摘要:

Ultrafiltration studies of solutions of components potentially useful for the formulation of synthetic, waterbased metalworking fluids demonstrates the applicability of the separation method for the removal of dispersed particulate and leak oil contaminants from surfactant solutions, provided these are designed not to form large size micelles or other aggregates

ISSN:0193-2691    

DOI:10.1080/01932699008943233

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

An explanation for the direct role of linoleic acid in barrier function is offered based on the fact that the formation of a crystalline state of the hydrocarbon chains in the stratum corneum lipids strongly reduces or entirely removes the barrier. Addition of linoleic acid to a gel liquid crystalline structure of oleic acid/sodium oleate, a model for stratum corneum lipids, prevents crystallization of the hydrocarbon chains when the water content is reduced. Thus the presence of unsaturation in the fatty acid/soap is not sufficient to prevent cyrstallization, rather inclusion of the essential fatty acid, linoleic acid, will retain the liquid crystalline structure necessary for normal barrier function over a wide range of relative humidities.

ISSN:0193-2691    

DOI:10.1080/01932699008943234

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

Hexyl carbitol has been found to give excellent water solubilizing capacity (42–45%) at high heptane level (41–43%) of w/o microemulsions using only 1% of SDS or CTAB. However, the maximum water solubilization decreased considerably as hexyl carbitol and heptane were replaced by hexyl cellosolve or/and toluene. The latter systems required a much higher concentration of SDS or CTAB. The solubilizing capacities for both systems of hexyl carbitol-heptane-SDS and hexyl carbitol-heptane-CTAB were markedly reduced by the addition of 1.5% NaCl. The effects of the nature of cosurfactant, oil and salinity are explained in terms of interfacial fluidity of the w/o microemulsion droplets.

ISSN:0193-2691    

DOI:10.1080/01932699008943235

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

The use of solid chitin particles for stabilization of oil in water emulsions is evaluated. It was found that the chitin particles can adsorb at the oil water interface, and in view of their surface, properties (γP, γD,) paraffin oil in water emulsions were prepared. Stable emulsions were obtained at high concentration of chitin particles (2.5% w/w) when the water phase contained no surfactants. In the presence of only 0.005% w/w Tween 80, stable emulsions were already obtained at 0.5% w/w chitin. From Zeta potential measurements it was concluded that the stabilization of the above emulsion does not result from changes in the electrical properties of emulsion droplets.

ISSN:0193-2691    

DOI:10.1080/01932699008943236

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

By measuring contact angles with water, glycerol and formamide on a number of polar surfaces, an estimate could be made of the electron-acceptor (γ+) and the electron-donor (γ−) parameters of glycerol (G) and formamide (F), relative to the parameters of. water (W), for which a reference value of γ+W= γ−W= 25.5 mJ/m2has been assumed. The values thus found are: γ+G≈ 3.92 mJ/m2(which yields γ−G≈ 57.4 mJ/m2) and γ+F≈2.28 mJ/m2(which yields γ−F≈ 39.6 mJ/m2).

ISSN:0193-2691    

DOI:10.1080/01932699008943237

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

Empirical “Required HLB” values of unfolded non- electrolytes correspond well (r=0.952) to a new function of the intermolecular free energies of cohesion, calculated from solubility parameters. The equation: Req.HLB=[ (SP+7) /8]4predicts relatively stable oil in water(O/W)macroemulsions for single or multiple ingredient internal phases. Folding of linear aliphatic chains was found to affect predictive results. “Folding corrections” were suggested for both saturated and unsaturated materials.

ISSN:0193-2691    

DOI:10.1080/01932699008943238

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

ISSN:0193-2691    

DOI:10.1080/01932699008943240

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor