Specific Properties of Artificial [Buna] Rubber

1937 ◽  
Vol 10 (1) ◽  
pp. 17-28
Author(s):  
Albert Koch
Keyword(s):  
Natural Rubber ◽  
Raw Materials ◽  
Small Extent ◽  
Raw Material ◽  
World War ◽  
Methyl Group ◽  
Synthetic Product ◽  
Laboratory Results ◽  
Short Time ◽  
Resistance To Heat

Abstract Developments in the Synthesis of Rubber Because of the peculiar properties of natural rubber, its usefulness is somewhat limited, and in many fields of application it is quite unsuitable. In contact with oils and fats it swells rapidly and loses almost completely its good mechanical properties, and besides this natural rubber has poor resistance to heat. Again it is attacked rather easily by oxygen, and on exposure to oxygen and light simultaneously there is a particularly strong tendency to develop cracks within a short time; it is for such reasons that the chemical industries of various countries have been looking for an artificial or synthetic product which is free from the shortcomings of natural rubber or exhibits them to only a relatively small extent. Experimentation on artificial rubber has depended fundamentally on the discovery of Harries that the natural rubber molecule is constructed of isoprene units. Isoprene and its allied hydrocarbons were prepared by Hoffmann and his coworkers at the Elberfeld dye works, and these compounds were in turn polymerized to masses similar to rubber. These experiments were carried out before the World War. Because of a shortage of raw materials during the War, it was necessary to adapt the laboratory results to a factory scale sooner than should logically have been done. At that time the most readily available technical raw material was dimethylbutadiene, a compound which differs from isoprene by the presence of an extra methyl group, as may be seen in Table I.

Staining Natural Rubber with Silver Nitrate for Electron Microscopy

1977 ◽  
Vol 50 (4) ◽  
pp. 835-841 ◽  
Author(s):  
R. W. Smith ◽  
V. L. Folt
Keyword(s):  
Electron Microscopy ◽  
World War Ii ◽  
Natural Rubber ◽  
Silver Nitrate ◽  
Raw Materials ◽  
Natural Rubber Latex ◽  
Optical Microscope ◽  
Raw Material ◽  
World War ◽  
The One

Abstract Hevea brasiliensis or natural rubber (NR) has been used for over 500 years. Until World War II, it was the basic raw material of the rubber industry. Since that time, the use of synthetic polymers has steadily increased, but the importance of NR has not diminished. In fact, the future for the natural product is very promising since it is the one polymer that is obtainable without depleting fossil fuel raw materials. Natural rubber latex has been extensively studied by a variety of methods, especially the microscope. All of the early work with NR latex was conducted, of course, with the optical microscope. In the late 1940's the electron microscope began to be used, but at that time synthetic rubbers began to demand attention, and work on NR latex diminished. Perhaps investigators felt they knew all there was to know about the microscopical characteristics of this material. Indeed, some very fine work had been done and keen observations made with optical microscopes that could not even resolve all of the particles in a latex material. This paper deals with the electron microscopy of natural rubber latexes with particular attention to the proteinaceous layer on the particle and the fate of particles during varying stages of mastication. The critical technique used was to stain the proteinaceous layer of the latex particle with silver nitrate.

French Direct Investments in the Ottoman Empire Before World War I

2011 ◽  
Vol 12 (3) ◽  
pp. 525-561 ◽  
Author(s):  
V. Necla Geyikdagi
Keyword(s):  
World War I ◽  
Ottoman Empire ◽  
Direct Investment ◽  
Raw Materials ◽  
Raw Material ◽  
World War ◽  
Foreign Service ◽  
The Balkans ◽  
Service Companies ◽  
Manufactured Products

Foreign direct investment entered into the Ottoman Empire to support and develop foreign trade. Europeans who wanted to sell their manufactured products and acquire raw materials were instrumental in the construction of trade-related infrastructure in this country. Therefore, the first French investments, like those of other countries, were made for constructing railways and ports. The growth of raw material production in primary commodities, finally led to an increase in the number of foreign service companies such as banks and insurance providers that served these transport and production facilities. The initial motivations of French investors were mainly economic as they tried to find new markets and secure a viable share in these markets before their international competitors. Motives gradually became political as the opinion about the disintegration of the Ottoman Empire got stronger by the end of the nineteenth century. The French government assisted its investors in obtaining important concessions for investments in Anatolia, the Balkans, and the Arab provinces of the Empire.

scholarly journals Potentials of Edible Canna (Canna edulis Kerr) Starch for Bioplastic: A Review

2021 ◽  
Vol 10 (2) ◽  
pp. 182-191
Author(s):  
Azmi Alvian Gabriel ◽  
◽  
Anggita Fitri Solikhah ◽  
Alifia Yuanika Rahmawati ◽  
Yunita Sasmi Taradipa ◽  
...  
Keyword(s):  
Mineral Content ◽  
Raw Materials ◽  
Amylose Content ◽  
Experimental Studies ◽  
Raw Material ◽  
Carbohydrate Source ◽  
Polybutylene Succinate ◽  
Treatment Use ◽  
High Amylose ◽  
Short Time

Starch-based bioplastic was more economical and competitive compared to bacteria-based bioplastics (polylactic acid, polybutylene succinate, and polyhydroxyalkanoates) due to the starch variances and the availability in Indonesia, along with the simple techniques that can be applied. This review aimed to describe the potential and opportunities of edible canna starch as an alternative raw material of bioplastics production. Edible canna tuber productivity in Java, Indonesia, with a harvest age of about eight months reaches 30-49.4 tons/ha. It will produce a mature segment 70.2% of the total harvest weight. Edible canna tuber was a carbohydrate source that contains 88.10% starch with an advantage of 68% higher fiber and mineral content than other tubers. Furthermore, canna tuber starch contains amylose proportions of 35.0%. The high amylose content in canna starch is one of the properties that can position its function for developing packaging materials. The gelatinization process of canna starch requires a short time and low energy because of its large granule size (56 μm). A literature review of canna starch as an alternative of bioplastic raw materials needs to be carried out to obtain accurate data and information regarding treatment, use of additional materials, and characteristics of bioplastic products resulting from experimental studies so that they can be further implemented.

scholarly journals Efficient use of microwave EMF and multilevel high temperature sterilization modes in apple puree technology for dietetic nutrition

2020 ◽  
Vol 222 ◽  
pp. 03005
Author(s):  
M.M. Rakhmanova ◽  
A.F. Demirova ◽  
M.E. Akhmedov ◽  
Z.A. Abdulkhalikov ◽  
T.N. Daudova
Keyword(s):  
Heat Treatment ◽  
High Temperature ◽  
Raw Materials ◽  
Nutrient Composition ◽  
Raw Material ◽  
Saturated Steam ◽  
Technical Data ◽  
Short Time ◽  
Apple Puree ◽  
Apple Purée

The article is dedicated to improving the quality of apple puree with xylitol for dietetic nutrition due to the development and implementation of a new technological process. This is microwave boiling of apples, rather than traditional steaming using saturated steam before chopping, with the development of a device for its implementation and multilevel high-temperature sterilization modes with prebake of apple puree in glass jars in microwave EMF. The analysis of research and technical data proved that pre-heat treatment of apples with saturated steam and traditional sterilization modes have a considerable duration, which impairs the finished products quality and has an adverse effect on the nutrient composition of the raw material during processing. Substituting the traditional method of pre-heat treatment of apples for their short-time processing in microwave EMF reduces the process by more than twice, which, in turn, contributes to an increased preservation of the nutrient composition of apples, while enhancing the yield of apple puree. For the implementation of microwave processing method of raw materials, a new design of the device for electromagnetic treatment of plant roughage has been developed, providing a uniform and more intensive heat treatment of raw materials in a continuous flow. Rapid multilevel high-temperature sterilization modes with the application of apple puree in glass jars in microwave EMF, liquid high-temperature heat devices and an autoclave basket, providing the opportunity for thermal sterilization of the product without creating reverse pressure in the machine, generally contribute to reducing heat costs and increasing the nutritional value.

