Misplaced Pages

#652347

74-425: Some of the past Winthrop-Sears medal winners include: William Wulfsohn (Ashland Global Holdings), Mario Nappa (Chemours), Peter McCausland (Airgas), Sol Barer (Celgene), Robert Gore (Gore-Tex), and Jon M. Huntsman ( Huntsman Chemical Corporation ). The Chemists’ Club was founded in 1898 and is the world’s longest serving International organization devoted to the furtherance of chemistry and related technologies. In

148-516: A density of about 2200 kg/m and a melting point of 600 K (327 °C; 620 °F). It maintains high strength, toughness and self-lubrication at low temperatures down to 5 K (−268.2 °C; −450.7 °F), and good flexibility at temperatures above 194 K (−79.15 °C; −110.5 °F). PTFE gains its properties from the aggregate effect of carbon-fluorine bonds , as do all fluorocarbons. The only chemicals known to affect these carbon-fluorine bonds are highly reactive metals like

222-526: A great and undeveloped potential to contribute value to society." Multi-Tet cable was the breakout product for the new company. Bob Gore was listed as the inventor when W. L. Gore & Associates registered its first patent in 1958, for what was then called "Multiconductor Wiring Strip". Multi-tet cable was eventually used in the IBM System/360 and other computers and in communications and process control equipment. The company provided cables for

296-403: A grooved calender roll, then heated to melt the tape into a coherent coating. The result was a PTFE-insulated ribbon cable containing multiple copper conductors, later called "Multi-Tet Cable". Solution of this technical problem was significant, and enabled Gore's parents, Bill and Genevieve, to create W. L. Gore & Associates in 1958. For the first two years, the business was run out of

370-591: A material to coat valves and seals in the pipes holding highly reactive uranium hexafluoride at the vast K-25 uranium enrichment plant in Oak Ridge, Tennessee . In 1954, Colette Grégoire urged her husband, the French engineer Marc Grégoire, to try the material he had been using on fishing tackle on her cooking pans. He subsequently created the first PTFE-coated, non-stick pans under the brand name Tefal (combining "Tef" from "Teflon" and "al" from aluminium). In

444-401: A membrane for blood oxygenation for Baxter International . Creating Gore-Tex tubes for use as vascular grafts was another area of rapid development. Gore-Tex is particularly useful internally in medical applications because it is nearly inert inside the body. In addition, the porosity of Gore-Tex permits the body's own tissue to grow through the material, integrating grafted material into

518-645: A minimal loss of performance over the lifetime of the gasket. PTFE is an ultraviolet (UV) transparent polymer. However, when exposed to an excimer laser beam it severely degrades due to heterogeneous photothermal effect . Processing PTFE can be difficult and expensive because its high melting temperature, 327 °C (621 °F), is above its decomposition temperature. Even when molten, PTFE does not flow due to its exceedingly high melt-viscosity. The viscosity and melting point can be decreased by inclusion of small amount of comonomers such as perfluoro (propylvinyl ether) and hexafluoropropylene (HFP). These cause

592-404: A research associate. In 1967, he became the company's technical and research leader. In 1969, Gore was researching a process for stretching extruded PTFE into pipe thread tape when he discovered that the polymer could be "expanded" into a porous form of PTFE, characterized by extremely high strength and porosity. He and others had attempted to stretch rods of PTFE by about 10%. His discovery of

666-467: A result, moisture from rain or snow cannot penetrate the fabric, while perspiration can escape as it evaporates. The first report of using Gore-Tex to make waterproof, breathable garments appeared in a market report, April 13, 1972. The manufacturing process was patented in 1972. The first commercial sales of Gore-Tex were made in 1976 when Early Winters, Ltd., began making and selling Gore-Tex tents. The next year Early sold Gore-Tex rainwear. Gore-Tex

740-583: A single mass. The most common use of PTFE, consuming about 50% of production, is for the insulation of wiring in aerospace and computer applications (e.g. hookup wire, coaxial cables). This application exploits the fact that PTFE has excellent dielectric properties, specifically low group velocity dispersion , especially at high radio frequencies , making it suitable for use as an excellent insulator in connector assemblies and cables , and in printed circuit boards used at microwave frequencies. Combined with its high melting temperature, this makes PTFE

814-517: A subject of study. In 2000, Gore stepped down as president, becoming chairman, a position he held until 2016. Gore married his third wife Sarah Louise "Sally" (née Ives) Coons in late 1977. Gore died on September 17, 2020, in Earleville, Maryland . A major focus of philanthropy for Gore was his alma maters, the University of Delaware and the University of Minnesota. He served on

SECTION 10

#1732793711653

888-401: A surfactant is the primary means of keeping PTFE in an aqueous medium. Surfactants in the past have included toxic perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS). More recently, Perfluoro 3,6 dioxaoctanoic acid (PFO2OA) and FRD-903 (GenX) are being used as alternative surfactants. PTFE is a thermoplastic polymer , which is a white solid at room temperature, with

962-406: A weight differential in his test cylinder, brought it to the attention of Roy Plunkett. The chemists in the lab sawed the bottle apart and found the bottle's interior coated with a waxy white material that was oddly slippery. Analysis showed that it was polymerized perfluoroethylene, with the iron from the inside of the container having acted as a catalyst at high pressure. Kinetic Chemicals patented

1036-433: Is hydrophobic : neither water nor water-containing substances wet PTFE, as fluorocarbons exhibit only small London dispersion forces due to the low electric polarizability of fluorine. PTFE has one of the lowest coefficients of friction of any solid. Polytetrafluoroethylene is used as a non-stick coating for pans and other cookware. It is non-reactive, partly because of the strength of carbon–fluorine bonds , so it

1110-535: Is a brand of expanded PTFE (ePTFE), a material incorporating a fluoropolymer membrane with micropores. The roof of the Hubert H. Humphrey Metrodome in Minneapolis , US, was one of the largest applications of PTFE coatings. 20 acres (81,000 m ) of the material was used in the creation of the white double-layered PTFE-coated fiberglass dome. Because of its extreme non-reactivity and high temperature rating, PTFE

1184-430: Is a synthetic fluoropolymer of tetrafluoroethylene , and has numerous applications because it is chemically inert . The commonly known brand name of PTFE-based composition is Teflon by Chemours , a spin-off from DuPont , which originally discovered the compound in 1938. Polytetrafluoroethylene is a fluorocarbon solid, as it is a high- molecular-weight polymer consisting wholly of carbon and fluorine . PTFE

1258-586: Is considered a minor exposure pathway to PFOA. As a result of the lawsuits concerning the PFOA class-action lawsuit , DuPont began to use GenX, a similarly fluorinated compound, as a replacement for perfluorooctanoic acid in the manufacture of fluoropolymers , such as Teflon-brand PTFE. However, the EPA has classified GenX as more toxic than PFOA and it has proven to be a “regrettable substitute”; its effects may be equally harmful or even more detrimental than those of

1332-907: Is no longer being made in the United States. PTFE was added to the Living Building Challenge (LBC) Red List in 2016. The Red List bans substances prevalent in the building industry that pose serious risks to human health and the environment from construction that seeks to meet the criteria of the Living Building Challenge (LBC). Sodium trifluoroacetate and the similar compound sodium chlorodifluoroacetate can both be generated when PTFE undergoes thermolysis , as well as producing longer chain polyfluoro- and/or polychlorofluoro- (C3-C14) carboxylic acids which may be equally persistent. These products can accumulate in evaporative wetlands and have been found in

1406-501: Is nominated, the chair of the committee then notifies the prospective awardee of his/her nomination and the requirements for receiving the medal. If the prospective awardee accepts the nomination, the medal is presented to the nominee at the Chemists’ Club’s annual Egg Nog Gala where they deliver a brief address and accept the award. If the nominee rejects the award, the nominating committee then nominates their second choice nominee for

1480-568: Is notable for its extremely low coefficient of friction, its hydrophobia (which serves to inhibit rust), and for the dry film it forms after application, which allows it to resist collecting particles that might otherwise form an abrasive paste. Brands include GT85, Tri-Flow and WD-40 Specialist. PTFE is best known for its use in coating non-stick frying pans and other cookware, as it is hydrophobic and possesses fairly high heat resistance. The sole plates of some clothes irons are coated with PTFE. Other niche applications include: While PTFE

1554-403: Is often used as the liner in hose assemblies, expansion joints , and in industrial pipe lines, particularly in applications using acids, alkalis, or other chemicals. Its frictionless qualities allow improved flow of highly viscous liquids and for uses in applications such as brake hoses. PTFE architectural membranes are created by coating a woven glass-fibre base cloth with PTFE, forming one of

