Beiträge zum maschinellen Geschirrspülen 1. Mitteilung: Entfetten von Glasoberflächen unter den Bedingungen des maschinellen Geschirrspülens

Contributions on Mechanical Dish Washing 1: Defatting of Glass Surfaces Under the Conditions of Mechanical Dish Washing Tracer technique was used to study the dissolution of a film of butter fat or lard from glass surface during the conditions used in mechanical dish washing. Washing temperature was found to be the determining factor in the removal of fat residue. The major amount of the fat can be dissolved only at temperatures above its melting point, and, sufficient amounts of the cleansing agent ensure its stable emulsification, thus preventing the redeposition on the glass. Hot prewashing reduces the requirement of cleansing agent, since the quantity of cleansing increases linearly with the fat level of the goods to be washed. Polyethylene, because of its higher affinity to fat, is more difficult to defat than glass.     

Beiträge zum maschinellen Geschirrspülen 2. Mitteilung: Entfernen von Stärkerückständen von Glasoberflächen

Contributions on Mechanical Dish Washing 2: Removal of Starch Residues from Glass Surfaces The use of ¹⁴C-labelled tobacco starch as indicator of potato starch enabled to study the removal of starch residues from glass surface by mechanical dish washing. It was found that the amount of starch applied could be reduced to as much as 11.5% during prewashing with cold tap water. The use of prewashing water at 45°C improves the swelling of dried starch residues. In contrast to removal of fat, the removal of starch residues requires a washing temperature of at least 55°C. However, even after an optimum combination of washing temperature, washing time and amount of cleansing agent, higher proportions of starch residues are retained on the glass surface than fat residue. At a maximum washing temperature of at least 50°C, the amount of starch residue remaining on the cleaned glass surface is greatly independent of the amount of starch applied to the glass surface.     

Das Verhalten von Glas beim maschinellen Geschirrspülen

The Behaviour of Glass in Mechanical Dish-Washing Under the conditions involved in mechanical dish-washing there is only a slight difference in the behaviour of glasses of different compositions. The higher temperatures attained thereby are mostly responsible for the damages to the glass. Alkaline, especially strongly alkaline solutions, attack more than the acidic ones. The percentage of the complaints lodged for the glass damages is still relatively small. However, the rapidly increasing number of household dish-washing machines makes it necessary that everybody concerned should discuss the problem of cloudiness of glass.     

Beiträge zur Schaumreinigung fester Oberflächen 2. Mitteilung: Schaumeigenschaften und Wirksamkeit

Foam Cleaning of Solid Surfaces 2. Foam Properties and Effectiveness Cleaning foams are very stable. Although the foam gives up almost the entire amount of liquid entrained in the lamella within 20 min, the original volume is retained. The highly alkaline solution released wets the soiled surface of the tile, swells the dried up protein rest and dissolves the same, which is subsequently removed by rinsing with water. The effectiveness of foam cleaning can be increased by up to 10% using longer periods of action of the foam on the soiled surface. Mechanical and heat treatment are of limited value in foam cleaning.     

Beiträge zur Schaumreinigung fester Oberflächen, 1. Mitteilung: Experimentelle Grundlagen

Foam Cleansing of Solid Surfaces 1. Experimental Basis In addition to the rinsing and spraying processes, mainly carried out for cleansing in food processing plants, the process of foam cleansing might gain importance, especially for the treatment of wall surfaces or the outer side of plants. Therefore, a method for testing the efficiency of foam cleansing using a model tiled wall has been developed. An aqueous dispersion of casein, according to Hammersten, and soot is used as soil which is sprayed on the tiles. The effect of cleansing is quantitatively assayed by measurement of brightness by the remission technique. Advantages, limits and accuracy of the method are discussed.     

Stand der Technik beim manuellen und maschinellen Geschirrspülen

Situation of the Technology in Manual and Mechanical Dish Washing The mode of action of the modern dish washing agents for manual washing depends on its content of neutral surface active agents. On the other hand, in the dish washing machines alkaline washing agents and acid or neutral rinsing agents are used. Health hazards due to the washing agent remaining on the dishes are not to be feared.     

Beiträge zum Vernetzungs- und Abbauverhalten von Acrylelastomeren

The aim of this investigation was to obtain additional knowledge of the curing mechanism and the aging properties of acrylic polymers containing active chlorine. These were cured with amine or metal-soap/sulphur combinations. For this purpose, we used sulphur, chlorine, and nitrogen analyses, together with measurements of crosslink density and stress-relaxation. These investigations were partly made with vulcanisates based on technical acrylic polymers, and partly with crosslinked products of homo- and copolymers containing chlorine. Using the amine curing system, the diamine, after vulcanisation, is completely incorporated. Curing with metal-soap/sulphur combinations sulphur crosslinks are formed. The crosslink density is proportional to the concentration of amine or potassium-stearate in the compound. Comparing polyethylacrylate polymers containing vinyl-chlorecetate and 2chloroethyl-vinylether comonomers one always h d s the higher crosslink densities in polyethylacrylat/vinylchloracetat copolymers. We proved by stress relaxation measurements that scission of the network occurs at the crosslinks during air aging. Using amine as the curing agent oxidativedegradation exceeds the thermal one. In case of metal-soap/sulphur curing system thermal degradation exceeds the oxidative portion. Remarkable differences in aging properties between the two types of polymers could not be found. These results fit with our conception of the types of networks built up duringvulcanimtion, based on the other examinations.     