KINETICS OF DEHUMIDIFICATION АND DESTRUCTION OF VITAMIN C CONTENT DURING INFRARED DRYING OF FRUIT AND BERRIES IN A MULTI-TIERED DRIER U

2020 ◽  
pp. 56-63
Author(s):  
ALEKSEI A. ZAVALIY ALEKSEI A. ◽  
◽  
LYUDMILA A. LAGO LYUDMILA A. ◽  
ALEKSANDR S. RYBALKO ALEKSANDR S.
Keyword(s):  
Vitamin C ◽  
Raw Materials ◽  
Heat Exposure ◽  
Analytical Description ◽  
Raw Material ◽  
Material Surface ◽  
Plant Materials ◽  
Coeffi Cients ◽  
Short Time ◽  
The Relationship

The fi rst-order model of chemical kinetics was applied for an analytical description of the destruction of vitamin C content during the infrared (IR) drying of plant materials. In this model, the authors used the Arrhenius equation to describe the temperature infl uence on the speed of the simulated processes. The coeffi cients of the model were determined by the xperimental data for IR drying of raspberries and sliced apples. The authors found the relationship between the temperature of raw materials, the time of heat exposure and destruction of vitamin C in fruit and berries during IR drying. The study determined the requirements for maximum preservation of the native properties of raw materials during their drying in a multilevel drying machine. They include minimizing the contact of the raw material surface with an oxidizing environment; carrying out drying at a minimum temperature irregularity of raw materials and over a short time at the maximum permissible temperatures of raw materials under atmospheric pressure in the drier unit.

scholarly journals TO THE QUESTION OF JUSTIFICATION OF RATIONAL CONDITIONS OF WAX RAW MATERIAL PURIFICATION IN WATER WITH INTENSIVE MECHANICAL MIXING

2020 ◽  
Author(s):  
Д.Е. Каширин ◽  
И.А. Успенский ◽  
В.В. Павлов ◽  
И.А. Юхин ◽  
А.А. Петухов
Keyword(s):  
Raw Materials ◽  
Heat Exposure ◽  
Bound State ◽  
Physical Principle ◽  
Water Soluble ◽  
Raw Material ◽  
Mechanical Mixing ◽  
Mechanical Stirring ◽  
Organic Impurities ◽  
Short Time

лавной технологической операцией при производстве пасечного воска является его термическое выделение из воскового сырья различной сортности с применением сухого или влажного способа вытопки, реализуемого посредством воскотопок всевозможных типов и конструкций. Так как в основу процесса вытопки положен физический принцип стекания расплавленного воска, сырье подвергается обязательному тепловому воздействию с переходом содержащегося в нем свободного воска в жидкое состояние. Сортность воскового сырья непосредственно связана с его восковитостью – массовой долей воска и зависит от количества и состава содержащихся в нем загрязнений. Расплавленный воск взаимодейсвтует с загрязняющими примесями, впитывается в них, переходя в связанное состояние, при этом выход свободно стекаемого воска уменьшается. В основу предлагаемого способа очистки воскового сырья от перги и других водорастворимых примесей положено удаление загрязнений из предварительно измельченных сотов до их горячей переработки путем погружения загрязненного вороха в емкость с водой и интенсивного механического перемешивания в течение непродолжительного времени, в результате чего органические примеси диспергируются или переходят в раствор, и появляется возможность отделить их от очищенных восковых частиц путем процеживания. Целью данного исследования является установление зависимости количества удаленных загрязнений из воскового сырья в результате его очистки в воде при механическом перемешивании лопастной мешалкой с электроприводом от интенсивности процесса перемешивания и его продолжительности. В результате проведенного исследования получена регрессионная модель процесса и проведена оптимизация с установлением максимального значения критерия и соответствущих ему значений исследуемых факторов. The main technological operation in the production of apiary wax is its thermal separation from wax raw materials of various grades using a dry or wet refining method, realized through wax reflows of various types and designs. Since the basis of the flooding process is the physical principle of runoff of molten wax, the raw material is subjected to mandatory heat exposure with the transition of the free wax contained in it into a liquid state. The grade of the wax raw material is directly related to its waxiness - the mass fraction of wax and depends on the amount and composition of the impurities contained in it. The molten wax interacts with contaminants, is absorbed into them, passing into a bound state, while the yield of freely draining wax decreases. The basis of the proposed method for cleaning wax raw materials from bee bread and other water-soluble impurities is the removal of contaminants from pre-ground honeycombs before hot processing by immersing the contaminated heap in a container with water and intensive mechanical stirring for a short time, as a result of which organic impurities are dispersed or transferred to solution, and it becomes possible to separate them from the purified wax particles by filtering. The aim of this study is to establish the dependence of the number of removed contaminants from wax raw materials as a result of their purification in water with mechanical stirring with a paddle mixer with an electric drive on the intensity of the mixing process and its duration. As a result of the study, a regression model of the process was obtained and optimization was carried out with the establishment of the maximum value of the criterion and the corresponding values ​​of the studied factors.