SECTION 20

#1732793711653

1628-669: Is often used in containers and pipework for reactive and corrosive chemicals. Where used as a lubricant , PTFE reduces friction, wear, and energy consumption of machinery. It is used as a graft material in surgery and as a coating on catheters . PTFE and chemicals used in its production are some of the best-known and widely applied PFAS , which are persistent organic pollutants . PTFE occupies more than half of all fluoropolymer production, followed by polyvinylidene fluoride (PVdF) . For decades, DuPont used perfluorooctanoic acid (PFOA, or C8) during production of PTFE, later discontinuing its use due to legal actions over ecotoxicological and

1702-638: Is presented each December at The Chemists’ Club annual Egg Nog Gala held at the New York Academy of Sciences (previously presented in association with the Chemical Heritage Foundation during the Chemical Heritage Foundation’s Heritage Day activities, in the spring of each year). The medal was established in 1970 to recognize individuals who, by their entrepreneurial achievement, have contributed to

1776-439: Is stable at lower temperatures, it begins to deteriorate at temperatures of about 260 °C (500 °F), it decomposes above 350 °C (662 °F), and pyrolysis occurs at temperatures above 400 °C (752 °F). The main decomposition products are fluorocarbon gases and a sublimate , including tetrafluoroethylene (TFE) and difluorocarbene radicals (RCF2). An animal study conducted in 1955 concluded that it

1850-440: Is typically initiated with persulfate , which homolyzes to generate sulfate radicals: The resulting polymer is terminated with sulfate ester groups, which can be hydrolyzed to give OH end-groups . Granular PTFE is produced via suspension polymerization, where PTFE is suspended in an aqueous medium primarily via agitation and sometimes with the use of a surfactant. PTFE is also synthesized via emulsion polymerization, where

1924-532: Is typically placed between an outer fabric and an inner lining. The material allows moisture to pass easily from one layer through the next, a process known as wicking. This, and a polymer coating that increases the ability of the fabric to repel water, reduce the chance that the wearer will become damp, cold, or a victim of heat loss. In 1989, Gore began to license manufacturers to use the Gore-Tex material and label: however, products must survive rigorous testing in

1998-571: Is unlikely that these products would be generated in amounts significant to health at temperatures below 250 °C (482 °F). Above those temperatures the degradation by-products can be lethal to birds , and can cause flu-like symptoms in humans ( polymer fume fever ), although in humans those symptoms disappear within a day or two of being moved to fresh air. Most cases of polymer fume fever in humans occur due to smoking PTFE-contaminated tobacco, although cases have occurred in people who have welded near PTFE components. PTFE-coated cookware

2072-434: Is unlikely to reach dangerous temperatures with normal use, as meat is usually fried between 204 and 232 °C (399 and 450 °F), and most cooking oils (except refined safflower and avocado oils) start to smoke before a temperature of 260 °C (500 °F) is reached. A 1973 study by DuPont's Haskell Laboratory found that a 4-hour exposure to the fumes emitted by PTFE cookware heated to 280 °C (536 °F)

2146-500: Is usually measured against polished steel. PTFE's coefficient of friction is 0.05 to 0.10, which is the third-lowest of any known solid material ( aluminium magnesium boride (BAM) being the lowest, with a coefficient of friction of 0.02; diamond-like carbon being second-lowest at 0.05). PTFE's resistance to van der Waals forces means that it is the only known surface to which a gecko cannot stick. In addition, PTFE can be used to prevent insects from climbing up surfaces painted with

2220-766: The DuPont Experimental Station in Wilmington, Delaware . The Gore family stayed with friends for several months while Bob's father built their house. Bob attended school in Newark beginning in eighth grade. Gore graduated with a bachelor's degree in chemical engineering at the University of Delaware in 1959. With his wife and son, he moved to University Village in September 1959 to attend graduate school. He completed his graduate studies at

2294-422: The University of Minnesota , earning an MS and then a PhD in chemical engineering in 1963. While his father Bill Gore was working for DuPont, he was also experimenting at home with DuPont materials such as Teflon polytetrafluoroethylene (Teflon PTFE). He wanted to insulate electrical wires using PTFE, but attempts to coat wire with powdered PTFE did not produce a consistent coating. In April 1957, while Bob

