Two new stable polybrominated salicylanilides for antibacterial use in soap and detergent products

The versatility of two brominated salicylanilides as antiseptic agents and germicides in soap and detergent products for use on skin, hair, hard sur-faces and in fabrics is discussed. Both preparations show stability at elevated temp and pressure and compatibility with many surfactant vehicles. They are free of primary irritation and sensitization, including sunlight-induced irritation. A mixture of di- and tribromosalicylanilide is currently being used in toilet bars, shampoos, laundry products, disinfectant sprays and multi-purpose disinfectant products. The substantivity to fabrics is further characterized by stability to heat and hydrolysis by alkalinity. Essentially pure 3,4′,5 tribromosalicylanilide is resistant to discoloration, making it particularly suitable for use in white and pastel colored toilet bars. It has excellent substantivity to skin and provides long-lasting action against odor-causing and pathogenic bacteria.     

A broad spectrum analysis of the dielectric properties of poly(2-hydroxyethyl methacrylate)

The dielectric permittivity, ε′, and the loss factor, ε″, of dry poly(2-hydroxyethyl methacrylate) were measured using a dielectric analyzer in the frequency range of 0.1 Hz to 100 kHz and between the temperature range of −150 to 275 °C. The dielectric response of the sub-T_gγ transition of PHEMA has been widely studied before but little to no DEA data above 50 °C is present in the literature. In this study the dielectric spectrum is presented up to and above the T_g. The electric modulus formalism is used to reveal the γ, β, α and conductivity relaxations. The apparent activation energies for the relaxations are presented.     

Synthesis and characterization of polyrhodanine/nickel ferrite nanocomposite with an effective and broad spectrum antibacterial activity

Nickel ferrite nanoparticles were successfully synthesized via a co-precipitation approach, and then polyrhodanine/nickel ferrite nanocomposite (PRh/NiFe₂O₄) as an antimicrobial agent was fabricated by a chemical polymerization method. The synthesized NiFe₂O₄ nanoparticles and PRh/NiFe₂O₄ nanocomposite were chemically, magnetically and morphologically characterized using FTIR, FESEM, DLS, VSM and XRD techniques. The FESEM analysis showed that the NiFe₂O₄ nanoparticles had a polygon structure with an average diameter of 50 nm. According to disc diffusion as well as MIC and MBC tests, the PRh/NiFe₂O₄ nanocomposite had better antibacterial effects on killing Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli in comparison with the NiFe₂O₄ nanoparticles.     

Isomerization during hydrogenation of soap. I. Potassium oleate

Potassium oleate in slightly alkaline solution was hydrogenated for up to 7 hr with Rufert nickel catalyst at 150C and 20 kg/sq cm pressure. With 1% catalyst, the iodine value dropped by 12 units in the first hour, and only slightly thereafter. With 2% catalyst there was a drop of 24 units in iodine value in the first hour, a steady state for the next 3 hr, and a second sharp drop of 30 units prior to the seventh hour. Samples of fat hydrogenated over 1% catalyst for 3 hr and 7 hr respectively were analyzed by gas-liquid chromatography, thecis andtrans monoenes were separated by argentation thin-layer chromatography, and the positional isomers in each were determined by oxidation of the total fraction to dicarboxylic acids, which were then estimated by GLC. Apart from double-bond saturation during the first 3 hr of hydrogenation, extensive double-bond migration yielded 23.5% oftrans 8- to 13-monoene, accompanied by small amounts only of positionalcis monoenes other than the starting material. After 7 hr of hydrogenation, extensivecis tocis isomerization occurs, accompanied by lesscis totrans shift; thecis:trans ratio for each monoene consequently tended toward 1:1. The results are explained on the sorption mechanism of hydrogenation and suggest that soap hydrogenation, involving catalyst poisoning, may represent a magnified version of normal fat hydrogenation.     

