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Joseph C. Patrick
Dr. Joseph Cecil Patrick (August 28, 1892 – April 12, 1965) invented Thiokol, America's first synthetic rubber in the early 1920s. While seeking a formulation for automotive antifreeze, he attempted to hydrolyze ethylene dichloride with sodium polysulfide. In doing so, he produced a brown, insoluble gum that later became known as Thiokol. He solved commercial production problems by inventing the suspension polymerization process, and solved compounding problems by degrading high molecular weight polymer to a low molecular weight liquid polymer. This material is one of the principal binders for rocket propellant. Patrick was the 1958 recipient of the Charles Goodyear Medal The Charles Goodyear Medal is the highest honor conferred by the American Chemical Society, Rubber Division. Established in 1941, the award is named after Charles Goodyear, the discoverer of vulcanization, and consists of a gold medal, a framed c .... References Polymer scientists and engineers 1892 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiokol
Thiokol (variously Thiokol Chemical Corporation(/Company), Morton Thiokol Inc., Cordant Technologies Inc., Thiokol Propulsion, AIC Group, ATK Thiokol, ATK Launch Systems Group; finally Orbital ATK before becoming part of Northrop Grumman) was an American corporation concerned initially with rubber and related chemicals, and later with rocket and missile propulsion systems. Its name is a portmanteau of the Greek words for sulfur (θεῖον ''"theion"'') and glue (κόλλα ''"kolla"''), an allusion to the company's initial product, Thiokol polymer. The Thiokol Chemical Company was founded in 1929. Its initial business was a range of synthetic rubber and polymer sealants. Thiokol was a major supplier of liquid polymer sealants during World War II. When scientists at the Jet Propulsion Laboratory discovered that Thiokol's polymers made ideal binders for solid rocket fuels, Thiokol moved into the new field, opening laboratories at Elkton, Maryland, and later production facilitie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synthetic Rubber
A synthetic rubber is an artificial elastomer. They are polymers synthesized from petroleum byproducts. About 32-million metric tons of rubbers are produced annually in the United States, and of that amount two thirds are synthetic. Synthetic rubber, just like natural rubber, has many uses in the automotive industry for tires, door and window profiles, seals such as O-rings and gaskets, hoses, belts, matting, and flooring. They offer a different range of physical and chemical properties, so can improve the reliability of a given product or application. Synthetic rubbers are superior to natural rubbers in two major respects, thermal stability and resistance to oils and related compounds. They are more resistant to oxidizing agents, such as oxygen and ozone which can reduce the life of products like tires. History of synthetic rubber The expanded use of bicycles, and particularly their pneumatic tires, starting in the 1890s, created increased demand for rubber. In 1909, a team he ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrolyze
Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolysis is the cleavage of biomolecules where a water molecule is consumed to effect the separation of a larger molecule into component parts. When a carbohydrate is broken into its component sugar molecules by hydrolysis (e.g., sucrose being broken down into glucose and fructose), this is recognized as saccharification. Hydrolysis reactions can be the reverse of a condensation reaction in which two molecules join into a larger one and eject a water molecule. Thus hydrolysis adds water to break down, whereas condensation builds up by removing water. Types Usually hydrolysis is a chemical process in which a molecule of water is added to a substance. Sometimes this addition causes both the substance and water molecule to split into two parts. In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethylene Dichloride
The chemical compound 1,2-dichloroethane, commonly known as ethylene dichloride (EDC), is a chlorinated hydrocarbon. It is a colourless liquid with a chloroform-like odour. The most common use of 1,2-dichloroethane is in the production of vinyl chloride, which is used to make polyvinyl chloride (PVC) pipes, furniture and automobile upholstery, wall coverings, housewares, and automobile parts. 1,2-Dichloroethane is also used generally as an intermediate for other organic chemical compounds, and as a solvent. It forms azeotropes with many other solvents, including water (at a boiling point of ) and other chlorocarbons. History In 1794, physician Jan Rudolph Deiman, merchant Adriaan Paets van Troostwijk, chemist Anthoni Lauwerenburg, and botanist Nicolaas Bondt, under the name of Society of Dutch Chemists ( nl, Gezelschap der Hollandsche Scheikundigen), were the first to produce 1,2-dichloroethane from olefiant gas (oil-making gas, ethylene) and chlorine gas. Although the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Polysulfide
Sodium polysulfide is a general term for salts with the formula Na2 Sx, where ''x'' = 2 to 5. The species Sx2−, called polysulfide anions, include disulfide (S22−), trisulfide (S32−), tetrasulfide (S42−), and pentasulfide (S52−). In principle, but not in practice, the chain lengths could be longer. The salts are dark red solids that dissolve in water to give highly alkaline and corrosive solutions. In air, these salts oxidize, and they evolve hydrogen sulfide by hydrolysis. Structure The polysulfide anions form chains with S---S bond distances around 2 Å in length. The chains adopt skewed conformations. In the solid state, these salts are dense solids with strong association of the sodium cations with the anionic termini of the chains. Production and occurrence Sodium polysulfide can be produced by dissolving sulfur in a solution of sodium sulfide. Alternatively they are produced by the redox reaction of aqueous sodium hydroxide with sulfur at elevated temperature ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suspension Polymerization