Winthrop-Sears Medal - Misplaced Pages Continue

2368-476: The alkali metals , at higher temperatures such metals as aluminium and magnesium, and fluorinating agents such as xenon difluoride and cobalt(III) fluoride . At temperatures above 650–700 °C (1,200–1,290 °F) PTFE undergoes depolymerization. However, it begins to decompose at about 260 °C (500 °F) through 350 °C (662 °F), and pyrolysis occurs at temperatures above 400 °C (752 °F). The coefficient of friction of plastics

2442-460: The electrostatic analogues of permanent magnets . PTFE film is also widely used in the production of carbon fiber composites as well as fiberglass composites, notably in the aerospace industry. PTFE film is used as a barrier between the carbon or fiberglass part being built and, in breather and bagging materials, is used to incapsulate the bondment when debulking (vacuum removal of air from between layers of laid-up plies of material) and when curing

2516-438: The health effects of exposure to PFOA . Dupont's spin-off Chemours today manufactures PTFE using an alternative chemical it calls GenX , another PFAS. Although GenX was designed to be less persistent in the environment compared to PFOA, it has proven to be a “regrettable substitute.” Its effects may be equally harmful or even more detrimental than those of the chemical it was meant to replace. Polytetrafluoroethylene (PTFE)

2590-429: The 1990s, PTFE was not known to crosslink like an elastomer , due to its chemical inertness. Therefore, it has no "memory" and is subject to creep . Because of the propensity to creep, the long-term performance of such seals is worse than for elastomers that exhibit zero, or near-zero, levels of creep. In critical applications, Belleville washers are often used to apply continuous force to PTFE gaskets, thereby ensuring

2664-537: The 1990s, it was found that PTFE could be radiation cross-linked above its melting point in an oxygen-free environment. Electron beam processing is one example of radiation processing. Cross-linked PTFE has improved high-temperature mechanical properties and radiation stability. That was significant because, for many years, irradiation at ambient conditions has been used to break down PTFE for recycling. This radiation-induced chain scission allows it to be more easily reground and reused. Corona discharge treatment of

2738-765: The Club and all were nurtured there as their memberships entirely overlapped with our Club. The modern practice of honoring great accomplishments in chemistry originated simultaneously in Berlin and New York in 1903 when the Association of German Chemists and the German Chemical Society instituted both the Liebig Medal and the August Wilhelm von Hofmann Medal while The Chemists’ Club instituted

2812-539: The Gore company's rain room, abrasion tests and washing machines to be authorized for market release. Gore became president and CEO of the company in 1976, replacing his father. The company retained its base in Newark, Delaware, but expanded worldwide. Ongoing work has developed Gore's initial ideas and resulted in four main areas of focus for the company: divisions for fabrics, medical, industrial, and electronic products. The organization's innovative managerial style has been

2886-616: The Nichols Medal and, in 1906, the Perkin Medal. Traditionally The Chemists’ Club facilitated and hosted these celebrations while one of The Sisters awarded the medals. This arrangement continued for over a half century when, in 1970, The Club initiated The Winthrop-Sears Medal. This medal was named after two very early chemical industry pioneers, one of whom was John Winthrop the Younger, one of America’s earliest scientists who

2960-667: The President of the Chemists’ Club, one Past President of The Chemists’ Club, and two other members of The Chemists’ Club Board of Trustees, at minimum. The President selects the chair of the committee and may also name other participants to the committee who need not be members of The Chemists’ Club as well (the committee has previously included representatives from Societe de Chimie (America’s Section), SOCMA, and other industry affiliates/partners). The nominating committee members each submit names of candidates whom they consider worthy of

3034-654: The Surveyor satellites and Apollo space craft. During the Apollo 11 space mission, astronauts used a Gore cable to connect their ship to a seismograph placed on the surface of the Moon. Bob Gore was elected to the board of directors of W. L. Gore & Associates in June 1961, while still a student at the University of Minnesota. After receiving his PhD in chemical engineering in 1963, Gore joined W. L. Gore & Associates as

Winthrop-Sears Medal - Misplaced Pages Continue

3108-855: The US, there were seven chemical societies, known as the Seven Sisters and The Chemists’ Club was alma mater to all of them: American sections of the Society of Chemical Industry, Verein Deutscher Chemiker and Société de Chimie Industrielle, and the American Chemical Society, the American Institute of Chemists, American Institute of Chemical Engineers, and Electrochemical Society; many of the Sisters were born at

