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- A polyamide is a polymer made of amides which are joined by peptide bonds. Examples for polyamides that occur naturally are proteins, such as wool and silk. It is also possible to artificially produce polyamides, one growth-step at a time. Examples for artificially-made polyamides are nylons, aramids and Sodium poly (aspartate).
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A polyamide is a polymer with repeating units linked by amide bonds. [1] Polyamides occur both naturally and artificially. Examples of naturally occurring polyamides are proteins, such as wool and silk.
- Polyamide-imide - Wikipedia
Polyamide-imides are either thermosetting or thermoplastic,...
- Polyamide - Simple English Wikipedia, the free encyclopedia
A polyamide is a polymer made of amides which are joined by...
- Polyamide-imide - Wikipedia
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A polyamide is a polymer made of amides which are joined by peptide bonds. Examples for polyamides that occur naturally are proteins, such as wool and silk. It is also possible to artificially produce polyamides, one growth-step at a time.
Polyamide, any polymer (substance composed of long, multiple-unit molecules) in which the repeating units in the molecular chain are linked together by amide groups. Amide groups have the general chemical formula CO-NH. They may be produced by the interaction of an amine (NH2) group and a carboxyl.
- The Editors of Encyclopaedia Britannica
Nylon 66 (loosely written nylon 6-6, nylon 6/6, nylon 6,6, or nylon 6:6) is a type of polyamide or nylon. It, and nylon 6, are the two most common for textile and plastic industries. Nylon 66 is made of two monomers each containing 6 carbon atoms, hexamethylenediamine and adipic acid, which give nylon 66 its name. [1]
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DuPont and the invention of nylon
Researchers at DuPont began developing cellulose-based fibers, culminating in the synthetic fiber rayon. DuPont's experience with rayon was an important precursor to its development and marketing of nylon.: 8, 64, 236 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, sug...
Early marketing strategies
An important part of nylon's popularity stems from DuPont's marketing strategy. DuPont promoted the fiber to increase demand before 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.: 141 The "first man-made organic textile fiber" which was derived from "coal, water and air" and promised to be "a...
Production of nylon fabric
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.: 100 The demand for nylon surged, particularly for nylon stockings, which became an instant sensation. During their first year on the market, an astounding 64 million pairs of nylon stockings were sold, reflecting the fabric's rapid integration into daily life and fashion.: 101 Such was the success...
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 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 aci...
Nylon 66 and related heteropolymers
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 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...
Nylon 6 and related homopolymers
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 a ring-opening polymerization. The peptide bond within the caprolactam is broken with the exposed active groupson 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...
Nylon 1,6
Nylons can also be synthesized from dinitriles using acid catalysis. For example, this method is applicable for preparation of nylon 1,6 from adiponitrile, formaldehyde and water. Additionally, nylons can be synthesized from diolsand dinitriles using this method as well.
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 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 ny...
Above their melting temperatures, Tm, thermoplastics like nylon are amorphous solids or viscous fluids in which the chains approximate random coils. Below Tm, amorphous regions alternate with regions which are lamellar crystals. The amorphous regions contribute elasticity, and the crystalline regions contribute strength and rigidity. The planar ami...
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.Its use increased dramatically during World War II, when the need for fabrics increased dramatically.
Kadolph, Sara J. (2007). Textiles. Pearson Prentice Hall. ISBN 978-0-13-118769-6.Kohan, Melvin (1995). Nylon Plastics Handbook. Munich: Carl Hanser Verlag. ISBN 1569901899.Making Nylon, Bob Burk, CHEM 1000, Carleton University, Ottawa, Canada on YouTubeJoseph X. Labovsky Collection of Nylon Photographs and Ephemera Science History InstituteDigital Collections. (High-resolution scans of nylon-related photographs and ephemera collected by Joseph X....- 1.15 g/cm 3
- 463-624 K190-350 ° C374-663 ° F
- 10 −12 S /m
- 0.25 W / (m· K)
Apr 11, 2024 · Polyamide 6-6 (PA6-6) or Nylon 6-6 is one of the most popular engineering thermoplastics. It is majorly used as a replacement for metal in various applications. Nylon 66 is synthesized by polycondensation of hexamethylenediamine and adipic acid. These two monomers contain 6 carbon atoms each.
Polyamides, in a broad sense, comprise proteins and peptides, which are naturally occurring polymers that are made up of amino acid repeating units. Polyamides, also known as aramids, are divided into three categories: aliphatic, semiaromatic, and aromatic polyamides (Fig. 23.2). The most significant family of engineering thermoplastics is ...
