters and alkyl sulfonates. 

The oils and waxes described as lubricants in section 10.10.1, as well as talc, can be used as softeners but have now been superseded by more effective products. These may be non-reactive or reactive and may be cationic, anionic, nonionic or amphoteric. Although many compounds have been patented, by far the most important are cationic quaternary ammonium compounds and various silicones. Until quite recently the field was led by the cationic types but there is now evidence that aminofunctional polysiloxanes have become the most important product group [482]. 

Ion pair mixture QAS + anionic, nonionic, or amphoteric compound, for example, dodecylbenzenesulfonic acid (DDBSA) + quaternary ammonium compound (with appendages <6 carbons) Baker Petrolite (Crosby et al., 2005)... 

The asymmetrical tertiary amines are used exclusively as starting materials for the manufacture of quaternary ammonium compounds, cationic and amphoteric surfactants, and amine oxides. Quaternary ammonium compounds used as bactericides and algicides are produced by the reaction of tertiary amines with benzyl chloride, methyl chloride, or dimethyl sulfate. Of these, the benzyl ammonium chloride salt is the most widely used. 

Fatty acids are raw materials for fatty amines, ethoxylated fatty amines, quaternary ammonium compounds (Quats), fatty acid-polyamine condensates, fabric softeners based on esterquats, fatty add amides, alkyl keten dimers for paper sizing and amphoteric surfactants. Binding of oleic add anhydride to cellulose fibre by chemical grafting is a recently introduced sustainable process to protect construction timber for outdoor use, such as pinewood shutters, from moisture and outside attack. Impregnation of the wood involves two stages firstly in an autoclave, where vacuum and pressure ensure its penetration, and then in a tank where the wood is soaked in a bath of anhydride, to encourage grafting of the anhydride on the wood. ... 

Anionic surfactants are little used in breweries while cationic surfactants such as quaternary ammonium compounds are employed for certain biocidal applications. Ampholytic (amphoteric) surfactants are also used as biocides and like the quaternary ammonium compounds they have to be rigorously... 

Fatty amines and their derivatives represent the most important nitrogen compounds of fatty acids. They possess great ionization constants compared with other alkyl derivatives of ammonia. They are cationic, basic, biologically active, and strongly adsorbed on many surfaces due to their high adsorption potential. They are indispensable in many surface-related physicochemical processes. They are the starting materials for the manufacture of quaternary ammonium compounds and various cationic and amphoteric substances. 

The asymmetrical tertiary amines are used exclusively as starting materials for the manufacture of quaternary ammonium compounds, cationic and amphoteric surfactants, and amine... 

A further class of amphoteric surfactants, which are related to quaternary ammonium compounds, are the alkylbetaines. These are obtained by reacting an alkyldimethylamine with sodium chloroacetate. 

Henrich developed a comprehensive TLC method for identification of surfactants in formulations (4). She specified two reversed-phase and four normal phase systems, with detection by fluorescence quenching, pinacryptol yellow and rhodamine B, and iodine. Prior to visualization, one plate was scanned with a densitometer at 254 nm, and UV reflectance spectra were recorded for each spot detected. Tables were prepared showing the Rf values of 150 standard surfactants in each of the six systems, along with the reflectance spectra and response to the visualizers. This system allows for systematic identification of compounds of a number of surfactant types (LAS, alcohol sulfates and ether sulfates, alkane sulfonates, sufosuccinate esters, phosphate compounds, AE, APE, ethoxylated sorbi-tan esters, mono- and dialkanolamides, EO/PO copolymers, amine oxides, quaternary amines, amphoterics and miscellaneous compounds). Supplementary analysis by normal phase HPLC aided in exactly characterizing ethoxylated compounds. For confirmation, the separated spots may be scraped from one of the silica gel plates and the surfactant extracted from the silica with methanol and identified by IR spectroscopy. 

LAS, alcohol sulfates, ether sulfates, alkane sulfonates, sulfosucci-nate esters, phosphate compounds, AE, APE, ethoxylated sorbitan esters, mono- and dial-kanolamides, EO/PO copolymers, amine oxides, quaternary amines, amphoterics, others identification in formulations... 

Because of their lack of volatility, there are few applications published on the use of GC to directly analyze quaternary amines. Only low molecular weight quaternary amines, far below the surfactant range, can be analyzed directly. Higher molecular weight quats can be analyzed only if they are chemically converted to more volatile compounds. At present, amphoterics can generally not be analyzed directly by gas chromatography without decomposition. 

Fabric softener sheets normally contain quaternaries formulated as their methyl sulfate salts, since the more common chloride salts can be corrosive to the dryer. Sheets usually contain other compounds like acid ethoxylates or amine soaps to optimize properties and performance. Some fabric softeners also contain amphoterics, generally imidazolines rather than quaternary amines. 

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