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Some familiar household synthetic polymers include: Nylons in textiles and fabrics, Teflon in non-stick pans , Bakelite for electrical switches, polyvinyl chloride (PVC) in pipes, etc. The common PET bottles are made of a synthetic polymer, polyethylene terephthalate . The plastic kits and covers are mostly made of synthetic polymers like polythene , and tires are manufactured from polybutadienes . However, due to the environmental issues created by these synthetic polymers which are mostly non-biodegradable and often synthesized from petroleum, alternatives like bioplastics are also being considered. They are however expensive when compared to the synthetic polymers.

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49-454: Nylon is a family of synthetic polymers with amide backbones, usually linking aliphatic or semi-aromatic groups. Nylons are white or colorless and soft; some are silk -like. They are thermoplastic , which means that they can be melt-processed into fibers, films , and diverse shapes. The properties of nylons are often modified by blending with a wide variety of additives. Many kinds of nylon are known. One family, designated nylon-XY,

98-409: A dyadic homopolymer formed from two monomers: one diamine and one dicarboxylic acid. The first number indicates the number of carbons in the diamine. The two numbers should be separated by a comma for clarity, but the comma is often omitted. For copolymers the comonomers or pairs of comonomers are separated by slashes: The term polyphthalamide (abbreviated to PPA) is used when 60% or more moles of

147-564: A ring-opening polymerization . The peptide bond within the caprolactam is broken with the exposed active groups on each side being incorporated into two new bonds as the monomer becomes part of the polymer backbone. The 428 °F (220 °C) melting point of nylon 6 is lower than the 509 °F (265 °C) melting point of nylon 66 . Homopolymer nylons are derived from one monomer. Examples of these polymers that are or were commercially available: Nylons can also be synthesized from dinitriles using acid catalysis. For example, this method

196-471: A chemical extracted from corpses. Although scientists asserted that cadaverine was also extracted by heating coal, the public often refused to listen. A woman confronted one of the lead scientists at DuPont and refused to accept that the rumour was not true. DuPont changed its campaign strategy, emphasizing that nylon was made from "coal, air and water", and started focusing on the personal and aesthetic aspects of nylon, rather than its intrinsic qualities. Nylon

245-428: A diamine and a dicarboxylic acid, it is difficult to get the proportions exactly correct, and deviations can lead to chain termination at molecular weights less than a desirable 10,000 daltons . To overcome this problem, a crystalline , solid "nylon salt " can be formed at room temperature , using an exact 1:1 ratio of the acid and the base to neutralize each other. The salt is crystallized to purify it and obtain

294-453: A different molecule based on caprolactam , on January 29, 1938. In the spring of 1930, Carothers and his team had already synthesized two new polymers. One was neoprene , a synthetic rubber greatly used during World War II. The other was a white elastic but strong paste that would later become nylon. After these discoveries, Carothers' team was made to shift its research from a more pure research approach investigating general polymerization to

343-480: A more practically focused goal of finding "one chemical combination that would lend itself to industrial applications". It was not until the beginning of 1935 that a polymer called "polymer 6-6" was finally produced. Carothers' coworker, Washington University alumnus Julian W. Hill had used a cold drawing method to produce a polyester in 1930. This cold drawing method was later used by Carothers in 1935 to fully develop nylon. The first example of nylon (nylon 6.6)

392-494: A range of blends to be made. The two polymers can react with one another by transamidation to form random copolymers. According to their crystallinity, polyamides can be: According to this classification, PA66, for example, is an aliphatic semi-crystalline homopolyamide. All nylons are susceptible to hydrolysis , especially by strong acids , a reaction essentially the reverse of their synthesis. The molecular weight of nylon products so attacked drops, and cracks form quickly at

