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24-506: The conglomerate is composed of 186 subsidiaries and affiliates that share the SK brand name and the group's management culture, named SKMS (SK Management System). It changed its name from Sunkyong Group ( 선경그룹 ; 鮮京그룹 ) to SK Group in 1998. The group is controlled by estate of Chey Tae-won through a holding company, SK Inc. The cornerstone of SK Group is its energy and chemicals division. While its largest businesses are primarily involved in

48-518: A chemical used in manufacturing polyurethane ) production technology from Germany in May 2006. It is scheduled to produce 100,000 tons of PO from 2008. At the end of 2005, SK Corp. developed a lithium-ion battery separator (LiBS) for the first time in Korea, and started selling the product in 2006. In July 2007, SK Group adopted a holding company structure. Under the re-organization, SK's main entity, SK Corporation,

72-399: A fire, sealed tanks of propylene oxide should be cooled with fire hoses to prevent explosion from self-polymerization. When burning in open air however, water can transport propylene oxide outside of the fire zone which can reignite upon floating to the surface. Additional firefighting measures should be taken to prevent propylene oxide from washing out to nearby drains and sewers contaminating

96-543: A joint venture between two Japanese companies, Senman Chutan and Kyoto -based Kyoto Orimono Company) from South Korean government as abandoned property of Japan in 1953. In 1958, the company manufactured Korea's first polyester fiber on company grounds. It established Sunkyong Fibers Ltd. in July 1969, and started to produce original yarn. In 1973, SK then established Sunkyong Oil, beginning a vertical integration strategy to manage production, "From Petroleum to Fibers". That same year,

120-422: A new drug candidate for schizophrenia , in 2003. In 2002, SK Telecom successfully launched the world's first commercial CDMA 1X EV-DO technology, allowing it to offer 3G telecommunications service. In 2004, SK Telecom enabled satellite DMB service by deploying the world's first DMB satellite. Moreover, in 2006, SK began revitalizing the 3.5-generation mobile phone market and in the following year, completed

144-434: A typical procedure, the sample is first immersed in a mixture of equal volumes of ethanol and propylene oxide for 5 minutes, and then four times in pure oxide, 10 minutes each. Propylene oxide is sometimes used in thermobaric munitions as the fuel in fuel–air explosives. In addition to the explosive damage from the blast wave , unexploded propylene oxide can cause additional effects from direct toxicity. Propylene oxide

168-636: Is an extremely flammable liquid, and its vapors can form explosive mixtures with air at concentrations as low as 2.3% ( Lower Explosive Limit ). Propylene oxide vapor is twice as dense as air . When exposed to an open atmosphere, the vapor can accumulate in low-lying areas while spreading out over long distances and reach ignition source, causing flashback or an explosion. When heated, propylene oxide can rapidly self-polymerize and decompose producing other toxic gases such as carbon monoxide and various free radicals . Propylene oxide fires are especially dangerous and difficult for firefighters to extinguish. In

192-399: Is both acutely toxic and carcinogenic . Acute exposure causes respiratory tract irritation , eventually leading to death. Signs of toxicity after acute exposure include salivation , lacrimation , nasal discharge, gasping, lethargy and hypoactivity , weakness, and incoordination. Propylene oxide is also neurotoxic in rats, and presumably in humans. Propylene oxide alkylates DNA and

216-606: Is chiral building block that is commercially available in either enantiomeric form (( R )-(+) and ( S )-(–)). The separated enantiomers can be obtained through a Co(III)-salen-catalyzed hydrolytic kinetic resolution of the racemic material. Like other epoxides, PO undergoes ring-opening reactions. With water, propylene glycol is produced. With alcohols, reactions, called hydroxylpropylation , analogous to ethoxylation occur. Grignard reagents add to propylene oxide to give secondary alcohols. Some other reactions of propylene oxide include: Between 60 and 70% of all propylene oxide

240-466: Is considered a mutagen for both animals and humans. Pregnant rats exposed to 500ppm of propylene oxide for less than 8 hours gave birth to litters with significant deformities and weight deficiencies. Similar exposure has also shown to reduce animal fertility. As such, it is a known animal carcinogen and potential human carcinogen, and is included into the List of IARC Group 2B carcinogens . Propylene oxide

264-455: Is converted to polyether polyols by the process called alkoxylation . These polyols are building blocks in the production of polyurethane plastics. About 20% of propylene oxide is hydrolyzed into propylene glycol , via a process which is accelerated by acid or base catalysis . Other major products are polypropylene glycol , propylene glycol ethers, and propylene carbonate . The United States Food and Drug Administration has approved

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288-527: Is produced on a large scale industrially. Its major application is its use for the production of polyether polyols for use in making polyurethane plastics. It is a chiral epoxide , although it is commonly used as a racemic mixture . This compound is sometimes called 1,2-propylene oxide to distinguish it from its isomer 1,3-propylene oxide, better known as oxetane . Industrial production of propylene oxide starts from propylene . Two general approaches are employed, one involving hydrochlorination and