3182-410: The United States, Marion A. Trozzolo , who had been using the substance on scientific utensils, marketed the first US-made PTFE-coated pan, "The Happy Pan", in 1961. Non-stick cookware has since become a common household product, now offered by hundreds of manufacturers across the world. The brand name Zepel was used for promoting its stain-resistance and water-resistance when applied to fabrics. In

3256-518: The Winthrop-Sears medal and the nominating committee members then come to a consensus on a prospective awardee. The prospective awardees are evaluated based on the impact of their contribution to the vitality of the chemical industry and the betterment of humanity over the past year, and their journey to their entrepreneurial achievement. Prospective awardees are not limited to c-suite professionals or chemistry-specific employees. Once an awardee

3330-643: The area beginning in 1976 with the production of Nafion, and that PFAS including GenX had been released as a byproduct of the production of Vinyl Ethers since 1980, exposing the Cape Fear Basin for decades. A small nonprofit called Cape Fear River Watch sued NC DEQ for not taking swifter and stronger action, and sued the polluter, Chemours, for violations of the Clean Water Act and the Toxic Substances Control Act. The result

3404-632: The award and repeats the nominee notification process. The remainder of the top three candidates selected by the nominating committee for the Winthrop-Sears medal that had not received the medal in the current year remain candidates for the medal for the following two years. Source (2004–10): Robert W. Gore Robert W. Gore (April 15, 1937 – September 17, 2020) was an American engineer and scientist, inventor and businessman. Gore led his family's company, W. L. Gore & Associates , in developing applications of polytetrafluoroethylene (PTFE) ranging from computer cables to medical equipment to

3478-425: The basement of the Gore home. Robert Gore lived upstairs with his parents, other family members, and employees of the company. At one point 13 of the 16 people working for the company lived in the Gore home. As stated in a 1960 brochure, the company "was established for the purpose of developing and utilizing technology in the field of fluorocarbon polymers, especially polytetrafluoroethylene", materials which "have

3552-461: The blood of people who work in or live near factories where the chemical is used, and in people regularly exposed to PFOA-containing products such as some ski waxes and stain-resistant fabric coatings, but non-stick cookware was not found to be a major source of exposure, as the PFOA is burned off during the manufacturing process and not present in the finished product. Non-stick coated cookware has not been manufactured using PFOA since 2013, and PFOA

3626-560: The board of trustees as an emeritus member from 1992 to 2010 and as vice chairman from 1999 to 2007. He and other members of the Gore family have made a number of gifts to Delaware. These include: Gore was elected to the National Academy of Engineering in 1995 for his technical achievements. In 2003, Gore was awarded the Winthrop-Sears Medal in recognition of "entrepreneurial achievement that contributes to

3700-648: The chemical it was meant to replace. The chemicals are manufactured by Chemours , a corporate spin-off of DuPont, in Fayetteville, North Carolina . Fayetteville Works was the site where DuPont began manufacture of PFOA after the lawsuit in Parkersburg WV halted their production there. When EPA asked companies to voluntarily phase out PFOA production, it was replaced by GenX in Fayetteville Works. In June of 2017, The Wilmington Star-News broke

3774-435: The circulation system. More popularly, Gore-Tex is known for its use as a waterproof, breathable fabric, used in outdoor clothing and sport footwear. To the human eye, it looks and feels like a smooth fabric. Structurally, the membrane of the fabric contains about nine-billion microscopic pores per square inch. The holes are large enough to allow body heat and water vapour to escape, but small enough to deflect water drops. As

SECTION 50

#1732793711653

3848-424: The composite, usually in an autoclave. The PTFE, used here as a film, prevents the non-production materials from sticking to the part being built, which is sticky due to the carbon-graphite or fiberglass plies being pre-pregnated with bismaleimide resin. Non-production materials such as Teflon, Airweave Breather, and the bag itself would be considered F.O.D. (foreign object debris/damage) if left in layup. Gore-Tex

