Calcium Ion Stability Research Articles

Effect of Moringa stenopetala leaf extracts on the physicochemical characteristics and sensory properties of lagered beer.

Flavor instability resulting from beer storage and oxidation is the most important quality‐related problem in the brewing industry. This study evaluated the influence of adding 80% ethanolic extract of Moringa stenopetala leaf to lagered beer at 400, 600, and 800 ppm concentrations for 30‐, 60‐, and 90‐day storage time at room temperature. The effect of physicochemical properties of the beer incorporated with leaf extract of Moringa stenopetala (LEMS) was evaluated using the American Society of Brewing Chemists method of analysis. Sensory acceptability of the beer treated with LEMS was evaluated using nine hedonic scales over a period of storage time. Original gravity (11.06–11.08), apparent extract (3.68–3.77), pH (4.23–4.40), vicinal diketone (0.07–0.09), and alcohol content (4.76–4.81) were not altered by the incorporation of LEMS at any level of treatment and over a period of storage time. The beer color (8.88–9.70 EBC), bitterness (13.62–15.56 bitterness unit), calcium ion (44.18–52.04 ppm), and foam stability (201.5–246.5) of beer increased with increasing LEMS concentration, but a significant haziness reduction (1.23–0.63) was observed. However, the storage time decreased both haziness and foam stability of LEMS‐incorporated beer. The incorporation of LEMS at an optimum level kept its quality for 90 days better than the usual antioxidant (potassium metabisulfite) added in beer. The sensory analysis also supported the beer treated with 600 ppm of LEMS as the best overall acceptability. The result indicates a promising use of LEMS as a functional ingredient in beer to reduce beer oxidation probability and keep its freshness for a period of storage time.

Preparation and characterisation of novel cross-linked poly (IBOMA-BA-DFMA) latex

Purpose – The purpose of this research was to synthesize a novel cross-linked latex copolymerised by butyl acrylate (BA), isobornyl methacrylate (IBOMA), hydroxy propyl methacrylate (HPMA) and dodecafluoroheptyl methacrylate (DFMA). IBOMA is a very useful functional monomer. Its molecular structure not only contains bornyl acetate alkoxy but also includes a double bond, which can be copolymerised with other unsaturated monomers via free radical polymerization. The large nonpolar bicyclic alkyl in bornyl acetate alkoxy offers the polymer chain strong space steric protection, which endows the polymer with some special properties. Design/methodology/approach – The semi-continuous seeded emulsion polymerisation technology was adopted to copolymerise BA, IBOMA, HPMA and DFMA in the water phase, which was initiated with potassium persulfate (KPS) and emulsified with the mixed surfactants of sodium dodecyl sulphate (SDS) and OP-10. Findings – The particle size of the latex decreases with an increase in the amount of IBOMA. All the latexes have good mechanical stability and calcium ion stability. The latex has good film-forming property when the IBOMA amount is controlled moderately. The optimal IBOMA amount is 10.00 g. The thermal stability and water resistance of the film are improved. Practical implications – The latexes can be applied as a binder of coatings and adhesions. Originality/value – The effect of the amount of IBOMA and BA on the properties of the resultant latex and its film were investigated in detail. In comparison with the latexes copolymerised without IBOMA, the novel latex has better thermal stability and water resistance.

Stability and Mechanical Properties of Hard/Soft Latex Blends

In this contribution, hard/soft latex blends were prepared by mixing proportionable non-crosslinkable hard and self-crosslinkable soft latices. The stability and mechanical properties of latex blends were comparatively studied with the neat latex with high glass transition temperature (Tg). It was found that the calcium ion stability of the latex blends is better than neat hard latex. In addition, the stress at break decreased with the increasing of φs (mass fraction of soft particle in latex blends) and the break elongation increased when φs below 0.8. Meanwhile, the value of tensile stress and break elongation of the hard latex film with coalescing agent, DPnB, additive is between that of the latex blends film with 60% and 70% soft particle. The study on viscoelasticity of the latex films demonstrated that this composite latex can be considered as phase separation blend involving a soft phase filled with hard spheres. The results indicate that the soft latex can serve as the substitution of coalescing agents in water-based ink industry to obtain low or zero VOC ink, without compromise on properties.