441-507: Is applicable for preparation of nylon 1,6 from adiponitrile , formaldehyde and water. Additionally, nylons can be synthesized from diols and dinitriles using this method as well. It is easy to make mixtures of the monomers or sets of monomers used to make nylons to obtain copolymers. This lowers crystallinity and can therefore lower the melting point. Some copolymers that have been or are commercially available are listed below: Most nylon polymers are miscible with each other allowing

490-590: Is derived from diamines and dicarboxylic acids of carbon chain lengths X and Y, respectively. An important example is nylon-6,6 (C₁₂H₂₂N₂O₂). Another family, designated nylon-Z, is derived from aminocarboxylic acids with carbon chain length Z. An example is nylon-[6]. Nylon polymers have significant commercial applications in fabric and fibers (apparel, flooring and rubber reinforcement), in shapes (molded parts for cars, electrical equipment, etc.), and in films (mostly for food packaging ). Researchers at DuPont began developing cellulose-based fibers, culminating in

539-415: Is estimated at 8.9 million tons. Although pure nylon has many flaws and is now rarely used, its derivatives have greatly influenced and contributed to society. From scientific discoveries relating to the production of plastics and polymerization, to economic impact during the depression and the changing of women's fashion, nylon was a revolutionary product. The Lunar Flag Assembly , the first flag planted on

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588-459: Is now capable of generating non-natural analogues of biopolymers that should be referred to as artificial biopolymers, e.g., artificial protein, artificial polynucleotide, etc. The eight most common types of synthetic organic polymers, which are commonly found in households are: These polymers are often better known through their brand names, for instance: [REDACTED] Stocking Too Many Requests If you report this error to

637-523: The Army and Navy , had committed to developing a wool-nylon blend. They were not the only ones to introduce blends of both natural and synthetic fibers. America's Textile Reporter referred to 1951 as the "Year of the blending of the fibers". Fabric blends included mixes like "Bunara" (wool-rabbit-nylon) and "Casmet" (wool-nylon-fur). In Britain, in November 1951, the inaugural address of the 198th session of

686-404: The 1970s". Also, consumers became concerned about environmental costs throughout the production cycle: obtaining the raw materials (oil), energy use during production, waste produced during creation of the fiber, and eventual waste disposal of materials that were not biodegradable. Synthetic fibers have not dominated the market since the 1950s and 1960s. As of 2020, the worldwide production of nylon

735-455: The 1970s, it became more popular due to its flexibility and price. In spite of oil shortages in the 1970s, consumption of nylon textiles continued to grow by 7.5% per year between the 1960s and 1980s. Overall production of synthetic fibers, however, dropped from 63% of the worlds textile production in 1965, to 45% of the world's textile production in early 1970s. The appeal of "new" technologies wore off, and nylon fabric "was going out of style in

784-685: The Department of Rayon. Some of the key ingredients of nylon had to be produced using high pressure chemistry , the main area of expertise of the Ammonia Department. Nylon was considered a "godsend to the Ammonia Department", which had been in financial difficulties. The reactants of nylon soon constituted half of the Ammonia Department's sales and helped them come out of the period of the Great Depression by creating jobs and revenue at DuPont. DuPont's nylon project demonstrated

833-841: The Royal Society for the Encouragement of Arts, Manufactures and Commerce focused on the blending of textiles. DuPont's Fabric Development Department cleverly targeted French fashion designers, supplying them with fabric samples. In 1955, designers such as Coco Chanel , Jean Patou , and Christian Dior showed gowns created with DuPont fibers, and fashion photographer Horst P. Horst was hired to document their use of DuPont fabrics. American Fabrics credited blends with providing "creative possibilities and new ideas for fashions which had been hitherto undreamed of." DuPont went through an extensive process to generate names for its new product. In 1940, John W. Eckelberry of DuPont stated that

882-407: The affected zones. Lower members of the nylons (such as nylon 6) are affected more than higher members such as nylon 12. This means that nylon parts cannot be used in contact with sulfuric acid for example, such as the electrolyte used in lead–acid batteries . When being molded, nylon must be dried to prevent hydrolysis in the molding machine barrel since water at high temperatures can also degrade