3922-563: The end of the production and phase out of PFOA and PFOS in the US. The general population has been exposed to PFOA through massive dumping of C8 waste into the ocean and near the Ohio River Valley. PFOA has been detected in industrial waste, stain-resistant carpets, carpet cleaning liquids, house dust , microwave popcorn bags , water, food and PTFE cookware. As a result of a class-action lawsuit and community settlement with DuPont , three epidemiologists conducted studies on

3996-418: The general US population in the low and sub- parts per billion range, and levels are higher in chemical plant employees and surrounding subpopulations. PFOA and perfluorooctanesulfonic acid (PFOS) have been estimated to be in every American person's blood stream in the parts per billion range, though those concentrations have decreased by 70% for PFOA and 84% for PFOS between 1999 and 2014, which coincides with

4070-514: The material of choice as a high-performance substitute for the weaker, higher dispersion and lower-melting-point polyethylene commonly used in low-cost applications. In industrial applications, owing to its low friction, PTFE is used for plain bearings , gears , slide plates , seals, gaskets, bushings, and more applications with sliding action of parts, where it outperforms acetal and nylon . Its extremely high bulk resistivity makes it an ideal material for fabricating long-life electrets ,

4144-411: The material. For example, PTFE is used to prevent ants from climbing out of formicaria . There are surface treatments for PTFE that alter the surface to allow adhesion to other materials. Because of its chemical and thermal properties, PTFE is often used as a gasket material within industries that require resistance to aggressive chemicals such as pharmaceuticals or chemical processing. However, until

4218-587: The new fluorinated plastic (analogous to the already known polyethylene ) in 1941, and registered the Teflon trademark in 1945. By 1948, DuPont, which founded Kinetic Chemicals in partnership with General Motors , was producing over 910,000 kilograms (2,000,000 lb) of Teflon-brand polytetrafluoroethylene per year in Parkersburg, West Virginia . An early use was in the Manhattan Project as

4292-424: The otherwise perfectly linear PTFE chain to become branched, reducing its crystallinity. Some PTFE parts are made by cold-moulding, a form of compression molding . Here, fine powdered PTFE is forced into a mould under high pressure (10–100 MPa). After a settling period, lasting from minutes to days, the mould is heated at 360 to 380 °C (680 to 716 °F), allowing the fine particles to fuse ( sinter ) into

4366-472: The outer layer of space suits. His most significant breakthrough was likely the invention of Gore-Tex , a waterproof and breathable fabric popularly known for its use in sporting and outdoor gear. Robert Gore was born in Salt Lake City, Utah on April 15, 1937, to Wilbert "Bill" and Genevieve "Vieve" Gore. His family relocated to near Newark, Delaware in 1950, to be near his father's work at

4440-500: The population of Parkersburg, WV surrounding the (former DuPont) Chemours Washington Works chemical plant that was exposed to PFOA at levels greater than in the general population. The studies concluded that there was an association between PFOA exposure and six health outcomes: kidney cancer , testicular cancer , ulcerative colitis , thyroid disease , hypercholesterolemia (high cholesterol), and gestational hypertension (pregnancy-induced high blood pressure). Overall, PTFE cookware

4514-533: The product, and another for the processes for making the product. Gore continued to investigate the properties of the new material, studying the effectiveness of different PTFE resins. He also worked with others to develop techniques for stretching the material both one-dimensionally, to create long filaments, and two-dimensionally, to create sheets of the membrane. Two-dimensional stretching created sheets with greater strength, porosity, and air flow, opening up possibilities for many new applications. By 1971, Gore

SECTION 60

#1732793711653

4588-413: The right conditions for stretching PTFE was a happy accident, born partly of frustration. Instead of slowly stretching the heated material, he applied a sudden, accelerating yank. The solid PTFE unexpectedly stretched about 800%, forming a microporous structure that was about 70% air. A patent application for expanded PTFE was filed on May 21, 1970, and eventually two separate patents were issued, one for

4662-427: The roots and seeds of wetland plant species, but has not been observed to have an adverse impact on plant health or germination success. Perfluorooctanoic acid (PFOA, or C8) has been used as a surfactant in the emulsion polymerization of PTFE, although several manufacturers have entirely discontinued its use. PFOA persists indefinitely in the environment. PFOA has been detected in the blood of many individuals of

