Lithium laurate

The surface and interfacial tension of a great number of ester sulfonates has been measured by Stirton et al. [26-28,30]. The values of the surface tension of 0.2% solutions at 25 °C are in the range from 25 to 50 mN/m and from 2 to 20 mN/m for the interfacial tension. In the group with the same number of C atoms the pelargonates and laurates have the lowest values. Among the esters of the same a-sulfo fatty acid, the surface and interfacial tension decreases with increasing molecular weight of the alcohols. Surface tension values also depend on the cation. For the alkali salts the values decrease from lithium to sodium to potassium. 

Wherever possible, the soaps and surfactants were added to the natural rubber latex as dilute aqueous solutions. The cases where this was not possible were (a) ethylene oxide-fatty alcohol condensates of low ethylene oxide fatty alcohol mole ratio, and (b) sparingly-soluble fatty-acid soaps such as lithium laurate and calcium soaps. The former were added as pastes with water, the latter as dry powders. In all cases, the latex samples were allowed to mature for about three days at room temperature before their mechanical stabilities were determined. This allowed some opportunity for the attainment of adsorption equilibrium. 

Counterion effects (5). Experiments which have been carried out using lithium, sodium, potassium, ammonium and morpholinium laurates have shown that the effects of these five laurates upon mechanical and chemical stability are broadly similar, although such differences as are observed are statistically significant. 

The results for effects upon mechanical stability are summarised in Table II. That lithium laurate behaves similarly to, say, potassium laurate is perhaps surprising, in that it is known that a lithium salt is mor ffective in reducing the mechanical stability of natural rubber -ftian is the corresponding potassium salt (6.). The inference has been drawn that the counterion of the car-boxylate soap has a negligible effect upon the ability of the soap to enhance mechanical stability, relative to the effect of the anion, at least for those cations for which specific adsorption effects are absent. 

Some data are also available for the effect of the counterion of a dodecyl sulphate upon its ability to enhance the mechanical stability of natural rubber latex. As in the case of the laurates the lithium, sodium, potassium and ammonium salts are similar in behaviour, but the morpholinium salt is slightly less effective. Again, the latter effect is attributed to specific adsorption of the morpholinium cation. Calcium and magnesium dodecyl sulphates are also effective in enhancing mechanical stability, their abilities being similar to that of morpholinium dodecyl sulphate. 

Several other pyrolytic studies were performed on nylon 6. In one such study [4], the influence of several aliphatic carboxylates on nylon 6 thermal degradation was studied. The carboxylates that were evaluated include sodium butyrate, sodium caproate, sodium a-ethylcaproate, sodium caprylate, sodium laurate, potassium caproate, potassium laurate, and lithium caproate. Small amounts of these aliphatic carboxylates strongly increase the thermal decomposition rate even at 280° C. The effect of aliphatic carboxylates can be explained by the deprotonation of one of the amide groups of the polymer followed by the nucleophilic substitution of a neighboring carbonyl group, in a reaction as shown below ... 

Haro Chem ALT. See Aluminum tristearate Haro Chem BG. See Barium stearate Haro Chem BSG. See Barium laurate Haro Chem CBHG. See Calcium behenate Haro Chem CGD, Haro Chem CGL, Haro Chem CGN] Haro Chem CPR-2 Haro Chem CPR-5. See Calcium stearate Haro Chem CSG. See Calcium laurate Haro Chem KPR. See Cadmium stearate Haro Chem KS. See Cadmium laurate Haro Chem LHG. See Lithium 12-hydroxystearate... 

Haro Chem ZSG. See Zinc laurate Haro Gei ALMD-2] Haro Gei ALT. See Aluminum stearate Haro Gei LHG. See Lithium 12-hydroxystearate... 

Ethylene/acrylic acid copolymer Glyceryl stearate SE Hydrogenated menhaden oil Hydrogenated soybean oil Hydrogenated tallowtrimonium chloride Isocetyl laurate Isocetyl myristate Isocetyl stearate Laurate canola oil d-Limonene Lithium stearate Mica Palm (Elaeis guineensis) oil PEG-90 PEG-7 glyceryl cocoate PEG-2M PEG-8 sesquioleate PEG-100 stearate Polyethylene, oxidized... 

Bis (octylthio)-s-triazin-2-yl] amino]-2,6-di-t-butylphenol C13-15 pareth-20 Lithium 12-hydroxystearate Polyglyceryl-10 tetraoleate Propylene glycol laurate Propylene glycol ricinoleate... 

Sodium octyl sulfate Steareth-5 Steareth-15 Steareth-40 Sucrose laurate Xanthan gum stabilizer, thermosets Lithium 12-hydroxystearate stabilizer, tin-sulfur compounds Isooctyl thioglycolate stabilizer, tobacco... 

Dibutoxyethyl adipate Di (2-ethylhexyl) peroxydicarbonate Mannitan laurate Sorbitan laurate C18H34O7S Na Diheptyl sodium sulfosuccinate C18H35CIO earoyl chloride C18H35KO2 Potassium stearate Ci8H35Li02 Lithium stearate CisH LiOs... 

In the survey article [174], devoted to a generalization of the data on the use of soaps for the stabilization of pol3rvinyl chloride, it is noted that in recent years salts of inorganic acids have been gradually displaced by soaps, the most widespread among which are lead stearate and barium and cadmium laurates. Salts of lead, tin, barium, calcium, cadmium, strontium, sodium, and lithium of such acids as formic, oxalic, maleic, caprylic, imdecylenic, lauric, stearic, ricinoleic, etc., have... 

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