Suspension polymerization is a heterogeneous radical polymerization process that uses mechanical agitation to mix a monomer or mixture of monomers in a liquid phase, such as water, while the monomers polymerize, forming spheres of polymer. The monomer droplets (size of the order 10-1000 μm) are suspended in the liquid phase. The individual monomer droplets can be considered as undergoing bulk polymerization. The liquid phase outside these droplets help in better conduction of heat and thus tempering the increase in temperature. While choosing a liquid phase for suspension polymerization, low viscosity, high thermal conductivity and low temperature variation of viscosity are generally preferred. The primary advantage of suspension polymerization over other types of polymerization is that a higher degree of polymerization can be achieved without monomer boil-off. During this process, there is often a possibility of these monomer droplets to stick to each other and cause creaming i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rocket Propellant
Rocket propellant is the reaction mass of a rocket. This reaction mass is ejected at the highest achievable velocity from a rocket engine to produce thrust. The energy required can either come from the propellants themselves, as with a chemical rocket, or from an external source, as with ion engines. Overview Rockets create thrust by expelling mass rear-ward, at high velocity. The thrust produced can be calculated by multiplying the mass flow rate of the propellants by their exhaust velocity relative to the rocket (specific impulse). A rocket can be thought of as being accelerated by the pressure of the combusting gases against the combustion chamber and nozzle, not by "pushing" against the air behind or below it. Rocket engines perform best in outer space because of the lack of air pressure on the outside of the engine. In space it is also possible to fit a longer nozzle without suffering from flow separation. Most chemical propellants release energy through redox chemistry, m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charles Goodyear Medal
The Charles Goodyear Medal is the highest honor conferred by the American Chemical Society, Rubber Division. Established in 1941, the award is named after Charles Goodyear, the discoverer of vulcanization, and consists of a gold medal, a framed certificate and prize money. The medal honors individuals for "outstanding invention, innovation, or development which has resulted in a significant change or contribution to the nature of the rubber industry". Awardees give a lecture at an ACS Rubber Division meeting, and publish a review of their work in the society's scientific journal '' Rubber Chemistry and Technology''. Recipients Source: * 1941 David Spence – Diamond Rubber Co. researcher noted for synthesizing isoprene for use in synthetic rubber * 1942 Lorin B. Sebrell – Goodyear Research Director noted for his work on organic accelerators for vulcanization * 1944 Waldo L. Semon – early developer of synthetic rubber, in particular Ameripol for B. F. Goodrich * 1946 I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymer Scientists And Engineers
A polymer (; Greek ''poly-'', "many" + '' -mer'', "part") is a substance or material consisting of very large molecules called macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic and natural polymers play essential and ubiquitous roles in everyday life. Polymers range from familiar synthetic plastics such as polystyrene to natural biopolymers such as DNA and proteins that are fundamental to biological structure and function. Polymers, both natural and synthetic, are created via polymerization of many small molecules, known as monomers. Their consequently large molecular mass, relative to small molecule compounds, produces unique physical properties including toughness, high elasticity, viscoelasticity, and a tendency to form amorphous and semicrystalline structures rather than crystals. The term "polymer" derives from the Greek word πολύς (''polus'', meaning "many, much") and μέρος (''meros'', meani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1892 Births
Year 189 ( CLXXXIX) was a common year starting on Wednesday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Silanus and Silanus (or, less frequently, year 942 ''Ab urbe condita''). The denomination 189 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years. Events By place Roman Empire * Plague (possibly smallpox) kills as many as 2,000 people per day in Rome. Farmers are unable to harvest their crops, and food shortages bring riots in the city. China * Liu Bian succeeds Emperor Ling, as Chinese emperor of the Han Dynasty. * Dong Zhuo has Liu Bian deposed, and installs Emperor Xian as emperor. * Two thousand eunuchs in the palace are slaughtered in a violent purge in Luoyang, the capital of Han. By topic Arts and sciences * Galen publishes his ''"Treatise on the various temperament ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1965 Deaths
Events January–February * January 14 – The Prime Minister of Northern Ireland and the Taoiseach of the Republic of Ireland meet for the first time in 43 years. * January 20 ** Lyndon B. Johnson is Second inauguration of Lyndon B. Johnson, sworn in for a full term as President of the United States. ** Indonesian President Sukarno announces the withdrawal of the Indonesian government from the United Nations. * January 30 – The Death and state funeral of Winston Churchill, state funeral of Sir Winston Churchill takes place in London with the largest assembly of dignitaries in the world until the 2005 funeral of Pope John Paul II. * February 4 – Trofim Lysenko is removed from his post as director of the Institute of Genetics at the Russian Academy of Sciences, Academy of Sciences in the Soviet Union. Lysenkoism, Lysenkoist theories are now treated as pseudoscience. * February 12 ** The African and Malagasy Republic, Malagasy Common Organization ('; OCA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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