Characterisation and Properties of Fluorinated Acrylic Latex Prepared with Mixed Surfactants of Sds and Apg

The nonionic emulsifier of OP-10 is often used in preparing the latex. OP-10 belongs to a type of NPEOs. However, NPEOs are bioaccumulative and persistent in the environment while nonylphenol, the breakdown product of NPEs, is an endocrine disruptor. Therefore, the EU Commission has recommended implementing a risk reduction strategy, which foresees the ban of all applications leading to direct emissions to waste water and strict emission controls for all other technical processes using NPEOs as surfactants. The aim of the research is to study the possibility that OP-10 is replaced by APG to prepare the fluorinated acrylic latex. The fluorinated acrylic latex was prepared successfully via semicontinuous seeded emulsion polymerization of butyl acrylate (BA), methyl methacrylate (MMA) and hexafluorobutyl methacrylate(HFMA) in water phase initiated with potassium persulfate (KPS) and emulsified with the aid of mixed surfactants of sodium dodecyl sulfonate (SDS) and alkyl polyglucosides (APG). The structure of the resultant latex is confirmed by Fourier transform infrared spectroscopy (FTIR) spectrum. The influences of the amount of APG on the properties of the resultant latex and its film were investigated in detail. Results show that the particle size is decreased with the increase amount of APG. However, the calcium ion stability of the latex is increased with the increase of amount of APG.

Preparation and evaluation of some amide ether carboxylate surfactants

A homologous series of new mild surfactants, namely: Alkyl amide ether carboxylates surfactants (AEC) RCO–NHCH2CH2O (CH2CH2O)6CH2COONa, were synthesized by esterification, amidation, ethoxylation and carboxymethylation reaction steps of fatty acids (Lauric, Myristic, palmitic, stearic, oleic or linoleic). The chemical structures of the prepared compounds were confirmed using different spectroscopic techniques, FTIR spectroscopy, mass spectra and HNMR. The surface properties including surface and interfacial tensions, foaming height, emulsification power, calcium ion stability, stability to hydrolysis and critical micelle concentration (cmc) were determined. The study of their surface properties showed their stability in hard water and in acidic and alkaline media. These compounds have high calcium ion stability. The low foaming power could have an application in the dyeing auxiliary industry. The lower values of the interfacial tension values indicate the ability of using these surfactants in several applications as corrosion inhibitors and biocides. The data revealed various advantages and potentials as a main surfactant as well as co- surfactants.

Synthesis and Properties of Some N-Acylethylenediamine Triacetic Acid Chelating Surfactants

Abstract A new kind of surfactants with chelating properties named N-acylethylenediamine triacetate (N-acyl ED3A) of different hydrocarbon chain lengths were synthesized from anhydrous ethylene diamine, fatty acid chlorides (Capryloyl, lauroyl, myristoyl, palmitoyl, stearoyl or oleoyl chloride) and chloroacetic acid. The chemical structures of the prepared compounds were confirmed using different spectroscopic techniques, primarily Fourier transform infrared spectroscopy and nuclear magnetic resonance. The surface properties including surface and interfacial tension, foaming height, emulsification power, calcium ion stability, stability to hydrolysis and critical micelle concentration (CMC) were determined. The trisodium N-acylethylenediamine triacetates have been found to combine the properties of strong surfactancy, extreme mildness with a high tolerance to water hardness, and ability to chelate metal ions, which indicates a promising application prospect in many fields.

Synthesis and Physicochemical Properties of Dipeptide Type Surfactants: I N-Dodecanoylglutamyl-glutamic acid and glutamyl-aspartic acid.

