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Herbert S. Eleuterio
Herbert S. Eleuterio (November 23, 1927 – July 17, 2022 ) was an American industrial chemist noted for technical contributions to catalysis, polymerization, industrial research management, and science education. In particular, he discovered the olefin metathesis reaction and several novel fluoropolymers. Additionally, he explored techniques for research leadership, especially methods for fostering collaboration, globalization, and scientific creativity. Eleuterio's discovery of olefin metathesis is cited as a compelling example of a scientific development originating in industry, subsequently being nurtured by academia, and returning to industry in commercially viable form. Early life and education Eleuterio was born in New Bedford, Massachusetts, to parents of Portuguese descent. He completed a B.S. in Chemistry at Tufts University in 1949. He continued on to graduate school at Michigan State University, pursuing physical organic chemistry. As part of his thesis research wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DuPont Co
DuPont de Nemours, Inc., commonly shortened to DuPont, is an American multinational chemical company first formed in 1802 by French-American chemist and industrialist Éleuthère Irénée du Pont de Nemours. The company played a major role in the development of Delaware and first arose as a major supplier of gunpowder. DuPont developed many polymers such as Vespel, neoprene, nylon, Corian, Teflon, Mylar, Kapton, Kevlar, Zemdrain, M5 fiber, Nomex, Tyvek, Sorona, Corfam and Lycra in the 20th century, and its scientists developed many chemicals, most notably Freon (chlorofluorocarbons), for the refrigerant industry. It also developed synthetic pigments and paints including ChromaFlair. In 2015, DuPont and the Dow Chemical Company agreed to a reorganization plan in which the two companies would merge and split into three. As a merged entity, DuPont simultaneously acquired Dow and renamed itself to DowDuPont on August 31, 2017, and after 18 months spin off the merged entity's mater ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetics
Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinian friar working in the 19th century in Brno, was the first to study genetics scientifically. Mendel studied "trait inheritance", patterns in the way traits are handed down from parents to offspring over time. He observed that organisms (pea plants) inherit traits by way of discrete "units of inheritance". This term, still used today, is a somewhat ambiguous definition of what is referred to as a gene. Trait inheritance and molecular inheritance mechanisms of genes are still primary principles of genetics in the 21st century, but modern genetics has expanded to study the function and behavior of genes. Gene structure and function, variation, and distribution are studied within the context of the cell, the organism (e.g. dominance), and within the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluorinated Ethylene Propylene
Fluorinated ethylene propylene (FEP) is a copolymer of hexafluoropropylene and tetrafluoroethylene. It differs from the polytetrafluoroethylene (PTFE) resins in that it is melt-processable using conventional injection molding and screw extrusion techniques. Fluorinated ethylene propylene was invented by DuPont and is sold under the brandname Teflon FEP. Other brandnames are Neoflon FEP from Daikin or Dyneon FEP from Dyneon/ 3M. FEP is very similar in composition to the fluoropolymers PTFE (polytetrafluoroethylene) and PFA (perfluoroalkoxy polymer resin). FEP and PFA both share PTFE's useful properties of low friction and non-reactivity, but are more easily formable. FEP is softer than PTFE and melts at 260 °C; it is highly transparent and resistant to sunlight. Production FEP is produced by free-radical polymerization of mixtures of tetrafluoroethylene and hexafluoropropylene. The mixture is biased to compensate for the relatively low reactivity of the propylene comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrafluoroethylene
Tetrafluoroethylene (TFE) is a fluorocarbon with the chemical formula C2 F4. It is the simplest perfluorinated alkene. This gaseous species is used primarily in the industrial preparation of fluoropolymers. Properties Tetrafluoroethylene is a colorless, odorless gas. Like all unsaturated fluorocarbons, it is susceptible to nucleophilic attack. It is unstable towards decomposition to carbon and carbon tetrafluoride () and prone to form explosive peroxides in contact with air. Industrial use Polymerization of tetrafluoroethylene produces polytetrafluoroethylene (PTFE) polymers such as Teflon and Fluon. PTFE is one of the two fluorocarbon resins composed wholly of fluorine and carbon. The other resin composed purely of carbon and fluorine is the copolymer of TFE with typically 6–9% hexafluoropropene (HFP), which is known as FEP (fluorinated ethylene propylene copolymer). TFE is also used in the preparation of numerous copolymers that also include hydrogen and/or oxygen, includ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexafluoropropylene
Hexafluoropropylene is the fluoroalkene with the formula CF3CF=CF2. It is the perfluorocarbon counterpart to the hydrocarbon propylene. It is mainly used to produce copolymers with tetrafluoroethylene. Hexafluoropropylene is used as a chemical intermediate. Preparation Hexafluoropropylene can be produced by pyrolysis of tetrafluoroethylene: :3CF2=CF2 → 2CF3CF=CF2 It can also be prepared from chlorodifluoromethane, or produced from various chlorofluorocarbons Chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) are fully or partly halogenated hydrocarbons that contain carbon (C), hydrogen (H), chlorine (Cl), and fluorine (F), produced as volatile derivatives of methane, ethane, and propan .... References Fluorocarbons Haloalkenes {{organohalide-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nobel Laureates
The Nobel Prizes ( sv, Nobelpriset, no, Nobelprisen) are awarded annually by the Royal Swedish Academy of Sciences, the Swedish Academy, the Karolinska Institutet, and the Norwegian Nobel Committee to individuals and organizations who make outstanding contributions in the fields of chemistry, physics, literature, peace, and physiology or medicine. They were established by the 1895 will of Alfred Nobel, which dictates that the awards should be administered by the Nobel Foundation. The Nobel Memorial Prize in Economic Sciences was established in 1968 by the Sveriges Riksbank, the central bank of Sweden, for contributions to the field of economics. Each recipient, a Nobelist or ''laureate'', receives a gold medal, a diploma, and a sum of money which is decided annually by the Nobel Foundation. Prize Each prize is awarded by a separate committee; the Royal Swedish Academy of Sciences awards the Prizes in Physics, Chemistry, and Economics; the Karolinska Institute awards the Priz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Synthesis