312-508: Is then dehydrochlorinated. For example: Lime ( calcium hydroxide ) is often used to absorb the HCl . The other general route to propylene oxide involves oxidation of propylene with an organic peroxide . The reaction follows this stoichiometry: The process is practiced with four hydroperoxides : In principle, this process produces only water as a side product . In practice, some ring-opened derivatives of PO are generated. Propylene oxide

336-429: The energy , petroleum , and chemical industries, the group also owns the nation's largest wireless mobile phone service provider SK Telecom , and provides services in construction , marketing , local telephone communications, high-speed internet, and wireless broadband WiBro . Since 2012, SK Hynix , one of the world's largest random access memory and semiconductor manufacturers, has also been majority owned by

360-524: The Wikimedia System Administrators, please include the details below. Request from 172.68.168.151 via cp1112 cp1112, Varnish XID 384742515 Upstream caches: cp1112 int Error: 429, Too Many Requests at Fri, 29 Nov 2024 05:30:06 GMT Propylene oxide Propylene oxide is an acutely toxic and carcinogenic organic compound with the molecular formula C 3 H 6 O. This colourless volatile liquid with an odour similar to ether ,

384-1041: The company acquired the Walkerhill Hotel. In 1976, Sunkyong Corporation received an international trading company license from the Indian government. In December 1980 SK purchased privately run Korea National Oil, making it Korea's fifth largest conglomerate . In January 1988, crude oil was imported for processing to Korea from Yemen 's Marib oil field. In June 1994, SK entered Korea's telecommunications business by becoming Korea Mobile Telecommunication Service's largest shareholder. In January 1996, SK Telecom launched Korea's first commercial CDMA cellular phone service in Incheon and Bucheon . In 1998, Management re-branded Sunkyong to SK. In 1999, SK Chemicals developed third-generation (non cross resistant) platinum-complex anti-cancer agent. Also, by focusing its research and development efforts on life sciences, SK Corporation developed YKP1358,

408-485: The construction of the national HSDPA network. In May 2006, SK Telecom started the world's first commercial 3.5-generation HSDPA service, featuring high-quality video telephony and data transmission, and global roaming access. In 2005, SK Networks opened China's first two wholly foreign-owned, gas stations in Shenyang. Then, after exploring Brazilian mining area BM-C-8, SK Corporation developed an oil field where it confirmed

432-529: The end of 2018, supplying Kia and Mercedes. In July 2022, SK Group announced a $ 22 billion investment in the United States semiconductor, green energy bioscience and other technology industries. In total, SK Group will invest over $ 52 billion in the United States by 2025. SK Networks said August 20, 2024 it has sold its rental car unit for 820 billion won (US$ 618 million) to a Singapore-based private equity fund. In November 2024, SK Group Chairman Chey Tae-won

456-532: The existence of more than 50 million barrels of oil deposits. SK Gas began developing resources overseas when it participated in two mining areas to the west of Russia's Kamchatka peninsula in March 2006. In early 2006, SK Networks also developed Ecol-Green, a biodegradable plastic material. Incheon Oil officially started operations using the SK name in March 2006. SK Energy is currently engaged in 27 oil fields in 15 countries worldwide SKC imported propylene oxide (PO,

480-460: The group. As with many other chaebols , SK Group's chairmanship was 'inherited' from father to son: from its founder the late Chey Jong-hyon to its present chairman Chey Tae-won (eldest son). Chey Tae-won was married to the daughter of the former South Korean President Roh Tae-woo until 2015. SK Group began when the current founders acquired Sunkyong Textiles (founded during the Japanese rule as

504-399: The other involving oxidation . In 2005, about half of the world production was through chlorohydrin technology and one half via oxidation routes. The latter approach is growing in importance. The traditional route proceeds via the conversion of propene to propylene chlorohydrin according to the following simplified scheme: The mixture of 1-chloro-2-propanol and 2-chloro-1-propanol

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528-539: The use of propylene oxide to pasteurize raw almonds beginning on September 1, 2007, in response to two incidents of contamination by Salmonella in commercial orchards, one incident occurring in Canada and one in the United States. Pistachio nuts can also be subjected to propylene oxide to control Salmonella . Propylene oxide is commonly used in the preparation of biological samples for electron microscopy , to remove residual ethanol previously used for dehydration. In

552-541: Was appointed chairman of the board of directors of Soldigm, SK Hynix's U.S.-based NAND flash memory unit. SK's subsidiary companies all operate under the SK Management System (SKMS) which was developed, articulated and enhanced by SK's Chairman, Chey Tae-won . On April 7, 2008, SK Group launched a marketing and management company named "SK Marketing & Company" to pursue Chairman Chey's vision. Chey Tae-won Too Many Requests If you report this error to

576-586: Was split into an investment company, now SK Inc. and an operating company, now SK Energy. The subsidiary companies that now operate under the central SK Inc. umbrella include: SK Energy, SK Telecom, SK Networks, SKC, SK E&S, SK Shipping and K Power. SK acquired Hynix for US$ 3 billion in February 2012, rebranding it to SK Hynix. In February 2017, SK acquired the polyethylene acrylic acid business of Dow Chemical Company for $ 370 million, and planned to increase battery production capacity from 1.9 to 3.9 GWh per year at

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