An attempt was made to synthesize dipeptide-type surfactants analogs from glutamic acid and aspartic acid, which are naturally occurring and renewable amino acids. N-Lauroylglutamic anhydride was used as a raw material for the synthesis. In this study N-lauroylglutamyl aspartic acid (LGA) and N-lauroylglutamyl glutamic acid (LGG) were prepared. Physicochemical properties such as the solubility, the lowering surface tensions, the foaming ability, the emulsification potential, and the higher order structure of the surfactant aggregates were discussed with changing the neutralization of the tri-basic carboxylic acid in the surfactants. These surfactants showed an outstanding surface tension lowering ability. Surface tension and cmc of the aqueous solution of LGA increased as the neutralization of three carboxylic acids increased. On the other hand, those of LGG didn’t show the similar behavior. This difference would result from the inequality in the hydrophobicity produced by one more methylene groups between LGA and LGG. It should bring about some changes such as electrostatic repulsion between two negatively charged carboxylate anions, the inter- and intrahydrophobic interactions and the hydrogen bonds. It was confirmed that these surfactants possessed an excellent biodegradability, a high stability for the hydrolysis, high calcium ion stability. Introduction of the peptide linkage that bonds the two amino acids did not affect the hydrolysis stability of the surfactant. Neither LGG nor LGA were hydrolyzed in basic (pH=10) aqueous solution for one month. At the same time, they showed a high moisturizing effect in addition to a low protein denaturation potential.

ChemInform Abstract: SOAP‐BASED DETERGENT FORMULATIONS‐ XIX. AMPHOTERIC ALKYLSUCCINAMIDE DERIVATIVES AS LIME SOAP DISPERSANTS

A series of amphoteric surfactants was synthesized by reaction of 1,3-propanesultone with N-alkyl-N′-(ω,ω-dimethylaminoalkyl)succinamides. The intermediate succinamides were prepared by reacting methyl N-alkylsuccinamates, obtained from alkylamines containing 8 to 18 carbon atoms, with N,N-dimethyl-1,3-propylenediamine or N,N-dimethylethylenediamine neat. The amphoterics were isolated as hygroscopic crystalline solids having superior lime soap dispersing ability, water solubility, and calcium ion stability. Detergency studies at 0.2% concentration (300 ppm water hardness) indicated good washing ability when used alone and excellent performance in combination with soap or in soap-silicate formulations.

Soap‐based detergent formulations: XXII. Sulfobetaine derivatives ofN‐alkylglutaramides and adipamides

Abstract and SummaryThe acid chlorides of methyl hydrogen glutarate and methyl hydrogen adipate were allowed to react with various primary fatty amines. The resulting amido esters were converted into the corresponding amino diamides by sodium catalyzed reaction with N,N‐dimethylaminoalkylamines. The desired sulfobetaines were obtained by reaction of the resulting N‐alkyl‐N′‐(1,1‐dimethylaminoalkyl) glutaramides and adipamides with 1,3‐propanesultone. The compouds possess the same excellent lime soap dispersing ability, water solubility, calcium ion stability, and detergency properties as the analogous succinamide derivatives previous reported. This indicates that the spacing between the two amido groups or that between the quaternary nitrogen atom and the nearest amido group does not affect surface active properties.

Soap‐based detergent formulations: XIX. Amphoteric alkylsuccinamide derivatives as lime soap dispersants

Abstract and SummaryA series of amphoteric surfactants was synthesized by reaction of 1,3‐propanesultone with N‐alkyl‐N′‐(ω,ω‐dimethylaminoalkyl)succinamides. The intermediate succinamides were prepared by reacting methyl N‐alkylsuccinamates, obtained from alkylamines containing 8 to 18 carbon atoms, with N,N‐dimethyl‐1,3‐propylenediamine or N,N‐dimethylethylenediamine neat. The amphoterics were isolated as hygroscopic crystalline solids having superior lime soap dispersing ability, water solubility, and calcium ion stability. Detergency studies at 0.2% concentration (300 ppm water hardness) indicated good washing ability when used alone and excellent performance in combination with soap or in soap‐silicate formulations.