Organic synthesis is a special branch of chemical synthesis and is concerned with the intentional construction of organic compounds. Organic molecules are often more complex than inorganic compounds, and their synthesis has developed into one of the most important branches of organic chemistry. There are several main areas of research within the general area of organic synthesis: ''total synthesis'', ''semisynthesis'', and ''methodology''. Total synthesis A total synthesis is the complete chemical synthesis of complex organic molecules from simple, commercially available petrochemical or natural precursors. Total synthesis may be accomplished either via a linear or convergent approach. In a ''linear'' synthesis—often adequate for simple structures—several steps are performed one after another until the molecule is complete; the chemical compounds made in each step are called synthetic intermediates. Most often, each step in a synthesis refers to a separate rea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ring-opening Metathesis Polymerization
Ring-opening metathesis polymerization (ROMP) is a type of olefin metathesis chain-growth polymerization. The driving force of the reaction is relief of ring strain in cyclic olefins (e.g. norbornene or cyclopentene). A variety of heterogeneous and homogeneous catalysts have been developed. Most large-scale commercial processes rely on the former while some fine chemical syntheses rely on the homogeneous catalysts. Catalysts are based on transition metals such as W, Mo, Re, Ru, and Ti. Heterogeneous catalysis and applications : Ring-opening metathesis polymerization of cycloalkenes has been commercialized since the 1970s. Examples of polymers produced on an industrial level through ROMP catalysis are Vestenamer or trans-polyoctenamer, which is the metathetical polymer of cyclooctene. Norsorex or polynorbornene is another important ROMP product on the market. Telene and Metton are polydicyclopentadiene products produced in a side reaction of the polymerization of norbornene. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclopentene
Cyclopentene is a chemical compound with the formula . It is a colorless liquid with a petrol-like odor. It has few applications, and thus is mainly used as a minor component of gasoline, present in concentrations of less than 1%. It is one of the principal cycloalkenes. Production Cyclopentene is produced industrially in large amounts by steam cracking of naphtha. In the laboratory, it is prepared by dehydration of cyclopentanol. It can also produced by the catalytic hydrogenation of cyclopentadiene.D. Hönicke, R. Födisch, P. Claus, M. Olson: ''Cyclopentadiene and Cyclopentene'', in: '' Ullmanns Enzyklopädie der Technischen Chemie'' 2002, Wiley-VCH, Weinheim. Use in mechanistic organic chemistry Cyclopentene is used in analysing the mechanisms of organic reactions. It can be obtained from vinylcyclopropane in the vinylcyclopropane-cyclopentene rearrangement The vinylcyclopropane rearrangement or vinylcyclopropane-cyclopentene rearrangement is a ring expansion reaction, c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Norbornene
Norbornene or norbornylene or norcamphene is a highly strained bridged cyclic hydrocarbon. It is a white solid with a pungent sour odor. The molecule consists of a cyclohexene ring with a methylene bridge between carbons 1 and 4. The molecule carries a double bond which induces significant ring strain and significant reactivity. Production Norbornene is made by a Diels–Alder reaction of cyclopentadiene and ethylene. Many substituted norbornenes can be prepared similarly. Related bicyclic compounds are norbornadiene, which has the same carbon skeleton but with two double bonds, and norbornane which is prepared by hydrogenation of norbornene. Reactions Norbornene undergoes an acid-catalyzed hydration reaction to form norborneol. This reaction was of great interest in the elucidation of the non-classical carbonion controversy. Norbornene is used in the Catellani reaction and in norbornene-mediated ''meta''-C−H activation. Certain substituted norbornenes undergo unusual sub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catalysts
Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quickly, very small amounts of catalyst often suffice; mixing, surface area, and temperature are important factors in reaction rate. Catalysts generally react with one or more reactants to form intermediates that subsequently give the final reaction product, in the process of regenerating the catalyst. Catalysis may be classified as either homogeneous, whose components are dispersed in the same phase (usually gaseous or liquid) as the reactant, or heterogeneous, whose components are not in the same phase. Enzymes and other biocatalysts are often considered as a third category. Catalysis is ubiquitous in chemical industry of all kinds. Estimates are that 90% of all commercially produced chemical products involve catalysts at some sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DuPont Experimental Station
The DuPont Experimental Station is the largest research and development facility of DuPont. Located on the banks of the Brandywine Creek in Wilmington, Delaware, it is home to some of the most important discoveries of the modern chemical industry. Overview The Experimental Station marked its 100th anniversary in 2003. It was founded as an effort to move the DuPont Company from gunpowder and explosives into the new age of chemistry. /sup> The site overlooks the original powder mills upon which the company was founded - now Hagley Museum and Library. The Experimental Station is east from Hagley Museum and west-southwest from Nemours Children's Hospital, Delaware. As one of the first industrial research laboratories in the United States, the campus-style Experimental Station in Wilmington, Delaware, serves as the primary research and development facility for DuPont. It is home to DuPont's Central Research and most other business units of DuPont are also represented on site. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
