Download or read book Review of Studies of the Radiation Modification of Elastomers written by T. Achmatowicz and published by . This book was released on 1969 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt: The influence of ionizing radiation on the vulcanization of natural rubber, latex, and sulfur vulcanates of butyl rubber as well as the role played by solid additives (oxides and halides of metals, and organic sensitizers) was investigated. Natural rubber with inorganic additives undergoes crosslinking under gamma radiation, and the rate of crosslinking increases with the atomic number of the metal with the exception of CuO and PbO. Chloroform was studied as an organic sensitizer, and this compound greatly accelerates the crosslinking process. Polyisobutylene and the vulcanates of butyl rubber undergo deep gradation under gamma radiation; however, the degradation products have valuable properties and may be used for production of sealing compositions. Radiation methods for reclamation of old motor tires and old butyl tubes were developed. (Author).

Download or read book Elastomers for Use in Radiation Fields written by Robert Harrington and published by . This book was released on 1960 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Elastomers for Use in Radiation Fields written by Robert Harrington and published by . This book was released on 1959 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advanced Elastomers written by Anna Boczkowska and published by BoD – Books on Demand. This book was released on 2012-09-12 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an extensive overview of current trends in the area of elastomers and their composites from the chapters contributed by internationally recognized specialists. The book deals with novel synthesis, modelling and experimental methods in elastomers. Contents include: new approach to crosslinking, liquid crystal elastomers, nanocomposites, smart elastomers, elastomers in microelectronics and microfluidics, elastomers in cement concrete and mortar, experimental testing and modelling. Each section demonstrates how enhancements in materials, processes and characterization techniques can improve performance in the field of engineering. The book provides a unique opportunity to discover the latest research on elastomer advances from laboratories around the world. This book addresses to industrial and academic researchers in the fields of physical, chemical, biological sciences and engineering.

Download or read book Advances in Elastomers II written by P. M. Visakh and published by Springer Science & Business Media. This book was released on 2013-04-09 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the second volume of a two-volume work which summarizes in an edited format and in a fairly comprehensive manner many of the recent technical research accomplishments in the area of Elastomers. “Advances in Elastomers” discusses the various attempts reported on solving these problems from the point of view of the chemistry and the structure of elastomers, highlighting the drawbacks and advantages of each method. It summarize the importance of elastomers and their multiphase systems in human life and industry, and covers all the topics related to recent advances in elastomers, their blends, IPNs, composites and nanocomposites. This second volume is deals with composites and nanocomposites of elastomers.

Download or read book Advances in Elastomers I written by P. M. Visakh and published by Springer Science & Business Media. This book was released on 2013-03-29 with total page 497 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first volume of a two-volume work which summarizes in an edited format and in a fairly comprehensive manner many of the recent technical research accomplishments in the area of Elastomers. “Advances in Elastomers” discusses the various attempts reported on solving these problems from the point of view of the chemistry and the structure of elastomers, highlighting the drawbacks and advantages of each method. It summarize the importance of elastomers and their multiphase systems in human life and industry, and covers all the topics related to recent advances in elastomers, their blends, IPNs, composites and nanocomposites. This first volume focuses on advances on the blends and interpenetrating networks (IPNs) of elastomers.