A new approach to continuous soap making-constant composition control

Summary A new continuous process for the manufacture of soap is described, detailing the three main operations in soapmaking, that is, saponification, washing, and fitting. In the new process all operations involved in the production of soap are carried out in a hermetically closed system. The amounts of lye necessary for the saponification as well as of brine for the washing and fitting operations are regulated by the automatic constant-composition control system, which eliminates the older method of control of the soapmaking process by cumbersome chemical analyses. The process is based on the use of the Hermetic separator, a centrifuge of special design which allows the regulation of the separation efficiency during operation and which prevents any admixture or contact of the soap with air and consequently any oxidation of the product during processing. All type of soap, high grade toilet soap as well as laundry soap and industrial soaps, can be produced by this process, which is characterized by high flexibility, low operation-costs, and a high quality of the finished product. Presented at the fall meeting, American Oil Chemists' Society, Chicago, Ill., October 20–22, 1958.     

Magnetic properties of some new polymeric chelating complexes. I.

A new series of metallopolymer complexes derived from the homopolymer poly(2‐acrylamide) benzoic acid (PBA) through some transition metals, Cu(II), Ni(II), and Co(II), were prepared. The compounds were synthesized and characterized through different techniques. Their molecular structures were assumed based on the different spectral data [ultraviolet (UV) and infrared (IR)]. The magnetic behavior of these metallopolymer complexes was measured as a function of magnetic field strength [1.65–0.85 tesla (T)] at room temperature (RT) (300 K) and as a function of temperature (4.2–300 K) at a magnetic field strength of 1.7 T. Based on the magnetic data, the mechanisms of magnetic interaction are explained and related to the stereochemistry of these metallopolymer complexes. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 409–414, 1999     

Semi-micro analysis of soap. I. Semi-micro determination of the usual constituents

Summary A procedure for the complete semi-micro analysis of soap has been developed. Semi-micro methods are valuable in research work and in legal cases where limited quantities of sample are available. In general, the analytical results obtained on a semi-micro basis and on a macro basis are comparable. Very little special apparatus is required for the semi-micro analysis of a soap, and most of the procedures employed present analogies with the usual methods of soap analysis. By mistake Part II in this series of three articles was published in the September 1948 issue of the Journal, ahead of Part I.     

Microsomal phosphatidic acid phosphohydrolase of rat mammary tissue: I. General properties

The microsomal bound phosphatidic acid phosphohydrolase from lactating rat mammary tissue had a specific activity of six nmoles per mg protein per minute. The optimum pH was 7.0; magnesium at 1.3 mM was required for maximum activity, and at low substrate concentrations magnesium lowered the Km of the enzyme for phosphatidic acid. Diglycerides exerted little effect while diglyceride ether stimulated enzyme activity. Inorganic salts, i.e., potassium phosphate and potassium chloride, enhanced rates of phosphatidic acid hydrolysis under standard assay conditions.     

Facile synthesis and promising antibacterial properties of a new guaiacol-based polymer

A new acrylamide-type monomer (N-(4-hydroxy-3-methoxy-benzyl)-acrylamide) derived from guaiacol was successfully synthesized. Polymers containing guaiacol moiety were obtained via conventional radical polymerization of this monomer with AIBN as initiator. The influence of reaction time, initiator concentration and temperature on polymers characteristics was studied. Evaluation of the termination mode in free-radical polymerization was performed by MALDI-TOF mass spectrometry. Termination occurs mainly by disproportionation reaction. Additional peaks in the spectrum were attributed to side chain reactions implying phenoxy radicals. This new polymer exhibits a potential antibacterial activity against Bacillus subtilis by using anti-adhesion and anti-biofilm tests. After an adhesion time of 3 h, compared to a non-coated glass slide, there was a decrease of bacteria of 99% on the polymer coated glass slide. After three days of culture in a bacterial suspension, no biofilm was observed on the polymer coated surface.     

