Gas-chromatographische Untersuchung von Naturwachsen

Gas Chromatographic Investigation of Natural Waxes A rapid gas chromatographic method for the identification of natural Waxes is described, according to which the wax acids and the unsaponifiables are investigated after saponification. The methyl esters of the wax acids as well as the acetates and oxidation products from the unsaponifiables showed a characteristic pattern of distribution amongst the individual natural waxes. In the characterization of natural waxes it is desirable to investigate the methyl esters of the wax acids, because after saponification the wax acids are obtained as a more uniform class of substances than the unsaponifiables.     

Über eine dünnschicht-chromatographische Identifizierung genuiner Naturwachse

Identification of Genuine Natural Waxes by Thin-Layer Chromatography Genuine waxes can be identified distinctly in a reproducible manner by examining certain extracts of these waxes by thin-layer chromatography. Using benzene as mobile phase, the extracts are resolved on Silicagel HF plates into individual components that were not investigated further. Under UV light these components are visible as coloured fluorescent spots, whose number, R_F-values and fluorescent colours are characteristic for the genuine natural waxes.     

Natural montan wax and its raffinates

Natural waxes have been used by mankind since prehistoric times. Many uses of wax are based on the imitation of its natural functions. Waxes in nature primarily serve to provide protective barriers on the surfaces of living organisms. Their functions are also determined by wax characteristics such as adhesion and cohesion, as well as slip and deformation effects. In ancient times, for example, wax seals were used to help preserve food and beverages. Beeswax has remained an important material for manufacturing candles up to the present day. Recent vegetable waxes have been used in industry since the mid‐nineteenth century, for example in care products. Refined and chemically processed montan‐based waxes are quite similar to naturally occurring vegetable ester waxes in their structure and application characteristics. They are similar in their environmental characteristics and are also nontoxic. Crude montan wax itself belongs to the naturally occurring waxes of vegetable origin such as candelilla wax and carnauba wax.     

Umweltverhalten und Toxikologie der Wachse

Environmental Behaviour and Toxicology of Waxes Plant and animal waxes are chemically relatively stable nontoxic substances and are used by humans since ages. In the nature waxes have protective function against environmental influences. This protective action is possible due to great resistance of the waxes towards environment, which also means low biological degradability. Obviously, waxes are undigestible and non-toxic in human and animal organism. Partially synthesized waxes based on montana wax, a plant fossil wax, have a structure similar to natural waxes, and therefore they resemble natural waxes with regard to environmental behaviour and are fully harmless from toxicological viewpoint. Also fully synthetic waxes, such as polyethylene waxes and polyethylene oxide waxes have, according to results obtained so far, no undesirable effects on environment. Waxes have been approved in foods worldwide, obviously due to their favorable toxicological properties.     

The composition of beeswax and other waxes secreted by insects

This review deals, with waxes of members of two quite different groups of insects, the bees and the scale insects, which secrete large amounts of wax. The former use was as a structural material and the latter as a protective material. The compositions of waxes from some of these insects are described and particular attention is paid to the compositions of the unhydrolyzed waxes and to the presence of hydroxy acids. New analyses of beeswax and of wax of a species of bumble bee are reported. The structures of the diesters, hydroxyesters and diols of beeswax are elucidated. The bumble bee wax contains major proportions of saturated and unsaturated hydrocarbons, and of long chain saturated, mono- and diunsaturated esters. The relationship between structure and function of the waxes is discussed. Issued as National Research Council of Canada No. 11260. One of six papers to be published from the Symposium on Natural Waxes, presented at the AOCS Meeting, San Francisco, April 1969.     

Zerkleinerung von Wachsen auf Luftstrahlmühlen sowie Verwendung mikronisierter Wachse in Anstrichmitteln

Grinding of Waxes by Air Jet Mills and the Application of Micronized Waxes in Paintings Micronization of crystalline waxes by air jet mills yields products with a main particle size below 5–10 micron. There are no moving parts in the micronizing chamber of the air jet mill. Diminishing of the particles is obtained by collision and friction in the round grinding chamber. By homogeneous distribution of micronized waxes in coating systems special properties like resistance against scratches, dullness, resistance against metal markings can be obtained for dry films of lacquers. The effect of pulverized waxes is used in manifold application areas of lacquers to improve the surface properties.     

