The Measurement of Water Absorption by Rubber

1933 ◽  
Vol 6 (1) ◽  
pp. 24-32
Author(s):  
H. A. Daynes
Keyword(s):  
Water Absorption ◽  
Moisture Absorption ◽  
Recent Literature ◽  
Hot Water ◽  
Raw Material ◽  
Insulating Materials ◽  
Vulcanized Rubber ◽  
Rate Of Absorption ◽  
The Subject ◽  
Selection Of

Abstract The absorption of water by rubber has occupied a prominent place in recent literature, especially in connection with cable and other insulating materials, since it is well known that their electrical properties are adversely affected by absorbed moisture. Many other classes of rubber goods and materials also are subject to water absorption, e. g., rubber soling, tires, washers, packings, hose, tank and grinding mill linings, hot-water bottles, and surgical goods. Apart from the performance, of such articles in service, moisture absorption is important in relation to factory operations, such as drying and vulcanizing, and to storage and mechanical testing. This paper deals with the selection of a method for measuring the amount of water absorbed by rubber when saturation has been reached. In the work for which the method was developed, the rate of absorption was of no interest; but it was necessary to correlate the water absorbed by the vulcanized product with that absorbed by the raw material, so that a method was required which could be applied equally well to raw rubber, vulcanized rubber, and ebonite. It is not proposed to discuss in detail the mechanism of absorption. The literature has already been briefly reviewed by Lowry and Kohman (J. Phys. Chem., 31, 23 (1927)), who have been largely responsible for present ideas on the subject. It will be sufficient to recall that the process is a reversible one, and that the amount absorbed at any temperature depends on the humidity of the surrounding gas and the nature of the rubber.

scholarly journals Foam Polymers in Multifunctional Insulating Coatings

Polymers ◽  
2021 ◽  
Vol 13 (21) ◽  
pp. 3698
Author(s):  
Ter-Zakaryan K. A. ◽  
Zhukov A. D. ◽  
Bobrova E. Yu. ◽  
Bessonov I. V. ◽  
Mednikova E. A.
Keyword(s):  
Thermal Conductivity ◽  
Water Absorption ◽  
Moisture Absorption ◽  
Water Immersion ◽  
Average Density ◽  
Operating Conditions ◽  
Insulating Materials ◽  
Longitudinal Tensile Strength ◽  
Metallized Coating ◽  
Outer Perimeter

The application of foamed polymers as one of the components of insulating coatings allows to solve the problems of energy saving and creation of optimal operating conditions for constructions. The systems of application of energy-efficient heat-insulating materials must consider both the particularities of the insulating materials and the functional orientation of the constructions. The implementation of the concept of seamless insulating coatings implies the achievement of thermal effect and reduction in air permeability both by means of the application of thermal insulation with low thermal conductivity and the minimization of junctions between separate elements of the insulating coating, which is achieved using elastic foamed polymers and, first of all, polyethylene foam. Construction of seamless insulating coatings creates practically impermeable heat, vapor, and water barriers along the outer perimeter of the insulated object. Multilayer products based on polyethylene foam represent a relatively new material—a fact that requires examination of their properties, as well as under various operating conditions, and development of a methodology for evaluation of the operational resistance of these materials in structures of different purposes, including cold conservation. The performed tests have shown that the compressive strength at 10% deformation is determined by the function of load application area and varies from 70 kPa during the test of cube samples of 10 × 10 × 10 in size to 260 kPa for areas exceeding 100 m2. The longitudinal tensile strength amounts to 80–92 kPa, and the strength of the weld seam is equal to 29–32 kPa. It has been established that the values of thermal conductivity of polyethylene foam with an average density of 18–20 kg/m3 amounts to 0.032–0.034 W/(m·K), diffusion moisture absorption is equal to 0.44 kg/m2 without a metallized coating and 0.37 kg/m2 with a metallized coating; water absorption after partial immersion in water for 24 h amounts to 0.013 kg/m2; water absorption by volume after complete water immersion for 28 days is equal to 0.96%. The material does not practically change its properties under conditions of long-term temperature alteration from −60 to +70 °C. The developed and implemented insulation systems for protective surfaces of framed construction objects, rubbhalls and frameless structures, floating floors, indoor ice rinks, and snow conservation systems are presented.