Download or read book High Energy Radiation of Polymers written by United States. Arsenal. Rock Island, Ill. Laboratory and published by . This book was released on 1953 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radiation Damage to Elastomers Plastics and Organic Liquids written by General Electric Company. Aircraft Nuclear Propulsion Department and published by . This book was released on 1956 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radiation Induced Stress Relaxation in Silicone and Polyurethane Elastomers written by and published by . This book was released on 2007 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many different materials are used in the National Ignition Facility, NIF, located at Lawrence Livermore National Laboratory, LLNL. Some of these are exposed to significant doses of ionizing radiation. Two elastomers are of special interest because they are used in sealing applications with long expected lifetimes. These are LPU4, a polyurethane formulated at LLNL, and Dow Corning DC93-500, a silicone RTV elastomer. In 2004 a program to determine the impact of ionizing radiation on the stress relaxation and compression set characteristics of these two elastomers was undertaken. Since the materials are used in continuous compression and must reliably seal, the primary test utilized was a stress relaxation test. This test provides insight into the ability of a seal to remain functional in a static seal. The test determines how much residual force remains after a certain period of time under compression. The temperature and absorbed radiation dose can dramatically impact this property. In this study the only independent environmental variable studied is the effect of radiation at ambient temperatures. Two levels of radiation exposure were studied, 1 MRad, and 10 MRad. One of the independent test parameters is the compression deflection during storage and in this test the value used was 25%. The need for a compression retention mechanism ruled out radiation exposure in the compressed direction since the high atomic number materials for that device would block the radiation. Therefore, an annular ring was chosen for the specimen shape. The procedures are, as closely as possible, based on ASTM D 6147-97. Since the data is readily obtained at the end of the stress relaxation test, the samples were also evaluated for compression set. Compression set is the essentially permanent deformation incurred in a seal after the seal is compressed for some period of time and then unloaded. Though this is indicative of potential sealing reliability, it is not as direct an indicator of seal performance as is stress relaxation. Compression set does not yield any useable, quantified information but is an indicator of viscoelastic deformation with time. The needed thickness measurements were obtained both from the unloading curves and direct measurement in general accordance with ASTM D395-03. The radiation source for this testing was the Co60 gamma source located at Lawrence Livermore National Laboratory (LLNL). This source has an exposure vessel approximately 29.2cm (11.5-inch) tall with an inside diameter of 7.44cm (2.93-inch). Because of the geometry limits, cylindrical symmetry and limited volume, a standard stress relaxation test such as ASTM D 6147-97 could not be utilized and a modified test was developed. An additional constraint imposed by the vertical asymmetry of the radiation dose in the exposure chamber was a limited height with reasonably uniform radiation exposure. The specific dimensions and radiation characteristics of the test cell are in Appendix A.

Download or read book Effects of Gamma Irradiation on Epdm Elastomers written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Two formulations of EPDM elastomer, one substituting a UV stabilizer for the normal antioxidant in this polymer, and the other the normal formulation, were synthesized and samples of each were exposed to gamma irradiation in initially pure deuterium gas to compare their radiation stability. Stainless steel containers having rupture disks were designed for this task. After 130 MRad dose of cobalt-60 radiation in the SRNL Gamma Irradiation Facility, a significant amount of gas was created by radiolysis; however the composition indicated by mass spectroscopy indicated an unexpected increase in the total amount deuterium in both formulations. The irradiated samples retained their ductility in a bend test. No change of sample weight, dimensions, or density was observed. No change of the glass transition temperature as measured by dynamic mechanical analysis was observed, and most of the other dynamic mechanical properties remained unchanged. There appeared to be an increase in the storage modulus of the irradiated samples containing the UV stabilizer above the glass transition, which may indicate hardening of the material by radiation damage. Polymeric materials become damaged by exposure over time to ionizing radiation. Despite the limited lifetime, polymers have unique engineering material properties and polymers continue to be used in tritium handling systems. In tritium handling systems, polymers are employed mainly in joining applications such as valve sealing surfaces (eg. Stem tips, valve packing, and O-rings). Because of the continued need to employ polymers in tritium systems, over the past several years, programs at the Savannah River National Laboratory have been studying the effect of tritium on various polymers of interest. In these studies, samples of materials of interest to the SRS Tritium Facilities (ultra-high molecular weight polyethylene (UHMW-PE), polytetrafluoroethylene (PTFE, Teflon{reg_sign}), Vespel{reg_sign} polyimide, and the elastomer ethylene propylene diene monomer (EPDM)) have been exposed in closed containers to tritium gas initially at 1 atmosphere pressure. These studies have demonstrated the degradation of properties when exposed to tritium gas. Also, the radiolytic production of significant amounts of hydrogen has been observed for UHMW-PE and EPDM. The study documented in this report exposes two similar formulations of EPDM elastomer to gamma irradiation in a closed container backfilled with deuterium. Deuterium is chemically identical to protium and tritium, but allows the identification of protium that is radiolytically produced from the samples. The goal of this program is to compare and contrast the response of EPDM exposure to two different types of ionizing radiation in a similar chemical environment.