Synthesis of Maleic Monoesters of Oxyethylated Alcohols and Properties of Their Sodium Salts

A series of maleic monoesters of mono and trioxyethylated 1-dodecanol, 2-dodecanol, 6-dodecanol, 1-tetradecanol, 2-tetradecanol, and 7-tetradecanol was synthesized. The cmc, surface tension reduction, calcium ion stability, and lime soap dispersing power of their sodium salt solution were determined. The introduction of oxyethylene groups caused the decrease of cmc and markedly improved the calcium ion stability. On heating the calcium soap solution, the cloud points were observed. The influence of oxyethylene groups on the cmc and the calcium ion stability was discussed in terms of the hydration of oxyethylene groups and the complexation of oxyethylene groups in micelle with metal ion.

ChemInform Abstract: SOAP‐BASED DETERGENT FORMULATIONS. XVI. SURFACE ACTIVE SULFOSUCCINIMIDES

AbstractDie Sulfosuccinimide (III) und (VII) werden auf dem beschriebenen Weg dargestellt.

Soap‐based detergent formulations: XIV. Amphoteric derivatives of alkylbenzenesulfonamides

AbstractSurface active amphoteric derivatives were prepared from alkylbenzenesulfonyl chlorides. Industrial detergent alkylates, as well as benzene and pure 1‐phenylalkanes whose side chains ranged from C1 to C12, were used as starting materials in this study of chemical structure‐physical property relationships. The alkylbenzenes were first converted into the corresponding alkylbenzenesulfonyl chlorides with chlorosulfonic acid, and the sulfonyl chlorides were further treated with N,N‐dimethyl‐1,3‐diaminopropane or N,N‐bis‐(2‐hydroxyethyl)‐1,3‐diaminopropane. The reaction products were quaternized with propanesultone to produce amphoteric surfactants in high yields. The N,N‐dimethyl herivatives of pure phenylalkanes were white crystalline powders, whereas the N,N‐bis‐(2‐hydroxyethyl) derivatives were light , lime soap dispersing requirement, surface tension, wetting ability, and calcium ion stability were determined. The commercial detergent alkylate derivatives showed good detergency by themselves as well as in formulations with soap or with soap and silicate builder. Good lime soap dispersing properties were observed with compounds possessing a side chain of at least 4 carbon atoms.

Soap‐based detergent formulations. XVI. Surface active sulfosuccinimides

AbstractA series of sodium N‐alkylsulfosuccinimides and N‐acyloxymethylsulfosuccinimides were prepared by reaction of the corresponding N‐alkylmaleimides and N‐acyloxymethylmaleimides with sodium bisulfite in aqueous ethanol. The N‐alkylmaleimides were prepared by dehydration of N‐alkylmaleamic acids with acetic anhydride and fused sodium acetate. The N‐acyloxymethylmaleimides were obtained by reaction of an acyl chloride with N‐methylolmaleimide in a pyridine‐acetone solvent. The surface active properties of the sulfonated derivatives showed them to be efficient lime soap dispersing agents with good calcium ion stability but relatively high Krafft points. The 2 types of compounds exhibited similar detergency characteristics under the conditions employed and were generally comparable to the control on a cotton‐polyester blend when used alone and in a ternary formulation with soap and silicate builder on cotton test cloths.

Surface active N‐acylglutamate: III. Physicochemical properties of sodium long chain N‐acylglutamates

AbstractThe physicochemical properties of sodium long chain N‐acylglutamate (AGSn) are described. The wetting power, emulsifying power, dispersing power and calcium ion stability were measured. Monosodium N‐lauroyl‐l‐glutamate (l‐LGS) had good wetting and emulsifying properties, but disodium N‐acylglutamate (AGS2) was inferior tol‐LGS in those properties. In the dispersing power using carbon black as powder,l‐LGS was inferior but AGS2, having a palmitoyl or stearoyl radical, was excellent. The AGSn with a few exceptions had good calcium ion stabilities.