Chemometric Classification of Comb and Cuticular Waxes of the Honeybee Apis Mellifera Carnica

Waxes are important as building material and for the chemical communication of the honeybee Apis mellifera carnica. In this study chemometric tools were established for classifying the different waxes inside the hive. By using gas chromatography in combination with mass spectrometry, components of different types of waxes were analyzed. By considering different substance classes of waxes, discriminant function analyses revealed distinct subtypes of comb waxes and of cuticular waxes. It is shown that the aging of comb wax is in part a spontaneous physicochemical process due to differential volatilities of compound classes with different chain length ranges. On the other hand it is directly influenced by the bees by adding lipolytic enzymes to the comb wax. The data suggest that the varying cuticular wax and comb wax compositions could serve as cues for bees to recognize castes, sexes, or comb age.     

Epichlorhydrin in der Wachssynthese

Epichlorohydrine in the Synthesis of Waxes Waxes that are soluble in usual wax solvents are of interest in special fields of application. It is not possible to prepare clear solutions of appreciable concentration using natural waxes, such as carnauba wax or derivatives of montana wax. Although these waxes are well soluble when hot, however, on cooling they separate out as crystalline or pasty masses. For preparing easily soluble waxes a new path of synthesis was found. Thus, waxes having ether or ester groups which were also easily soluble in the cold were prepared by reacting epichlorohydrine with such compounds, which, apart from having a long hydrocarbon chain also possessed a functional group with one active hydrogen atom.     

Der Einfluß von Wachsen auf die Eigenschaften,insbesondere die Scheuerfestigkeit von Druckfarben

The influence of Waxes on the Properties of Printing Inks The influence of waxes on the properties of printing inks and printed materials is shown with the examples of straight chain and differently branched hydrocarbons. The waxes in finely dispersed state are imbedded in the printing inks like pigments and retain this state in the dried printing ink film. Polyethylene waxes change the rheological behaviour of the printing inks and above all improve the scratch and scrubb resistance of the finished prints. On the basis of measurements carried out with printing inks and printed matter it has been tried to explain the mechanism of the action of polyethylene waxes on the printing inks.     

Über Naturwachse XI: Synthesen und Gas-Chromatographie höherer Cyclohexylparaffine

Natural Waxes XI: Synthesis and Gas Chromatography of Higher Cyclohexyl Paraffins Eight cyclohexyl nonadecanes, 1-cyclopentyl eicosane, and three methyl pentacosanes were prepared by Grignard syntheses to serve as model substances in the investigation of minor components of natural waxes. The retention volumes of the pure substances on three different stationary phases (Apiezon L, SE-30, QF-1) were determined by gas chromatography and their mass and infrared spectra were taken. The effect of the position of substituent on the elution behaviour was studied on a series of cyclohexyl and methyl paraffins. The anomalous behaviour of 2-methyl pentacosan, as reported earlier, was confirmed.     

Quantitative Papier-Chromatographie der Fettsäuren

Systematic Quantitative Analysis of Natural Waxes with the Help of Ion-Exchange, Column and Thin-Layer Chromatography A method was developed for the quantitative separation of natural waxes into substance classes. The hydrocarbons were separated by the adsorption chromatography on silica gel/CS₂ column and the separation of acids from alcohols was achieved on a two-phase ion-exchange column after saponification. The isolation of the individual homologues (C₁₆? C₃₂) from the alcohol and acid mixtures was carried out with the help of reversed phase column chromatography by stepwise increase in temperature and acetic acid concentration.     