Studies in the development of antibacterial surfactants. I. institutional use of antibacterial fabric softeners

Summary It has been determined that the incorporation of a highly active antibacterial agent, phenylmercuric propionate, into an aqueous solution of a fabric softener of the quaternary ammonium type results in a most effective antibacterial laundry rinse additive. The presence of the quaternary ammonium compound appears to enhance the antibacterial activity of the mercurial. When applied at a level of 63 parts of available mercurial to one million parts of fabric, the treated cloth is rendered bacteriostatic to several strains ofS. aureus and to ammonia-producing organisms of theProteus group, also mildewstatic toChaetomium globosum. The formulated antibacterial softener as well as the treated linens appear to be entirely safe to humans. In longer-term application tests in a hospital laundry the total bacterial load carried by the soiled treated linens is practically zero. There is no excessive build-up of antibacterial agent on fabric upon repeated applications, and it is readily washed out of the fabric by conventional laundering.     

A Monte Carlo simulation study of the mechanical and conformational properties of networks of helical polymers. I. General concepts

We study the mechanical and conformational properties of networks of helical polymers with a combination of Monte Carlo simulations based on the Wang-Landau algorithm and the three-chain model. We find that the stress-strain behavior of these networks has novel features not observed in typical networks made of synthetic polymers. In particular, we find that as these networks are stretched they first strengthen, then soften and finally strengthen again. This non-monotonic behavior of the stress correlates with the one of the helical content and is rationalized by the elongation-induced formation and melting of the helical structure of the polymer. We complement these results with a study of other conformational properties of the polymer strands that clarify the molecular mechanisms behind the mechanical behavior of these networks. Finally, we present a qualitative comparison of some of our results with the theoretical ones recently reported by Kutter and Terentjev.     

Crazing studies of polystyrene. I. A new phenomenological observation

This paper reports a new phenomenological observation regarding the stress crazing of glassy polystyrene. It was found that the applied stress to initiate a craze, often called the critical crazing stress, is independent of molecular weight. Further, the gross structure of the craze does depend on molecular weight, and other phenomenological aspects previously reported have been reaffirmed. These observations are interpreted in the light of knowledge from the literature and provide a better understanding of the crazing process.     

Surfactant analysis by high performance liquid chromatography: I. A rapid analysis for mixtures of amphoteric surfactants and soap

A method has been developed for the rapid and direct analysis of amphoteric surfactants (sulfobetaines) in combination with mixtures of coconut and tallow soaps, with the aid of reverse phase high performance liquid chromatography (HPLC). The mobile phase consisted of methanol-water (85:15, v/v) with 0.2% by volume acetic acid (pH ≐ 4). At this pH, tallow and coconut soap mixtures are analyzed as the fatty acids and are conveniently separated from the sulfobetaine. A typical HPLC analysis of such mixtures requires 25 min.     

Preparation,surface-active properties and acid decomposition profiles of a new “soap” bearing a 1,3-dioxolane ring

New soap-type surfactants bearing a 1,3-dioxolane ring were prepared in good yields by the acid-catalyzed condensation of 1-O-alkylglycerols (alkyl: decyl, dodecyl, tetradecyl, heptadecyl, octadecyl, orcis-9-octadecenyl) with oxocarboxylic acid esters, followed by alkaline hydrolysis without any expensive reagent and special equipment. These surfactants were soluble in alkaline water at room temperature. Their critical micelle concentrations were much smaller than that of sodium dodecanoate. An alkaline solution of the octadecyl homologue was nonfoaming, but the other homologues, including thecis-9-octadecenyl derivative, showed high foaming ability in alkaline solutions. The structural effect of these compounds on the area per molecule at the surface is also discussed. Because these surfactants contain a 1,3-dioxolane ring, they can be utilized as a new acid-decomposable type of cleavable surfactant. At pH 1, they decompose almost completely into nonsurface-active species after 80 min.     

A new class of transparent polymeric materials. I. Production and properties of an alternating copolymer of N-methylmaleimide and isobutene

An alternating copolymer of N-methylmaleimide and isobutene was produced by a radical precipitation polymerization method. The copolymer thus produced is a new class of transparent polymeric material that shows a unique balance of optical, thermal, and mechanical properties. The visible light transmittance was more than 90% and the stress optical coefficient was smaller than that of polycarbonate, leading to moldings with lower birefringence. The heat deflection temperature of the copolymer was as high as 157°C, and the thermal expansion coefficient was about 30% smaller than those of poly(methyl methacrylate) and polycarbonate. The copolymer showed excellent mechanical properties, specifically, the flexural modulus was the highest among the typical amorphous polymers. © 1996 John Wiley & Sons, Inc.     