4736-593: The story that GenX was found in the Cape Fear River – the drinking water supply for 500,000 people. The source of the pollution was determined to be the Fayetteville Works site, which had been run by DuPont since its founding in 1971 and then managed by DuPont spinoff, The Chemours Company, since 2015. The water utility confirmed they had no ability to filter these chemicals from the drinking water. The North Carolina Department of Environmental Quality (NC DEQ) records indicate that DuPont started release PFAS into

4810-784: The strongest and most durable materials used in tensile structures . Some notable structures featuring PTFE-tensioned membranes include The O2 Arena in London, Moses Mabhida Stadium in South Africa, Metropolitano Stadium in Spain and the Sydney Football Stadium Roof in Australia. PTFE is often found in musical instrument lubrication products, most commonly valve oil. PTFE is used in some aerosol lubricant sprays, including in micronized and polarized form. It

4884-485: The surface to increase the energy and improve adhesion has been reported. PTFE is produced by free-radical polymerization of tetrafluoroethylene . The net equation is Because tetrafluoroethylene can explosively decompose to tetrafluoromethane ( CF 4 {\textstyle {\ce {CF4}}} ) and carbon, a special apparatus is required for the polymerization to prevent hot spots that might initiate this dangerous side reaction. The process

4958-681: The vitality of the chemical industry and the betterment of humanity. The medal is named in honor of two of America’s earliest chemical entrepreneurs, John Winthrop, Jr., son of the first Governor of the Massachusetts Bay Colony and considered the first chemist in America, and John Sears, creator of the Massachusetts salt industry. The recipient of the Winthrop-Sears medal is chosen through the Chemists’ Club’s designated nominating committee. The nominating committee consists of

5032-725: The vitality of the chemical industry and the betterment of mankind". In 2005, he received the Perkin Medal , awarded for "contributions to the improvement of the quality of life and the world competitiveness of the U.S. economy". In recognition of his work in developing Gore-Tex, Gore was inducted into the American National Inventors Hall of Fame in 2006. Gore received an honorary doctorate from Heriot-Watt University in 2001. Gore held nine patents for his work with fluoropolymers. Polytetrafluoroethylene Polytetrafluoroethylene ( PTFE )

5106-465: Was a Consent Order, signed February 25, 2019 by Cape Fear River Watch, NC DEQ, and Chemours. The order has required Chemours to stop wastewater discharge, air emissions, groundwater discharge, sampling and filtration options to well users, and required sampling that proved there were upwards of 300 distinct PFAS compounds being released from Fayetteville Works. The Teflon trade name is also used for other polymers with similar compositions: These retain

5180-539: Was accidentally discovered in 1938 by Roy J. Plunkett while he was working in Chemours Chambers Works plant in New Jersey for DuPont . A team of Dupont chemists attempted to make a new chlorofluorocarbon refrigerant, called tetrafluoroethylene . The gas in its pressure bottle stopped flowing before the bottle's weight had dropped to the point signaling "empty". John J. Beall (chemist), noticing

5254-609: Was elected Fellow of the Royal Society in 1662. He is also considered the Father of Connecticut because he convinced the British government to unite Saybrook, New Haven and River Colonies into a combined Connecticut Colony and then became popular Colonial Governor for many years. The Winthrop-Sears Medal for Entrepreneurial Achievement recognized entrepreneurship that revitalized the chemical industry and betters humanity. The medal

5328-514: Was experimenting with laminates, combining the stretched membrane with supporting materials for added strength. Based on this work, the company developed a waterproof laminate called expanded polytetrafluoroethylene (ePTFE), now trademarked as Gore-Tex. Some of the company's earliest successful products, based on work with laminates, were burn bandages developed for the Park-Davis company, microfiltration products for Millipore Corporation , and

5402-423: Was lethal for parakeets , although that was a higher temperature than the 260 °C (500 °F) required for fumes from pyrolyzed butter to be lethal to the birds. Perfluorooctanoic acid (PFOA), a chemical formerly used in the manufacture of PTFE products such as non-stick coated cookware, can be carcinogenic for people who are exposed to it (see Ecotoxicity ). Concerning levels of PFOA have been found in

5476-452: Was still a sophomore at Delaware, Bill showed him around his home lab and explained the problem he was having. Bob suggested surrounding the wire with a different form of PTFE, a white tape that was already of uniform thickness. His father expected that the PTFE tape would not stick to the wire, but he tried the idea, and it worked. Wires were laid between layers of PTFE tape and sent through

#652347