Soap‐based detergent formulations: IV. The synthesis and surface active properties of sulfopropyl esters of N‐substituted iminodiacetic acids

AbstractA series of di(potassium 3‐sulfopropyl) N‐alkyl and N‐acyliminodiacetates were prepared by reacting 1,3‐propanesultone with the corresponding dipotassium N‐alkyl and N‐acyliminodiacetates, respectively. The washing ability of these products was examined alone and in combination with soap. Whereas the surfactant properties of the precursor iminodiacetates were poor, the addition of two sulfopropyl groups resulted in products with excellent lime soap dispersing power, calcium ion stability and water solubility.

Properties of aqueous solution of sodium cyclododecyl sulfate

AbstractSodium cyclododecyl sulfate was prepared from cyclododecyl alcohol and chlorosulfonic acid to investigate the physical and surface active properties of the surfactant. Its Krafft point, critical micelle concentration (CMC), surface tension, emulsifying power, wetting time and dispersing power were examined and compared with those of sodium dodecyl sulfate which has a linear structure and contains the same number of carbon atoms in the hydrophobic portion. The sodium cyclododecyl sulfate, in contrast to the sodium dodecyl sulfate, had a higher (about two times) Krafft point, much larger (about 10 times) CMC, showed the same excellent wetting property, but exhibited lower emulsifying power. Also the sodium cyclododecyl sulfate is more insoluble (as shown by the Krafft point) than the sodium dodecyl sulfate, while calcium ion stability of the cyclododecyl sulfate surfactant is greater than that of the linear anionic surfactant.

The Properties of Aqueous Solutions of Sodium 2-Sulfoethyl Alkanoates and Sodium Alkyl β-Sulfopropionates

Abstract A series of sodium 2-sulfoethyl alkanoates RCOO(CH2)2SO3Na was prepared from sodium isethionate and fatty acids containing 9, 11, 13, and 15 carbon atoms. The Krafft point, the critical micelle concentration (CMC), the surface tension, the emulsifying power, the wetting time, the resistance to acid hydrolysis, and the calcium-ion stability of this series of surfactants were examined, and the results were compared with those of the corresponding sodium alkyl β-sulfopropionates ROCO(CH2)2SO3Na, which have another structure of ester-linkage. The CMC values of sodium 2-sulfoethyl alkanoates almost coincide with those value of the sodium alkyl β-sulfopropionates with the same number of carbon atoms. However, the Krafft point and surface tension at the CMC of sodium 2-sulfoethyl alkanoates were lower than those of the sodium alkyl β-sulfopropionates with the same number of carbon atoms. Sodium 2-sulfoethyl alkanoates are more stable than sodium alkyl β-sulfopropionates in their resistance to hydrolysis and to the calcium-ion.

Preparation and properties of sodium alkyl β‐sulfopropionates

AbstractA series of sodium alkyl β‐sulfopropionates containing 11 to 17 carbon atoms was prepared from β‐bromopropionic acid, sodium sulfite and even‐numbered straight chain alcohols of 8 to 14 carbon atoms. The Krafft point, critical micelle concentration (cmc), emulsifying power, calcium ion stability and resistance to acid hydrolysis were determined. Sodium alkyl β‐sulfopropionates, in which the ester linkage (hydrophilic group) is moved toward a more central position in the alkyl chain, have higher cmc values and lower Krafft points than the corresponding sodium alkyl sulfoacetates. The sodium alkyl β‐sulfopropionates were less stable toward hydrolysis than the sodium alkyl sulfoacetates because the adjacent sulfo group in the sulfoacetates protects the ester linkage through steric hindrance. The emulsifying power increases, but the calcium ion stability decreases, with increasing alkyl chain length for a series of sodium alkyl β‐sulfopropionates.

Determination of Calcium Fractions of Serum. II. Investigation of Calcium Ion Activity and Stability of Important Calcium Complexes by an Improved Semimicro Method

A two wavelength spectrophotometric method using tetramethylmurexide for assay of ionized calcium is described. Thermostating at 10° C and strict wavelength control have given high reproducibility and sensitivity. Calcium and indicator combine in a 1:1 ratio. A calcium ion activity coeffi cient curve as function of ionic strength is given. Stability constants for complexes of calcium and citrate, phosphate, sulphate, and lactate agreed with values obtained by more rigorous techniques.