Computational Modeling of Silicon Nanoparticle Synthesis: I. A General Two-Dimensional Model

A two-dimensional model has been developed for silicon nanoparticle synthesis by silane thermal decomposition driven by laser heating in a tubular reactor. This fully coupled model includes fluid dynamics, laser heating, gas phase and surface phase chemical reactions, and aerosol dynamics which includes particle transport and evolution by convection, diffusion, thermophoresis, nucleation, surface growth, and coagulation processes. A moment method, based upon a lognormal particle size distribution, and a sectional method are used to model the aerosol dynamics. The simulation results obtained by the two methods are compared. The sectional method is capable of capturing the bimodal behavior that occurs locally during the process, while the moment method is computationally more efficient. The effect of operating parameters, such as precursor concentration, gas phase composition, inlet gas velocity and laser power input, on the characteristics of the particles produced are investigated. Higher temperature generates more large particles with higher precursor conversion. Shorter residence time, from high inlet velocity, produces more small particles at the cost of lower precursor conversion. Increasing H₂ concentration suppresses particle formation by reducing the rates of gas phase and surface reactions, leading to fewer and smaller particles. In addition, the relative importance of the interconnected mechanisms involved in the particle formation is considered. The results make clear that spatial variations in reaction conditions are the primary source of size polydispersity and generation of non lognormal overall size distributions in a laser-driven process like that considered here.     

Development of silver-containing diamond-like carbon for biomedical applications. Part I: Microstructure characteristics,mechanical properties and antibacterial mechanisms

Nanosilver containing diamond-like carbon films with different silver fractions were synthesized by the radio frequency magnetron sputtering using a single silver target in an atmosphere of Ar/CH₄ mixture. The nanocrystalline silver clusters spontaneously segregated within an amorphous diamond-like carbon matrix. The amorphous-to-crystalline phase transformation resulted in both the surface hardness and electrical resistivity of the composite films decreasing with increasing the silver cluster size. The enlarged cluster size also increased the film surface roughness and water contact angle. All the films exhibited an anti-bacterium rate of over 93%, which evidenced that applying these composite films to anti-bacterium surface treatment is effective.     

Soap-based detergent formulations I. Comparison of soap-lime soap dispersing agent formulations with phosphate built detergents

Blends of soap with small amounts of lime soap dispersing agents are efficient detergents in hard water and require little or no tripolyphosphate builder. Lime soap dispersing agents examined include sulfated ethoxylated fatty alcohols, sulfated N-(2-hydroxyethyl) fatty amides, methyl esters of α-sulfo fatty acids, 2-sulfoethyl fatty acid esters and N-methyl-N-(2-sulfoethyl) fatty amides as well as nonionics derived from tallow alcohols. Detergency evaluations were carried out with three commercial soiled cotton cloths as well as by a laboratory multi-wash technique. Formulations containing 80% soap, 10% lime soap dispersing agent and 10% builder gave optimum detergency values. Builder effectiveness was rated tripolyphosphate>silicate (1:1.6)> metasilicate = citrate = oxydiacetate = nitrilotriacetate>carbonate≫sulfate. The detergency of soap-lime soap dispersed combinations compared favorably with a standard brand household heavy duty granular detergent in 50, 150 and 300 ppm hardness water on three soiled cloths. Presented at the AOCS Meeting, Atlantic City, October 1971. East. Market. Nutr. Res. Div., ARS, USDA.     

一种银系抗菌陶瓷釉的制备及性能研究

在釉中引入银系无机抗菌剂，使得陶瓷坯体和陶瓷釉紧密结合，并具有高效杀菌抑菌效果。笔者研制了低温二次烧成具有抗菌功能的乳浊釉陶瓷，采用正交实验法优选出抗菌陶瓷的坯体配方，釉料配方及烧成条件。