THE EFFECT OF CERTAIN ADDITION AGENTS ON THE PHYSICAL STATES OF SODIUM SOAPS

1943 ◽  
Vol 21b (10) ◽  
pp. 211-218 ◽  
Author(s):  
Wilfred Gallay ◽  
Ira E. Puddington

The effect of glycerol and of polar and non-polar mineral oils on the density–temperature relations of sodium stearate and sodium oleate have been measured. A non-polar solvent such as a high V.I. oil has no effect, and may be regarded as an inert diluent. Glycerol and low V.I. oils have similar effects on the physical states of the soap. Up to the unidimensional melting point of the soap, the polar solvents have no effect. Above this point, however, an increasing effect is obtained both with increase in temperature and with amount of solvent. The effect is particularly marked above the plasticity point but may be large also in the region of the bidimensional melting point of the soap. The orienting effect of the non-polar hydrocarbon chain on the polar grouping of the soap in the presence of a polar solvent is discussed. The influence of excess acid and alkali in the soap is described.

1943 ◽  
Vol 21b (11) ◽  
pp. 225-229 ◽  
Author(s):  
Wilfred Gallay ◽  
Ira E. Puddington

The surface tension of sodium stearate and sodium oleate dispersions in mineral oils of high and low viscosity index has been measured over a wide range of temperature. In dispersions in the non-polar oil, no surface activity is shown by the soap until the full melting point is reached. In dispersions in an oil of relatively high polarity, surface activity is shown at much lower temperatures corresponding to partial melting points of the soaps. The ability of the soap to lower the surface tension is dependent on the degree of dispersion of the soap, and the relation of surface activity to physical states and phase transitions, previously determined by the authors, is discussed. The addition of glycerol increases the surface activity at a given concentration, but the temperature at which surface activity is attained remains unaffected. Excess fatty acid acts similarly to glycerol; excess alkali decreases surface activity.


Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 1159
Author(s):  
Eskedar Tessema ◽  
Vijayanath Elakkat ◽  
Chiao-Fan Chiu ◽  
Jing-Hung Zheng ◽  
Ka Long Chan ◽  
...  

Phospha-Michael addition, which is the addition reaction of a phosphorus-based nucleophile to an acceptor-substituted unsaturated bond, certainly represents one of the most versatile and powerful tools for the formation of P-C bonds, since many different electrophiles and P nucleophiles can be combined with each other. This offers the possibility to access many diversely functionalized products. In this work, two kinds of basic pyridine-based organo-catalysts were used to efficiently catalyze phospha-Michael addition reactions, the 4-N,N-dimethylaminopyridinium saccharinate (DMAP·Hsac) salt and a fluorous long-chained pyridine (4-Rf-CH2OCH2-py, where Rf = C11F23). These catalysts have been synthesized and characterized by Lu’s group. The phospha-Michael addition of diisopropyl, dimethyl or triethyl phosphites to α, β-unsaturated malonates in the presence of those catalysts showed very good reactivity with high yield at 80–100 °C in 1–4.5 h with high catalytic recovery and reusability. With regard to significant catalytic recovery, sometimes more than eight cycles were observed for DMAP·Hsac adduct by using non-polar solvents (e.g., ether) to precipitate out the catalyst. In the case of the fluorous long-chained pyridine, the thermomorphic method was used to efficiently recover the catalyst for eight cycles in all the reactions. Thus, the easy separation of the catalysts from the products revealed the outstanding efficacy of our systems. To our knowledge, these are good examples of the application of recoverable organo-catalysts to the DMAP·Hsac adduct by using non-polar solvent and a fluorous long-chained pyridine under the thermomorphic mode in phospha-Michael addition reactions.


2004 ◽  
Vol 59 (3) ◽  
pp. 105-112 ◽  
Author(s):  
M. Józefowicza ◽  
J. R. Heldta ◽  
J. Heldta ◽  
J. Heldta

The absorption and fluorescence spectra of 2-methylaminofluorenone (2MAFl) and 2-dimethylaminofluorenone (2DMAFl) were determined at 293 K in a variety of solvents with different polarities. The spectral data were used, in combination with the 2MAFl and 2DMAFl ground state dipole moment (μg), to evaluate μe of the S1 state, to determine the outer-sphere solvent reorganization energy λouter, and the intramolecular reorganization energies: λ1 (associated with vibrations for which hv < kT) and λi(hv > kT). At 77 K the fluorescence spectra in a non-polar solvent are shifted to longer wavelengths. In polar solvents, for both molecules the behavior is opposite. The fluorescence decay data for 2MAFl and 2DMAFl in non-polar solvents are very well fitted by oneexponential functions, while in polar solvents by two-exponential functions. The spectroscopic data distinctly show that both studied molecules in polar solvents form an inhomogeneous emitting system.