931-406: The announcement of nylon, therefore he was never able to see his success. Nylon was first used commercially in a nylon- bristled toothbrush in 1938, followed more famously in women's stockings or "nylons" which were shown at the 1939 New York World's Fair and first sold commercially in 1940, whereupon they became an instant commercial success with 64 million pairs sold during their first year on

980-493: The carboxylic acid portion of the repeating unit in the polymer chain is composed of a combination of terephthalic acid (TPA) and isophthalic acid (IPA). Nylon 66 and related polyamides are condensation polymers forms from equal parts of diamine and dicarboxylic acids . In the first case, the "repeating unit" has the ABAB structure, as also seen in many polyesters and polyurethanes . Since each monomer in this copolymer has

1029-459: The chemical department would be composed of several small research teams that would focus on "pioneering research" in chemistry and would "lead to practical applications". Harvard instructor Wallace Hume Carothers was hired to direct the polymer research group. Initially he was allowed to focus on pure research, building on and testing the theories of German chemist Hermann Staudinger . He was very successful, as research he undertook greatly improved

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1078-406: The civilian demand, and continually expanded its production. As pure nylon hosiery was sold in a wider market, problems became apparent. Nylon stockings were found to be fragile, in the sense that the thread often tended to unravel lengthwise, creating 'runs'. People also reported that pure nylon textiles could be uncomfortable due to nylon's lack of absorbency. Moisture stayed inside the fabric near

1127-501: The demand for nylon stockings could not be satisfied, which led to the nylon riots . In one instance, an estimated 40,000 people lined up in Pittsburgh to buy 13,000 pairs of nylons. In the meantime, women cut up nylon tents and parachutes left from the war in order to make blouses and wedding dresses. Between the end of the war and 1952, production of stockings and lingerie used 80% of the world's nylon. DuPont put focus on catering to

1176-479: The desired precise stoichiometry. Heated to 285 °C (545 °F), the salt reacts to form nylon polymer with the production of water. Nylon 510, made from pentamethylene diamine and sebacic acid, was included in the Carothers patent to nylon 66 Nylon 610 is produced similarly using hexamethylene diamine. These materials are more expensive because of the relatively high cost of sebacic acid. Owing to

1225-407: The high hydrocarbon content, nylon 610 is more hydrophobic and finds applications suited for this property, such as bristles. Examples of these polymers that are or were commercially available: These polymers are made from a lactam or amino acid. The synthetic route using lactams (cyclic amides) was developed by Paul Schlack at IG Farben , leading to nylon 6, or polycaprolactam —formed by

1274-406: The importance of chemical engineering in industry, helped create jobs, and furthered the advancement of chemical engineering techniques. In fact, it developed a chemical plant that provided 1800 jobs and used the latest technologies of the time, which are still used as a model for chemical plants today. The ability to acquire a large number of chemists and engineers quickly was a huge contribution to

1323-411: The knee, closing the decade just as it started off". The shorter skirts were accompanied by a demand for stockings that offered fuller coverage without the use of garters to hold them up. However, as of February 11, 1942, nylon production was redirected from being a consumer material to one used by the military. DuPont's production of nylon stockings and other lingerie stopped, and most manufactured nylon

1372-510: The knowledge of polymers and contributed to the science. Nylon was the first commercially successful synthetic thermoplastic polymer. DuPont began its research project in 1927. The first nylon, nylon 66 , was synthesized on February 28, 1935, by Wallace Hume Carothers at DuPont's research facility at the DuPont Experimental Station . In response to Carothers' work, Paul Schlack at IG Farben developed nylon 6 ,