Water Absorption and Thickness Swelling of Laminated Composite after Cured at Different Angle

2013 ◽  
Vol 465-466 ◽  
pp. 86-90 ◽  
Author(s):  
Mohd Yuhazri bin Yaakob ◽  
T.T.T. Jennise ◽  
H. Sihombing ◽  
N. Mohamad ◽  
S.H. Yahaya ◽  
...  
Keyword(s):  
Water Absorption ◽  
Composite Structures ◽  
Moisture Absorption ◽  
Glass Fibers ◽  
Laminated Composite ◽  
High Water ◽  
Raw Material ◽  
Thickness Swelling ◽  
Gravity Effects ◽  
Materials Used

Moisture absorption is a very important factor in polymers and composite materials used for hull manufacture and stability in marine environment. High water absorption of the material will affects the mechanical properties and stability in composite. This research is carried out to study the feasibility of the gravity effects on curing position of the laminated composite structures to enhance the curing space needed. Vertical cured laminate having almost similar properties with common horizontal cured laminate able to save much space in composite industry. Horizontal cured laminates filled up spaces in which SMI lack of. Polyesters and E-glass fibers were used as the raw material in this research. Vacuum bagging technique was used to suck out the excess resin during lay-up to avoid any voids and air inside laminate and cured at different angle position in room temperature for 24 hours. Seven samples of laminated composite were fabricated and cut into specific dimension in accordance to ASTM standard. This paper will discuss about the investigation on the water absorption and thickness swelling of the thermosetting laminated composite by curing the laminate at different angle using vacuum bagging technique. From the testing, SN6 and SN7 shows to have good water resistant in physical properties.

Deproteinized Rubber

1937 ◽  
Vol 10 (2) ◽  
pp. 288-298
Author(s):  
C. R. Boggs ◽  
J. T. Blake
Keyword(s):  
Water Absorption ◽  
Far East ◽  
Dielectric Strength ◽  
Raw Material ◽  
Operating Voltage ◽  
Electrical Stability ◽  
Vulcanized Rubber ◽  
Rubber Compounds ◽  
Electrical Engineers ◽  
Cable Company

Abstract FOR some years deproteinized rubber has been used by this company in the manufacture of rubber insulation, and the rate of consumption is increasing rapidly. This new and unique raw material is now also being manufactured for the Simplex Wire and Cable Company by The Goodyear Tire and Rubber Company on plantations in the Far East. The special virtue of deproteinized rubber is its low water absorption and the electrical stability which it imparts to vulcanized rubber compounds immersed in water. Electrical engineers are specifying such compounds for submarine, underground, and duct cables and all other insulation that may be exposed to water. The electrical properties of ordinary rubber insulation are impaired by increasing water absorption; the dielectric strength decreases, and the capacitance and leakance (or dielectric loss) increase. Power cables become useless when decreasing dielectric strength is insufficient to withstand operating voltage. Communication cables deteriorate rapidly by water absorption because their increasing capacitance and leakance prevent the practical transmission of signals long before dielectric strength is low enough to cause failure at the extremely low operating voltage of such cables.

scholarly journals Amaranth bran powder is a promising raw material for the confectionery industry

2021 ◽  
Vol 262 ◽  
pp. 01005
Author(s):  
Svetlana Khasanova ◽  
Zinaida Skobelskaya
Keyword(s):  
Moisture Absorption ◽  
New Technology ◽  
Waste Product ◽  
Dry Weight ◽  
Water Soluble ◽  
Raw Material ◽  
Relative Air Humidity ◽  
Confectionery Products ◽  
Human Need ◽  
Selection Of

The research is devoted to the creation of a new raw material - a product of processing amaranth seeds of the species Amaranthus L. (variety “Krepysh”, selection of FNTSO). Developed amaranth bran powder, which is a waste product in the production of oil from seeds. The bran contains 19.6% proteins, including water-soluble ones; 17.9% dietary fiber; 46.9% highly dextrinated starch; 1.01% of macro- and microelements, including deficient selenium. The selenium content in the studied batches of amaranth bran is 0.053 mg% per 100 g of dry weight, which allows us to meet the average daily human need for selenium by 70%. The new technology includes infrared processing, bran cooling and fine grinding. Infrared processing allows targeted action on protein and carbohydrate complexes, increasing the biological value of amaranth bran powder, imparting increased moisture absorption properties to the product, and maintaining high quality indicators. Amaranth bran powder was stored at a temperature of 18 ± 2⁰С, relative air humidity 75 ± 1⁰С, in the presence of photocatalytic air purifiers “Tiokraft M-400”. A new product - amaranth bran powder is recommended for use in the production of sugar and flour confectionery products