1993 ◽  
Vol 56 (6) ◽  
pp. 541-542 ◽  
Author(s):  
P. L. HARRIS ◽  
S. L. CUPPETT

Four commercial emulsifiers, sodium oleate, sodium stearate, sodium stearoyl-2-lactylate, and calcium stearoyl-2-lactylate, were evaluated for their effectiveness as inhibitors of Pseudomonas lipases. Each emulsifier was incubated at 0.5, 1.0, and 2.0% concentrations with the individual as well as a mixture of the crude lipase extracts obtained from three Pseudomonas spp. (P. fluorescens, P. putida, and P. cepacia), in reconstituted nonfat dry milk (10%) for 30 min. At a 2% concentration, all emulsifiers tested were potent inhibitors (100%) of lipase activity. The effectiveness of lipolysis inhibition declined with decreasing emulsifier concentration. Sodium oleate demonstrated significant (P &lt; 0.05) lipolysis inhibition at a 1% concentration regardless of initial lipase level. Synergism in inhibiting lipolytic activity between these selected emulsifiers was not evident.


RSC Advances ◽  
2015 ◽  
Vol 5 (60) ◽  
pp. 48935-48945 ◽  
Author(s):  
Ransi Devendra ◽  
Neil R. Edmonds ◽  
Tilo Söhnel

Organotin carboxylates catalyse aliphatic urethane reaction in polar solvents through an O-coordinated mechanism by forming an alkoxy derivative.


1975 ◽  
Vol 28 (8) ◽  
pp. 1643 ◽  
Author(s):  
MRJ Dack

Internal pressures, (∂U/∂V)T, have been obtained at 25� for the solvents dimethyl sulphoxide, propylene carbonate, formamide, dimethylformamide, acetonitrile, methanol and hexamethyl-phosphoramide by measurement of the thermal pressure coefficients. Data in the literature suggest that values of the internal pressure and the cohesive energy density, (ΔU/Vm), are similar for a non-polar solvent. The observed divergence of the two properties in the polar solvents under investigation is discussed in terms of the nature of the solvent-solvent interactions.


2021 ◽  
Vol 26 (3) ◽  
pp. 1-11
Author(s):  
Sadiq Hasan

  The compound 4-Azido-N-(6-chloro-3-pyridazinyl)benzenesulfonamide was synthesized and studied using FTIR, and 1H-NMR . The influence of a solvent on the experimental 1H-NMR chemical shifts of title compound is discussed. Small chemical shift Δδ < 0.1 ppm were observed when switching from DMSO-d6 to CD3OD. Record a marked change in chemical shifts valeues Δδ > 0.3 ppm when transform from high-polar solvents (DMSO-d6,and CD3OD)  to low-polar solvent (CDCl3). The 1H-NMR chemical shifts of C2-H and C6-H were shown to have excellent linear correlation with the dielectric constants of the solvents DMSO-d6, CD3OD,and CDCl3 (r = 0.995). The 1H-NMR chemical shifts of C18-H shows a perfect relationship with solvatochromic parameter β (r = 0.999).


Author(s):  
Guillaume Falco ◽  
Nathanael Guigo ◽  
Luc Vincent ◽  
Nicolas Sbirrazzuoli

Furfuryl alcohol (FA) is a biobased monomer derived from lignocellulosic biomass. The present work describes its polymerization in presence of protic polar solvents, i.e. water or isopropyl alcohol (IPA), using maleic anhydride (MA) as acidic initiator. The polymerization was followed from the liquid to the rubbery state by combining DSC and DMA data. In the liquid state, IPA disrupts the expected reactions during all the FA polymerization due to a stabilization of the furfuryl carbenium center. This causes the initiation of the polymerization at higher temperature, which is also reflected by higher activation energy. In water system, the MA opening allows to start the reaction at lower temperature. A higher pre-exponential factor value is obtained in that case. The DMA study of final branching reaction occurring in the rubbery state has highlighted continuous increase of elastic modulus until 290 &deg;C. This increasing tendency of modulus was exploited to obtain activation energy dependences (E&alpha;) of FA polymerization in the rubbery state.