Semiebonites

1949 ◽  
Vol 22 (1) ◽  
pp. 186-200
Author(s):  
Fritz S. Rostler
Keyword(s):  
Natural Rubber ◽  
Construction Industry ◽  
Large Volume ◽  
Raw Materials ◽  
Unsaturated Hydrocarbon ◽  
Raw Material ◽  
Phenolic Resins ◽  
Rubber Industry ◽  
Combined Use ◽  
Butadiene Styrene

Abstract To summarize the principal results of the present investigation, it was found that whereas natural rubber is a poor raw material for the manufacture of semiebonite, butadiene-styrene and butadiene-acrylonitrile rubbers are suitable raw materials, especially in combination with unsaturated hydrocarbon extenders of the Naftolen type. The superiority of GR-S to natural rubber in the form of semiebonite should be an interesting piece of information for every compounder conscientious about the importance of keeping up the use and the manufacture of GR-S. With natural rubber becoming more and more available, there exists, as we all know, the definite danger that GR-S will be pushed into the background. As a matter of fact, we are approaching the situation where the supply of rubber hydrocarbons, natural and synthetic, will exceed the demand by multiples if new uses for rubber in large volume are not found. The increased use of rubber products in the building and construction industry and in road surfacing might provide such an outlet for rubber. Semiebonite with good aging qualities might find many uses along these lines. It might lend itself to the manufacture of floor coverings, of waterproof wall insulation, etc. The possibilities of using semiebonites from GR-S for tire beads has been suggested in a previously published article, but no detailed study comparing various rubbers has been reported. The primary purpose of this report is to present these basic data, which can be used as starting points for compound development and to point out that we have in the semiebonite range a possibility of using GR-S to advantage. As to butadiene-acrylonitrile rubbers, with which, in distinction to GR-S, very useful semihard rubber products can be made with phenolic resins, the medium sulfur range opens the possibility of making semiebonites which are easier to process and cheaper than resin combinations. The use of plastics in the rubber industry was recently discussed and summarized by Winkelmann. The compounding of semiebonites with Naftolen-type products offers a means of regulating the plasticity of the uncured stock as well as the elongation of the vulcanizate. Aging and prevention of sulfur bloom appear also improved. In other words, it was found that the combined use of 15 to 20 parts of sulfur with 15 to 50 parts of a Naftolen-type hydrocarbon gives a satisfactory semiebonite with GR-S, as well as with Hycar, and both these rubbers appear superior to natural rubber in semiebonites.

scholarly journals Ozonation as a Method of Abiotic Elicitation Improving the Health-Promoting Properties of Plant Products—A Review

Molecules ◽  
2020 ◽  
Vol 25 (10) ◽  
pp. 2416 ◽  
Author(s):  
Monika Sachadyn-Król ◽  
Sofia Agriopoulou
Keyword(s):  
Raw Materials ◽  
Primary Objective ◽  
Raw Material ◽  
Ozone Treatment ◽  
High Concentration ◽  
Plant Products ◽  
Plant Raw Materials ◽  
Health Promoting ◽  
Short Time

In this review, the primary objective was to systematize knowledge about the possibility of improving the health-promoting properties of raw plant products, defined as an increase in the content of bioactive compounds, by using ozone. The greatest attention has been paid to the postharvest treatment of plant raw materials with ozone because of its widespread use. The effect of this treatment on the health-promoting properties depends on the following different factors: type and variety of the fruit or vegetable, form and method of ozone treatment, and dosage of ozone. It seems that ozone applied in the form of ozonated water works more gently than in gaseous form. Relatively high concentration and long contact time used simultaneously might result in increased oxidative stress which leads to the degradation of quality. The majority of the literature demonstrates the degradation of vitamin C and deterioration of color after treatment with ozone. Unfortunately, it is not clear if ozone can be used as an elicitor to improve the quality of the raw material. Most sources prove that the best results in increasing the content of bioactive components can be obtained by applying ozone at a relatively low concentration for a short time immediately after harvest.