Materials for Electron Beam Information Storage

1969 ◽  
Vol 27 ◽  
pp. 152-153 ◽  
Author(s):  
D. E. Speliotis
Keyword(s):  
Magnetic Field ◽  
Electron Beam ◽  
Recent Literature ◽  
Electron Beams ◽  
Information Storage ◽  
The Subject ◽  
The Magnetic Field

The interaction of electron beams with a large variety of materials for information storage has been the subject of numerous proposals and studies in the recent literature. The materials range from photographic to thermoplastic and magnetic, and the interactions with the electron beam for writing and reading the information utilize the energy, or the current, or even the magnetic field associated with the electron beam.

Thomas More’s Correspondence in a Spanish Ambiance

Moreana ◽  
2002 ◽  
Vol 39 (Number 149) (1) ◽  
pp. 41-60 ◽  
Author(s):  
Eugenio M. Olivares Merino
Keyword(s):  
The Subject ◽  
Selection Of

The recent reprinting of Álvaro de Silva’s 1998 edition of a selection of More’s letters prompts the author to examine the subject of Spanish translations of More, and of de Silva’s general commentary on More’s correspondence and on his relationship to other humanists. The author reflects on aspects of More’s personality as exposed in his letters and uses what he finds as a corrective to several biographical misconceptions. He points out the strengths and weaknesses of de Silva’s work and compares it with that of other translators, particularly Elizabeth Rogers, and notes the particularly Spanish quality of de Silva’s edition.

Teknologi Esktrasi dan Cara Pemisahannya untuk Mendapatkan Kembali Karotenoid dari Minyak Sawit : Suatu Tinjauan

2016 ◽  
Vol 9 (1) ◽  
pp. 80-95
Author(s):  
Agus Sudibyo ◽  
Sardjono Sardjono
Keyword(s):  
Vitamin A ◽  
Palm Oil ◽  
Beta Carotene ◽  
Cost Effective ◽  
Raw Material ◽  
Extraction And Separation ◽  
Molecular Product ◽  
Industrial Use ◽  
Palm Oil Mill ◽  
Selection Of