Plant waxes

The surface of plants is covered with a complex mixture of lipids, often in crystalline form, called plant waxes. The chemistry, biosynthesis, catabolism and function of plant waxes are reviewed. The most common components are hydrocarbons, wax esters, free fatty alcohols and acids. Ketones, secondary alcohols, diols, aldehydes, terpenes and flavones are also found. The major function of the wax appears to be protection of the organism from water loss and other hazards of the environment. The alkanes are formed from fatty acids either by elongation followed by decarboxylation or by head-to-head condensation between two biochemically dissimilar fatty acids followed by specific decarboxylation of one of them. Fatty acyl-CoA is reduced to the aldehyde which in turn is reduced to the alcohol. The alcohol is then esterified with acyl moieties from acyl-CoA or phospholipids. Plant waxes undergo very little catabolism in plants but animals can degrade them to a limited extent and microorganisms readily degrade them. One of six papers to be published from the Symposium on Natural Waxes, presented at the AOCS Meeting, San Francisco, April 1969.     

Wachse für die Zitrusfruchtbeschichtung

Waxes for Citrus Fruit Coating In the last years waxes basing on polyethylen have got a great importance in the field of citrus fruit coating. The propitious physiological and processing properties of these waxes were supposition for this development. Polyethylen wax coatings effect e. g. a reduction of water vapour permeability and lost of weight, an improvement of gloss, influence on respiration and the internal oxygen and carbondioxide content of the fruit.     

Neuartige emulgierbare Polyäthylenwachse

Novel Emulsifiable Polyethylene Waxes In comparison to naturally occuring waxes and their derivatives, the group of synthetically prepared emulsifiable polyethylene waxes known so far exhibit a relatively small proportion of polar centers in their molecular structure. Using a new process of preparation, products having a high content of hydrophilic groups are obtained. The properties and emulsifying techniques are described. This report also includes the development of a new group of purely non-ionic emulsifiable very hard polymer waxes.     

Untersuchungen vollsynthetischer Kohlenwasserstoff-Wachse

Investigation of Fully Synthetic Hydrocarbon Waxes Methods for the structural investigation of synthetic hydrocarbon waxes of a new series of Ruhrwaxes are reported. Besides the molecular weight distribution, which is determined by fractional extraction of the hydrocarbon waxes with an organic solvent and characterization of the fractions by means of molecular weights, solidification points and refractive indices, properties like ability to form adducts with urea, dilatometric and calorimetric measurements as well as assay of IR spectra serve for elucidating the structure and composition.     

Härtemessung an Wachsen nach verschiedenen Methoden

Hardness Determination of Waxes by Different Methods Hardness determination according to the three methods ball-pressure hardness, cone-flow limit and flow hardness were carried out in chemically different waxes. The results of ball-pressure hardness and cone-flow limit were recorded, to measure time depending effects, too. By ball-pressure hardness furthermore elastic deformations can be measured. A corresponding evaluation procedure is suggested. Elastic effects cannot be measured reasonably by cone-flow limit because of their small dimension. The remaining deformations of ball-pressure hardness and cone-flow limit are largely parallel and are correlated in a high degree. Whereas elastic forces are important for ball-pressure hardness, they are extensively suppressed by the complete destruction of the specimen in the flow hardness. Therefore both methods characterize slightly different application features of waxes. The cone-flow limit is between bail-pressure hardness and flow hardness with respect to its results.     

Analyse von Wachsen und Wachsmischungen mit Hilfe der Dünnschicht-Chromatographie

Analysis of Waxes and Mixtures of Waxes by Thin-Layer Chromatography A few commercial waxes were investigated by thin-layer chromatography. The following mobile phases and temperatures were employed: benzene, benzene + 0.5% acetic acid and benzene + 2% methyl acetate at 45°C; tetrachloroethylene at 80°C and tetrachloroethylene + 0.5% acetic acid at 70°C. A few examples showing the possibility of analyzing wax mixtures with the help of the methods described here, are given.     

Über die Zerlegung von Kohlenwasserstoff-Gemischen mit Hilfe selektiver Extraktionsmethoden × — Zerlegung von Gatschen aus einem paraffinbasischen Rohöl

The Analysis of Hydrocarbon Mixtures with the Help of Selective Extraction Methods × — Analysis of Crude Waxes from a Paraffin Based Crude Oil The analysis of three crude waxes from different fractions of paraffin based crude oil, with the help of solid-liquid extraction and finally by urea-adduct formation, is reported. On the basis of selected physical data and suitable diagrams, the structural composition of the hydrocarbon components of these three crude waxes is discussed.