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Styrene
Styrene is an organic compound with the chemical formula C6H5CH=CH2. Its structure consists of a vinyl group as substituent on benzene. Styrene is a colorless, oily liquid, although aged samples can appear yellowish. The compound evaporates easily and has a sweet smell, although high concentrations have a less pleasant odor. Styrene is the precursor to polystyrene and several copolymers, and is typically made from benzene for this purpose. Approximately 25 million tonnes of styrene were produced in 2010, increasing to around 35 million tonnes by 2018. Natural occurrence Styrene is named after storax balsam (often commercially sold as ''styrax''), the resin of Liquidambar trees of the Altingiaceae plant family. Styrene occurs naturally in small quantities in some plants and foods (cinnamon, coffee beans, balsam tree (other), balsam trees and peanuts) and is also found in coal tar. History In 1839, the German apothecary Eduard Simon isolated a volatile liquid from t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polystyrene
Polystyrene (PS) is a synthetic polymer made from monomers of the aromatic hydrocarbon styrene. Polystyrene can be solid or foamed. General-purpose polystyrene is clear, hard, and brittle. It is an inexpensive resin per unit weight. It is a poor barrier to air and water vapor and has a relatively low melting point. Polystyrene is one of the most widely used plastics, with the scale of its production being several million tonnes per year. Polystyrene is naturally transparent to visible light, but can be colored with colorants. Uses include protective packaging (such as packing peanuts and optical disc jewel cases), containers, lids, bottles, trays, tumblers, disposable cutlery, in the making of models, and as an alternative material for phonograph records. As a thermoplastic polymer, polystyrene is in a solid (glassy) state at room temperature but flows if heated above about 100 °C, its glass transition temperature. It becomes rigid again when cooled. This te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
August Wilhelm Von Hofmann
August Wilhelm von Hofmann (8 April 18185 May 1892) was a German chemist who made considerable contributions to organic chemistry. His research on aniline helped lay the basis of the aniline-dye industry, and his research on coal tar laid the groundwork for his student Charles Mansfield's practical methods for extracting benzene and toluene and converting them into nitro compounds and amines. Hofmann's discoveries include formaldehyde, hydrazobenzene, the isonitriles, and allyl alcohol. He prepared three ethylamines and tetraethylammonium compounds and established their structural relationship to ammonia. After studying under Justus von Liebig at the University of Giessen, Hofmann became the first director of the Royal College of Chemistry, now part of Imperial College London, in 1845. In 1865 he returned to Germany to accept a position at the University of Berlin as a teacher and researcher. After his return he co-founded the German Chemical Society (''Deutsche Chemis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Storax Balsam
Storax (; , ''stúrax''), often commercially sold as styrax, is a natural fragrant resin isolated from the wounded bark of ''Liquidambar orientalis'' Mill. (Asia Minor) and ''Liquidambar styraciflua'' L. (Eastern US, Mexico, Central America) (Altingiaceae). It is distinct from benzoin (also called "storax"), a similar resin obtained from the Styracaceae plant family. Composition Purified storax contains circa 33–50% storesin, an alcoholic resin, both free and as cinnamic esters. It contains 5–15% cinnamic acid, 5–15% cinnamyl cinnamate, circa 10% phenylpropyl cinnamate; small amounts of ethyl cinnamate, benzyl cinnamate, and styrene. Some may contain traces of vanillin. Some sources report a resin containing triterpenic acids ( oleanolic and 3-epioleanolic acids). Uses Storax has a pleasant, floral/lilac, leathery, balsamic smell. Storax and its derivatives ( resinoid, essential oil, absolute) are used as flavors, fragrances, and in pharmaceuticals ( Friar's Balsam). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Probable Carcinogen
A carcinogen () is any agent that promotes the development of cancer. Carcinogens can include synthetic chemicals, naturally occurring substances, physical agents such as ionizing and non-ionizing radiation, and biologic agents such as viruses and bacteria. Most carcinogens act by creating mutations in DNA that disrupt a cell's normal processes for regulating growth, leading to uncontrolled cellular proliferation. This occurs when the cell's DNA repair processes fail to identify DNA damage allowing the defect to be passed down to daughter cells. The damage accumulates over time. This is typically a multi-step process during which the regulatory mechanisms within the cell are gradually dismantled allowing for unchecked cellular division. The specific mechanisms for carcinogenic activity is unique to each agent and cell type. Carcinogens can be broadly categorized, however, as activation-dependent and activation-independent which relate to the agent's ability to engage direc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzene
Benzene is an Organic compound, organic chemical compound with the Chemical formula#Molecular formula, molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar hexagonal Ring (chemistry), ring with one hydrogen atom attached to each. Because it contains only carbon and hydrogen atoms, benzene is classed as a hydrocarbon. Benzene is a natural constituent of petroleum and is one of the elementary petrochemicals. Due to the cyclic continuous pi bonds between the carbon atoms, benzene is classed as an aromatic hydrocarbon. Benzene is a colorless and highly Combustibility and flammability, flammable liquid with a sweet smell, and is partially responsible for the aroma of gasoline. It is used primarily as a Precursor (chemistry), precursor to the manufacture of chemicals with more complex structures, such as ethylbenzene and cumene, of which billions of kilograms are produced annually. Although benzene is a major Chemical industry, industrial che ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Society Of Chemistry