Author(s):  
Е.П. Викторова ◽  
Е.В. Лисовая ◽  
М.Р. Жане ◽  
В.И. Мартовщук ◽  
Л.А. Марченко ◽  
...  

Исследован процесс мицеллообразования фосфолипидов соевых лецитинов в неполярных растворителях. Показано, что процесс мицеллообразования характеризуется двумя значениями критической концентрации мицеллообразования ККМ1 и ККМ2 для растворов фосфолипидов соевых лецитинов в модельном масле и CCl4. Отмечено, что межфазное натяжение растворов фосфолипидов в модельном масле при одной и той же концентрации и температуре ниже по сравнению с межфазным натяжением растворов фосфолипидов соевых лецитинов в CCl4, что объясняется большим химическим сродством молекул фосфолипидов и масла. Установлено в результате сравнения значений ККМ1 и ККМ2 фосфолипидов подсолнечных, рапсовых и соевых лецитинов в модельном масле и в CCl4, что способность к мицеллообразованию фосфолипидов соевых лецитинов в модельном масле и CCl4 ниже по сравнению с фосфолипидами подсолнечных и рапсовых лецитинов, что обусловлено различием в указанных лецитинах количественного состава отдельных групп фосфолипидов, в наибольшей степени способных к мицеллообразованию, а также большим содержанием в соевых лецитинах негидратируемых фосфолипидов, представленных комплексами с двух- и трехвалентными металлами. Отмечено, что проявление способности к мицеллообразованию фосфолипидами соевых лецитинов, как и фосфолипидами подсолнечных и рапсовых лецитинов, в CCl4 ниже, чем в модельном масле. Таким образом, подтверждена эффективность применения CCl4 в качестве неполярного растворителя, позволяющего снизить степень мицеллообразования фосфолипидов соевых лецитинов для разработки способа определения кислотного числа соевых лецитинов с применением импульсного метода ядерного магнитного резонанса. The process of micelle formation of soy lecithin phospholipids in non-polar solvents was studied. It is shown that the process of micelle formation is characterized by two values of the critical concentration of micelle formation KCM1 and KCM2 for solutions of soy lecithin phospholipids in model oil and CCl4. It is noted that the interfacial tension of phospholipid solutions in the model oil at the same concentration and temperature is lower compared to the interfacial tension of soy lecithin phospholipid solutions in CCl4, which is explained by the large chemical affinity of the phospholipids and oil molecules. As a result of comparing the KKM1 and KKM2 values of phospholipids of sunflower, rapeseed and soya lecithins in model oil and in CCl4, it was found that the ability to micelle formation of phospholipids of soya lecithins in both model oil and CCl4 is lower compared with sunflower and rape phospholipids, which the difference in the indicated lecithins in the quantitative composition of individual groups of phospholipids that are most capable of micelle formation, as well as the high content of non-hydratable phospholipids in soya lecithins, represented by complexes with bivalent and trivalent metals. It was noted that the manifestation of the ability to micelle formation by soy lecithin phospholipids, as well as sunflower and rapeseed lecithin phospholipids in CCl4 is lower than in model oil. Thus, the effectiveness of the use of CCl4 as a non-polar solvent has been confirmed, which allows to reduce the degree of micelle formation of soy lecithin phospholipids for the development of a method for determining the a


1960 ◽  
Vol 38 (12) ◽  
pp. 2395-2401 ◽  
Author(s):  
R. F. Grant ◽  
B. A. Dunell

The proton magnetic resonance absorption in anhydrous sodium stearate has been investigated over the temperature range −182 °C to 200 °C. An abrupt change in the line width and the second moment has been observed between 113 °C and 114 °C, which corresponds to a known phase transition. The results suggest that at temperatures below 114 °C the motion of the hydrocarbon-chain portion of the sodium stearate molecule is chiefly one of oscillation or rotation about the chain longitudinal axis. The hydrocarbon chains may be free to move about other axes at temperatures above 114 °C, although the molecule as a whole retains a fixed position in the crystal lattice.


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