1421-439: The letters "nyl" were arbitrary, and the "on" was copied from the suffixes of other fibers such as cotton and rayon . A later publication by DuPont ( Context , vol. 7, no. 2, 1978) explained that the name was originally intended to be "No-Run" ("run" meaning "unravel") but was modified to avoid making such an unjustified claim. Since the products were not really run-proof, the vowels were swapped to produce "nuron", which

1470-478: The market, an astounding 64 million pairs of nylon stockings were sold, reflecting the fabric's rapid integration into daily life and fashion.[8]: 101  Such was the success of nylon that in 1941, just a year after its launch, a second plant was opened in Martinsville, Virginia, to meet the growing demand and ensure a steady supply of this popular fabric. This expansion underscored the profound impact nylon had on

1519-399: The market. During World War II, almost all nylon production was diverted to the military for use in parachutes and parachute cord . Wartime uses of nylon and other plastics greatly increased the market for the new materials. The production of nylon required interdepartmental collaboration between three departments at DuPont: the Department of Chemical Research, the Ammonia Department, and

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1568-494: The moon in a symbolic gesture of celebration, was made of nylon. The flag itself cost $ 5.50 but had to have a specially designed flagpole with a horizontal bar so that it would appear to "fly". One historian describes nylon as "an object of desire", comparing the invention to Coca-Cola in the eyes of 20th century consumers. In common usage, the prefix "PA" ( polyamide ) or the name "Nylon" are used interchangeably and are equivalent in meaning. The nomenclature used for nylon polymers

1617-551: The national market until May 15, 1940. However, a limited number were released for sale in Delaware before that. The first public sale of nylon stockings occurred on October 24, 1939, in Wilmington, Delaware. 4,000 pairs of stockings were available, all of which were sold within three hours. Another added bonus to the campaign was that it meant reducing silk imports from Japan, an argument that won over many wary customers. Nylon

1666-434: The polymer. The reaction is shown above. Synthetic polymer Artificial polymer: Man-made polymer that is not a biopolymer . Note 1: Artificial polymer should also be used in the case of chemically modified biopolymers. Note 2: Biochemists are now capable of synthesizing copies of biopolymers that should be named Synthetic biopolymer to make a distinction with true biopolymers. Note 3: Genetic engineering

1715-461: The product was available to the general market. Nylon's commercial announcement occurred on October 27, 1938, at the final session of the Herald Tribune ' s yearly "Forum on Current Problems", on the site of the approaching New York City world's fair. The "first man-made organic textile fiber" which was derived from "coal, water and air" and promised to be "as strong as steel, as fine as

1764-415: The same reactive group on both ends, the direction of the amide bond reverses between each monomer, unlike natural polyamide proteins , which have overall directionality: C terminal  → N terminal . In the second case (so called AA), the repeating unit corresponds to the single monomer. Wallace Carothers at DuPont patented nylon 66 . In the case of nylons that involve reaction of

1813-595: The skin under hot or moist conditions instead of being "wicked" away. Nylon fabric could also be itchy and tended to cling and sometimes spark as a result of static electrical charge built up by friction. Also, under some conditions, stockings could decompose turning back into nylon's original components of air, coal, and water. Scientists explained this as a result of air pollution, attributing it to London smog in 1952, as well as poor air quality in New York and Los Angeles. The solution found to problems with pure nylon fabric

1862-578: The spider's web" was received enthusiastically by the audience, many of them middle-class women, and made the headlines of most newspapers. Nylon was introduced as part of "The world of tomorrow" at the 1939 New York World's Fair and was featured at DuPont's "Wonder World of Chemistry" at the Golden Gate International Exposition in San Francisco in 1939. Actual nylon stockings were not shipped to selected stores in

1911-545: The success of DuPont's nylon project. The first nylon plant was located at Seaford, Delaware, beginning commercial production on December 15, 1939. On October 26, 1995, the Seaford plant was designated a National Historic Chemical Landmark by the American Chemical Society . An important part of nylon's popularity stems from DuPont's marketing strategy. DuPont promoted the fiber to increase demand before