The Royal Society of Chemistry (RSC) is a learned society and professional association in the United Kingdom with the goal of "advancing the chemistry, chemical sciences". It was formed in 1980 from the amalgamation of the Chemical Society, the Royal Institute of Chemistry, the Faraday Society, and the Society for Analytical Chemistry with a new Royal Charter and the dual role of learned society and professional body. At its inception, the Society had a combined membership of 49,000 in the world. The headquarters of the Society are at Burlington House, Piccadilly, London. It also has offices in Thomas Graham House in Cambridge (named after Thomas Graham (chemist), Thomas Graham, the first president of the Chemical Society) where ''RSC Publishing'' is based. The Society has offices in the United States, on the campuses of The University of Pennsylvania and Drexel University, at the University City Science Center in Philadelphia, Pennsylvania, in both Beijing and Shanghai, People' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peanut
The peanut (''Arachis hypogaea''), also known as the groundnut, goober (US), goober pea, pindar (US) or monkey nut (UK), is a legume crop grown mainly for its edible seeds. It is widely grown in the tropics and subtropics by small and large commercial producers, both as a grain legume and as an oil crop. Atypically among legumes, peanut pods geocarpy, develop underground; this led botanist Carl Linnaeus to name peanuts ''hypogaea'', which means "under the earth". The peanut belongs to the botanical family Fabaceae (or Leguminosae), commonly known as the legume, bean, or pea family. Like most other legumes, peanuts harbor symbiotic nitrogen-fixing bacteria in root nodules, which improve soil fertility, making them valuable in crop rotations. Despite not meeting the Botanical nut, botanical definition of a nut as "a fruit whose ovary (botany), ovary wall becomes hard at maturity," peanuts are usually categorized as nuts for culinary purposes and in common English. Some pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coal Tar
Coal tar is a thick dark liquid which is a by-product of the production of coke and coal gas from coal. It is a type of creosote. It has both medical and industrial uses. Medicinally it is a topical medication applied to skin to treat psoriasis and seborrheic dermatitis ( dandruff). It may be used in combination with ultraviolet light therapy. Industrially it is a railroad tie preservative and used in the surfacing of roads. Coal tar was listed as a known human carcinogen in the first Report on Carcinogens from the U.S. Federal Government, issued in 1980. Coal tar was discovered circa 1665 and used for medical purposes as early as the 1800s. Circa 1850, the discovery that it could be used as the main raw material for the synthesis of dyes engendered an entire industry. It is on the World Health Organization's List of Essential Medicines. Coal tar is available as a generic medication and over the counter. Side effects include skin irritation, sun sensitivity, aller ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eduard Simon
Johann Eduard Simon (18 September 1789 – 19 June 1856) was an apothecary in Berlin, Germany. Johann Eduard Simon accidentally discovered polystyrene in 1839. Simon distilled an oily substance from storax Storax (; , ''stúrax''), often commercially sold as styrax, is a natural fragrant resin isolated from the wounded bark of ''Liquidambar orientalis'' Mill. (Asia Minor) and ''Liquidambar styraciflua'' L. (Eastern US, Mexico, Central America) (A ..., the resin of the Sweetgum tree, '' Liquidambar orientalis'', which he named "styrol". Several days later he found that the styrol had thickened, presumably due to polymerisation, into a jelly which he dubbed styrol oxide ("Stryroloxyd").Scheirs, John"Historical Overview of Syrenic Polymers"in Notes 19th-century German chemists German apothecaries 1789 births 1856 deaths Chemists from the Kingdom of Prussia {{Germany-engineer-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Buddle Blyth
John Buddle Blyth (1814 – 24 December 1871) was a Jamaican-born chemist who was the first professor of chemistry at Queen's College Cork in Ireland. With August Wilhelm von Hofmann, he was the first to report photopolymerisation which they observed when styrene became metastyrol after exposure to sunlight. Early life and family John Blyth was born in Jamaica in 1814 to John Blythe and Mary Buddle, a "free woman of colour". He was baptised at Mesopotamia in Westmoreland Parish on 11 April 1816 by Edmund Pope, rector of Westmorland, and described as a "free child of colour".John Buddle Blyth Jamaica, Church of England Parish Register Transcripts, 1664-1880. Family Search. Retrieved 12 January 2019. He had brothers Charles ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liquidambar Styraciflua
''Liquidambar styraciflua'', commonly known as the American sweetgum among other names, is a deciduous tree in the genus ''Liquidambar'' native to warm temperate areas of eastern North America and tropical montane regions of Mexico and Central America. Sweetgum is one of the main valuable forest trees in the southeastern United States, and is a popular ornamental tree in temperate zone, temperate climates. It is recognizable by the combination of its five-pointed star-shaped leaves (similar to maple leaves) and its hard, spiked fruits. It is currently classified in the plant family (biology), family Altingiaceae, but was formerly considered a member of the Hamamelidaceae. Names This plant's genus name ''Liquidambar'' was first given by Carl Linnaeus, Linnaeus in 1753 from the Latin ('fluid') and the Arabic ('amber'), in allusion to the fragrant terebinthine juice or gum which exudes from the tree. Its botanical name, specific epithet ''styraciflua'' is an old generic name meani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