scholarly journals REALIZATION OF IMPORT SUBSTITUTION POLICY IN THE RUSSIAN FEDERATION (ON THE EXAMPLE OF THE DAIRY INDUSTRY OF THE REPUBLIC OF TATARSTAN)

2018 ◽  
Vol 13 (2) ◽  
pp. 151-154 ◽  
Author(s):  
Ольга Кириллова ◽  
Olga Kirillova
Keyword(s):  
Russian Federation ◽  
Raw Materials ◽  
Import Substitution ◽  
Raw Material ◽  
Investment Activity ◽  
Insufficient Amount ◽  
The Russian Federation ◽  
The Republic ◽  
Short Time ◽  
Near Future

The problems of import substitution in Russia arose long ago, even before the introduction of anti-Russian sanctions and counter-sanctions. This is due to the fact, that Russia is an exporting country of raw materials, which led to import dependence on other countries. At present, there is an urgent need to introduce import substitution policies, insufficient amount of equipment and means of production, raw material and its sources, lack of effective infrastructure does not allow Russia to fully provide itself with the necessary food products. It is also important that, for example, there are foreign competitors in the dairy market, who sell their products much cheaper than Russian ones. A good example is Belarus. Recently, Armenia has become an active participant in the market, which exports cheese to Russia. But after all, as you know, if it’s cheaper, then the quality suffers. The volume of falsified products also increases. According to experts, Russian producers will not be able to satisfy the needs of the population in the near future, because it is necessary to increase the milch herd, significantly improve the village infrastructure, purchase the necessary equipment, etc. The volume of investments in this sector should be 200-500 billion rubles. This can not be done in a short time and therefore Russia will still depend on imports of dairy products from Belarus and other countries. Therefore, the Russian Federation needs to take the necessary measures that will enable the state to protect not only dairy, but also other branches of agriculture in Russia, which will immediately affect the quality and income of the country’s population. Fully apply import substitution in Russia will be unprofitable for the economy and will be associated with increased inflation, a decrease in savings, a reduction in investment activity, a deficit in the balance of payments.

scholarly journals Selection of Tanned-Leather Waste in Recovering Novel Raw Material for Manufacturing Rubber Artifacts: Towards a Zero-Waste Condition

2020 ◽  
Vol 10 (15) ◽  
pp. 5374
Author(s):  
Gennaro Bufalo ◽  
Bruno Molino ◽  
Luigi Ambrosone
Keyword(s):  
Natural Rubber ◽  
Solid Waste ◽  
Raw Materials ◽  
Three Dimensional ◽  
Resource Recovery ◽  
Raw Material ◽  
Zero Waste ◽  
Leather Waste ◽  
Chemical Pretreatments ◽  
Mechanical Performances

Zero-waste is an ambitious goal to encourage sustainable production, consumption optimum recycling and resource recovery. The recycling and resource recovery of chrome-tanned leather waste is a difficult proposition because of the three-dimensional chemical network of collagen, which renders leather waste incompatible to polymer matrices. Many attempts have been undertaken to reuse leather waste, most of them require technological processes and challenging chemical pretreatments, which make the reuse an economically disadvantageous industrial operation. The paper aims to show how a very fine separation of leather solid waste leads to raw materials suitable for mixtures with natural rubber, without any chemical pretreatment. In other words, the paper intends to be a stimulus to manage leather solid waste carefully to start a cleaner and more profitable production. In particular, various industrial compounds containing different concentrations of post-tanning dyeing, or chrome shaving or oil-tanning and natural rubber were vulcanized through a standard preparation. Some compounds were also reinforced with carbon black and the vulcanization kinetics were monitored through rheometer. Experimental results indicate that there exists an optimal concentration of waste such that post-tanning dyeing post-tanning and chrome shaving are suitable for manufacture floor mats, soles and heels while oil-tanning waste can be used for making hose or conveyor belts. The mechanical performances of the articles prepared by direct mixing with leather waste are the same as those of commercially distributed rubber products.

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