1960-456: The synthetic fiber rayon . DuPont's experience with rayon was an important precursor to its development and marketing of nylon. DuPont's invention of nylon spanned an eleven-year period, ranging from the initial research program in polymers in 1927 to its announcement in 1938, shortly before the opening of the 1939 New York World's Fair . The project grew from a new organizational structure at DuPont, suggested by Charles Stine in 1927, in which

2009-506: The terms of the original announcement, especially those stating that nylon would possess the strength of steel. Also, DuPont executives marketing nylon as a revolutionary man-made material did not at first realize that some consumers experienced a sense of unease and distrust, even fear, towards synthetic fabrics. A particularly damaging news story, drawing on DuPont's 1938 patent for the new polymer, suggested that one method of producing nylon might be to use cadaverine (pentamethylenediamine),

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2058-458: The textile industry and its rapid rise to prominence as a versatile and sought-after material. While nylon was marketed as the durable and indestructible material of the people, it was sold at about one-and-a-half times the price of silk stockings ($ 4.27 per pound of nylon versus $ 2.79 per pound of silk). Sales of nylon stockings were strong in part due to changes in women's fashion. As Lauren Olds explains: "by 1939 [hemlines] had inched back up to

2107-454: Was changed to "nilon" "to make it sound less like a nerve tonic". For clarity in pronunciation, the "i" was changed to "y". A persistent urban legend exists that the name is derived from "New York" and "London"; however, no organisation in London was ever involved in the research and production of nylon. Nylon’s popularity soared in the 1940s and 1950s due to its durability and sheerness. In

2156-463: Was devised during the synthesis of the first simple aliphatic nylons and uses numbers to describe the number of carbons in each monomer unit, including the carbon(s) of the carboxylic acid(s). Subsequent use of cyclic and aromatic monomers required the use of letters or sets of letters. One number after "PA" or "Nylon" indicates a homopolymer which is monadic or based on one amino acid (minus H 2 O) as monomer: Two numbers or sets of letters indicate

2205-500: Was even mentioned by President Roosevelt 's cabinet, which addressed its "vast and interesting economic possibilities" five days after the material was formally announced. However, the early excitement over nylon also caused problems. It fueled unreasonable expectations that nylon would be better than silk, a miracle fabric as strong as steel that would last forever and never run. Realizing the danger of claims such as "New Hosiery Held Strong as Steel" and "No More Runs", DuPont scaled back

2254-564: Was produced on February 28, 1935, at DuPont's research facility at the DuPont Experimental Station. It had all the desired properties of elasticity and strength. However, it also required a complex manufacturing process that would become the basis of industrial production in the future. DuPont obtained a patent for the polymer in September 1938, and quickly achieved a monopoly of the fiber. Carothers died 16 months before

2303-505: Was thus domesticated, and attention shifted to the material and consumer aspect of the fiber with slogans like "If it's nylon, it's prettier, and oh! How fast it dries!". After nylon's nationwide release in 1940, its production ramped up significantly. In that year alone, 1300 tons of the fabric were produced, marking a remarkable start for this innovative material.[8]: 100  The demand for nylon surged, particularly for nylon stockings, which became an instant sensation. During their first year on

2352-528: Was to blend nylon with other existing fibers or polymers such as cotton , polyester , and spandex . This led to the development of a wide array of blended fabrics. The new nylon blends retained the desirable properties of nylon (elasticity, durability, ability to be dyed) and kept clothes prices low and affordable. As of 1950, the New York Quartermaster Procurement Agency (NYQMPA), which developed and tested textiles for

2401-443: Was used to make parachutes and tents for World War II . Although nylon stockings already made before the war could be purchased, they were generally sold on the black market for as high as $ 20. Once the war ended, the return of nylon was awaited with great anticipation. Although DuPont projected yearly production of 360 million pairs of stockings, there were delays in converting back to consumer rather than wartime production. In 1946,

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