Download or read book Abrasion Resistance of Elastomers Modified by Ionizing Radiation written by Feng-Jon Chang and published by . This book was released on 1996 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Current Topics in Elastomers Research written by Anil K. Bhowmick and published by CRC Press. This book was released on 2008-05-07 with total page 1105 pages. Available in PDF, EPUB and Kindle. Book excerpt: From weather-proof tires and artificial hearts to the o-rings and valve seals that enable successful space exploration, rubber is an indispensable component of modern civilization. Stiff competition and stringent application requirements foster continuous challenges requiring manufacturers to fund ever-expanding research projects. However, this vas

Download or read book Zur Erinnerung an Frau Ida Barell Leuzinger gestorben in Basel am 19 Februar 1927 written by and published by . This book was released on 1927 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book WADC Technical Report written by United States. Wright Air Development Division and published by . This book was released on 1955 with total page 1910 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Effect of Radiation on Properties of Polymers written by Laurence W. McKeen and published by William Andrew. This book was released on 2020-09-09 with total page 430 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Effect of Radiation on Properties of Polymers examines the effects of radiation on plastics and elastomers. Polymers are required in products or parts for a range of cutting-edge applications that are exposed to radiation, in areas such as space, medicine, and radiation processing. This book focuses on the effects of radiation exposure within that environment, providing in-depth data coverage organized by category of polymer. Aspects such as radiation impact on mechanical and thermal properties, including glass transition and heat deflection temperatures, are described, demonstrating how changes in these properties affect the performance of plastic or elastomer parts. The effect of radiation on electrical properties is also included. Supporting introductory chapters explain the key concepts of radiation, including the physical, mechanical, and thermal properties of plastics and elastomers. This is a vital resource for plastics engineers, product designers, and R&D professionals, working on products or parts for radioactive environments, as well as engineers and scientists in the medical, nuclear, and radiation processing industries. The book also supports researchers and scientists in plastics engineering, polymer processing and properties, polymer and coatings chemistry, materials science, and radiation. Brings together highly valuable data on the effect of radiation on the properties of polymers and elastomers Enables the reader to compare properties and to select the best possible materials for specific applications Supported by detailed explanations and analysis, ensuring that the reader understands how to interpret and utilize the data

Download or read book In situ Structure Characterization of Elastomers during Deformation and Fracture written by Karsten Brüning and published by Springer. This book was released on 2016-09-10 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis offers novel insights into the time-dependent structural evolution of polymers under deformation. In-situ tensile experiments at high-brilliance synchrotron sources allowed to characterize the material with unrivaled resolution in time and space. The strain-induced crystallization in natural rubber was studied by wide-angle X-ray diffraction. Special emphasis was put on the establishment of new structure-property relationships to give a more in-depth understanding of the mechanical performance of rubber parts, e.g. in tear fatigue loading. To this end, the kinetics of strain-induced crystallization were investigated, subjecting the material to high strain rates. The local structure around a crack tip was observed by scanning wide-angle X-ray diffraction. Ultra-small angle X-ray scattering served to study filled elastomers under deformation, from specially prepared model filler systems to industrially relevant carbon black filled rubbers. Other methods include electron microscopy coupled with in-situ tensile testing and optical dilatometry to examine cavitation in rubbers. The underlying theory as well as a literature review are covered by an extensive introductory chapter, followed by a description of the experimental techniques. The results are presented in more detail than in the original journal publications.

Download or read book Radiation Effects on Polymers written by Roger Lee Clough and published by . This book was released on 1991 with total page 656 pages. Available in PDF, EPUB and Kindle. Book excerpt: Here is the most extensive resource on polymer radiation effects to be available in more than a decade. This new volume reviews the fundamental chemistry and physics of polymer-radiation interaction and examines recent progress in most major areas of the field. Its 38 chapters, written by leading experts from around the world, cover: fundamentals of polymer radiation chemistry; technological applications of radiation to polymers (including radiation processing; radiation curing; sterilization; cross-linking, polymerization, grafting, X-ray resists, and others); and degradation of stabilization of irradiated polymers (including nuclear plants, scintillation detectors for particle physics, and others).