Beiträge zur Untersuchung und Beurteilung von naturbelassenen Sonnenblumenölen

Investigation and Adjudgement of Sunflower Oils of Natural Purity Colour reactions, which were employed till now and found suitable for differentiating unrefined from refined sunflower oils are reported. The qualitative detection of the substances responsible for the colour reaction can be carried out with unsaponifiables, however, it is also possible to use the oil directly after a certain enrichment. Under the experimental conditions chosen, and using antimony trichloride spray the pressed oils give two blue spots with similar Rf-values on the thin-layer chromatogram located slightly above the start. These substances giving a blue colour, which were found to be keto-steroids, were absent in refined sunflower oils.     

Beiträge zum Reaktionsverhalten der Oxo-alkan-phosphonsäuredialkylester

Contributions towards the Reaction Behaviour of Dialkyl Oxo-alkane-phosphonates Dialkyl oxo-alkane-phosphonates react with dioles and their thio-analogues forming ketales and thioketales 1–19 of the general formula The arylhydrazones prepared from substituted diethyl oxo-alkane-phosphonates and aromatic diazonium salts can be cyclized without preliminar isolation to give the diethyl indolyl-2-phosphonates 20 . 1-Arylidene-2-oxo-propane phosphonic acid esters 22 and 23 react with ethyl β-aminocrotonate through MICHAEL addition followed by enamine formation to yield alkyl dihydropyridine-3-phosphonates 24 and 25 . I. R. data of the compounds prepared are recorded.     

Beiträge zur Analytik von Estersulfonaten

Contributions to the Analysis of Sulfonated Esters Several methods for the characterization and determination of α-Sulfo fatty acid methyl esters are described. The sulfonated ester is detected by thin layer chromatography on silica gel plates with tetrahydrofuran + acetone (1+9 v/v) as solvent and with pinacryptol yellow/UV-light for the visualization. Pyrolysis-gas liquid chromatogrphy with heating a sample/P₂O₅-mixture at 400°C yields the chain length distribution of the fatty acids initially used. The amount of an α-sulfo fatty acid ester is determined by extraction with i-propanol and by two-phase titration (Epton). the saponification product of the sulfonated ester is in the i-propanol insoluble part. For a quantitative determination of the α-sulfo fatty acid methyl ester by thin layer chromatography the sample solution is directly applied to the thin layer plate. A range of defined volumes, with increasing amounts of the sample are applied to the plate by means of an applicator. The chromatograms are visually compared. Ion chromatogrphy with the mobile phase, NH₃/Acetonitrile separates the α-sulfo fatty acid esters by chain-length. Determination is achieved by standards with defined chain-length.     

Beiträge zur Synthese von Orthocarbonsäureamiden

The formamidinium salts 11a, c as well as the nitrile 12 react with sodiumhydride/dimethylamine in the presence of trimethylborate to give the ortho formic acid amide 3a . The orthoamides 6a and 16 can be prepared from the iminium salts 15 and 14 , resp. by the same procedure. Treatment of the azavinylogous formamidinium salt 15 with sodiumhydride and piperidine or morpholine in the presence of trime‐thylborate affords the orthoamides 6c and 6d , resp. By transamination of the azavinylogous aminalester 5a are accessible the orthoamides 6b—d . The vinylogous orthocarbonic acid derivative 17 can be obtained from the salt 14 and sodium alcoholates. The action of sodiumhydride, dimethylamine and trimethylborate on the iminium salt 18 produces a mixture of the orthocarbonic acid derivatives 7a, 8a, 9a . When the guanidinium salt 20 is treated with the same reagents the ortho‐amides 3a and 10a are obtained. The reduction of the salt 20 with sodiumhydride in the presence of several activating reagents (e.g. tetrabutyl orthotitanate, aluminiumisopropylate, trimethylborate) affords the orthoamide 3a . The reduction of the iminium salts 18 and 24 does not proceed clean, giving mixtures of various orthoformic acid derivatives. The form‐amidine 25 can be prepared by reduction of the salt 15 with sodiumhydride/trimethylborate with good yields. By the action of the corresponding carbanions on the guanidinium salt 20 can be obtained the carboxylic acid orthoamides 26—33 . By the same procedure the orthoamides of alkyne carboxylic acids 36a—h, j—n are accessible.     

Beiträge zum reaktiven Verhalten von Sulfinsäurederivaten. VI [1]. Zur α-Aminomethylierung von N-Cyclohexylsulfinamiden

Contributions towards the Reactivity of Derivatives of Sulfinic Acids. Vi. The α-Aminomethylation of N-Cyclohexylsulfinamides N-Cyclohexyl-N-aminomethylsulfinamides are prepared under the conditions of a MANNICH reaction from N-cyclohexyl-N-p-toluene-, -p-chlorobenzene-, -p-bromobenzene- and -methyl-sulfinamides with formaldehyde and secondary amines or O,N-acetals, respectively. The resulting N-amino-methylsulfinamides have been characterized by i.r.-, ¹H-n.m.r.-spectra as well as by some reactions with electrophilic or nucleophilic compounds.     

Beiträge zur galvanisierung von polymeren, 7. Metallisierung von epoxidharzen mit hilfe von haftvermittlern

Epoxy resins can be coated with a metal after being covered with a platable adhesive. Such an adhesive consists of a partly epoxidized styrene-butadiene-styrene block copolymer, an epoxy prepolymer and an amine curer. The contents of these substances in the mixture and the nature of the amine influence the peel strength of the metal layer. The maximum peel strength with a value of about 45 N/25 mm was obtained after using a low molecular weight amine, while values of only about 10 N/25 mm could be obtained with amines of higher molecular weight.