Crude palm oil (CPO)is the richest natural plant source of carotenoids in terms of retinol (pro-vitamin A) equivalent, whereas palm oil mill effluent (POME) is generated from palm oil industry that contains oil and carotenes that used to be treated before discharge. Carotenoids are importance in animals and humans for the purpose of the enhancement of immune response, conversion of vitamin A and scavenging of oxygen radicals. This component has different nutritional  functions and benefits to humaan health. The growing interest in the other natural sources of beta-carotene and growing awareness to prevent pollution has stimulated the industrial use of CPO and POME as a raw material for carotenoids extraction. Various technologies of extraction and separation have been developed in order to recover of carotenoids.This article reports on various technologies that have been developed in order to recover of carotenoids from being destroyed in commercial refining of palm oil and effects of some various treatments on the extraction end separation for carotenoid from palm oil and carotenoids concentration. Principally, there are different technologies, and there is one some future which is the use of solvent. Solvent plays important role  in the most technologiest, however the problem of solvents which are used is that they posses potentiaal fire health and environmental hazards. Hence selection of the  most safe, environmentally friendly and cost effective solvent is important to design of alternative extraction methods.Chemical molecular product design is one of the methods that are becoming more popular nowadays for finding solvent with the desired properties prior to experimental testing.ABSTRAKMinyak sawit kasar merupakan sumber karotenoid terkaya yang berasal dari tanaman sawit sebagai senyawa yang sama dengan retinol atau pro-vitamin A; sedangkan limbah pengolahan minyak sawit dihasilkan dari industri pengolahan minyak sawit yang berisi minyak dan karotene yang perlu diberi perlakuan terlebih dahulu sebelum dibuang. Karotenoid merupakan bahan penting yang diperlukan pada hewan dan manusia guna memperkuat tanggapan terhadap kekebalan, konversi ke vitamin A dan penangkapan gugus oksigen radikal. Dengan berkembangnya ketertarikan dalam mencari beta-karotene yang bersumber dari alam lain dan meningkatnya kesadaran untuk mencegah adanya pencemaran lingkungan, maka mendorong suatu industri untuk menggunakan CPO dan POME sebagai bahan baku untuk diekstrak karotenoidnya. Berbagai macam teknologi guna mengekstrak dan memisahkan karotenoid telah dikembangkan untuk mendapatkan kembali karotenoidnya. Makalah ini melaporkan dan membahas berbagai jenis teknologi yang telah dikembangkan guna mendapatkan kembali senyawa karotenoid dari kerusakan di dalam proses pemurnian minyak sawit secara komersial dan pengaruh beberapa perlakuan terhadap ekstrasi dan pemisahan karotenoid dari minyak sawit dan konsentrasi karotenoidnya. Pada prinsipnya, berbagai teknologi yang digunakan untuk mengekstrak dan memisahkan karotenoid terdapat perbedaan, dan terdapat salah satu teknologi yang digunakan untuk esktrasi dan pemisahan karotenoid adalah menggunakan bahan pelarut. Pelarut yang digunakan mempunyai peranan yang penting dalam teknologi ekstrasi; namun pelarut yang digunakan untuk mengekstrak tersebut mempunyai persoalan karena berpotensi mengganggu kesehatan dan membahayakan cemaran lingkungan. Oleh karena itu, pemilihan jenis teknologi yang aman, ramah terhadap lingkungan dan biaya yang efektif untuk penggunaan pelarut merupakan hal penting sebelum dilakukan desain metode/teknologi alternatif untuk esktrasi karotenoid. Pola produk molekuler kimia merupakan salah satu metode yang saat ini menjadi lebih populer untuk mencari pelarut dengan sifat-sifat yang dikehendaki sebelum diujicobakan. Kata kunci :    karotenoid, ekstrasi, pemisahan, teknologi, minyak sawit kasar, limbah industri pengolahan sawit.

Tanks in the Spa Town. The New Book about the Events of the Year 1968 in Czechoslovakia

2019 ◽  
Vol 14 (1-2) ◽  
pp. 278-282
Author(s):  
Kirill A. Popov
Keyword(s):  
Fiftieth Anniversary ◽  
Warsaw Pact ◽  
Scientific Event ◽  
The Social ◽  
Prague Spring ◽  
The Subject ◽  
Scientific Terms ◽  
Selection Of ◽  
Regional Perspective ◽  
The Way

This review is devoted to the monograph by Jan Nedvěd “We do not decline our heads. The events of the year 1968 in Karlovy Vary”. The Karlovy Vary municipal museum coincided its publishing with the fiftieth anniversary of the Prague spring which, considering the way of the presentation, turned the book not only to scientific event but also to the social one. The book describes sociopolitical trends in the region before the year 1968, the development of the reformist movement, the invasion and advance of the armies of the Warsaw Pact countries, and finally the decline of the reformist mood and the beginning of the normalization. Working on his writing, the author deeply studied the materials of the local archive and gathered the unique selection of the photographs depicting the passage of the soviet army through the spa town and the protest actions of its inhabitants. In the meantime, Nedvěd takes undue freedom with scientific terms, and his selection of historiography raises questions. The author bases his research on the Czech papers and scarcely uses the books of Russian origin. He also did not study the subject of the participating of the GDR’s army in the operation Danube, although these troops were concentrated on the borders of Karlovy Vary region as well. Because of this decision, there are no materials from German archives or historiography in the monograph. In general, the work lacks the width of studying its subject, but it definitively accomplishes the task of depicting the Prague spring from the regional perspective.

scholarly journals Selection of plantain cultivars as raw material for ripe plantain flour

2021 ◽  
Vol 672 (1) ◽  
pp. 012071
Author(s):  
N K I Mayasti ◽  
R Kumalasari ◽  
R Ekafitri ◽  
D Desnilasari ◽  
D N Surahman ◽  
...  
Keyword(s):  
Raw Material ◽  
Selection Of
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