Names | |
---|---|
IUPAC name Poly[imino(1,6-dioxohexamethylene) iminohexamethylene] | |
Systematic IUPAC name Poly(azanediyladipoylazanediylhexane-1,6-diyl) | |
Other names Poly(hexamethylene adipamide),Poly(N,N'-hexamethyleneadipinediamide), Maranyl, Ultramid, Zytel, Akromid, Durethan, Frianyl, Vydyne | |
Identifiers | |
ChemSpider |
|
ECHA InfoCard | 100.130.739 |
PubChem CID | |
CompTox Dashboard (EPA) | |
Properties | |
(C12H22N2O2)n | |
Density | 1.140 g/ml (Zytel) |
Melting point | 264 °C (507 °F) |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
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] Aside from its superior physical characteristics, nylon 66 is attractive because its precursors are inexpensive.
Nylon 66 is synthesized by polycondensation of hexamethylenediamine and adipic acid. Equivalent amounts of hexamethylenediamine and adipic acid are combined in water. In the original implementation, the resulting ammonium/carboxylate salt was isolated and then heated either in batches or continuously to induce polycondensation. [2]
Removing water drives the reaction toward polymerization through the formation of amide bonds from the acid and amine functions. Alternatively, the polymerization is conducted on a concentrated aqueous mixture formed of hexamethylenediamine and adipic acid. [3]
It can either be extruded and granulated at this point or directly spun into fibers by extrusion through a spinneret (a small metal plate with fine holes) and cooling to form filaments.
In 2011 worldwide production was two million tons. At that time, fibers consumed just over half of production and engineering resins the rest. It is not used in film applications as it cannot be biaxially oriented. [4] Fiber markets represented 55% of the 2010 demand with engineering thermoplastics being the remainder. [5]
Nylon 66 is frequently used when high mechanical strength, rigidity, good stability under heat and/or chemical resistance are required. [6] It is used in fibers for textiles and carpets and molded parts. For textiles, fibers are sold under various brands, for example Nilit brands or the Cordura brand for luggage, but it is also used in airbags, apparel, and for carpet fibres under the Ultron brand. Nylon 66 lends itself well to make 3D structural objects, mostly by injection molding. It has broad use in automotive applications; these include "under the hood" parts such as radiator end tanks, rocker covers, air intake manifolds, and oil pans, [7] as well as numerous other structural parts such as hinges, [8] and ball bearing cages. Other applications include electro-insulating elements, pipes, profiles, various machine parts, zip ties, conveyor belts, hoses, polymer-framed weapons, and the outer layer of turnout blankets. [9] Nylon 66 is also a popular guitar nut material. [10]
Nylon 66, especially glass fiber reinforced grades, can be effectively fire retardant with halogen-free products. Phosphorus-based flame retardant systems are used in these fire-safe polymers and are based on aluminium diethyl phosphinate and synergists. They are designed to meet UL 94 flammability tests as well as Glow Wire Ignition Tests (GWIT), Glow Wire Flammability Test (GWFI) and Comparative Tracking Index (CTI). Its main applications are in the electrical and electronics (E&E) industry.
In polymer chemistry, condensation polymers are any kind of polymers whose process of polymerization involves a condensation reaction. Condensation polymers are formed by polycondensation, when the polymer is formed by condensation reactions between species of all degrees of polymerization, or by condensative chain polymerization, when the polymer is formed by sequential addition of monomers to an active site in a chain reaction. The main alternative forms of polymerization are chain polymerization and polyaddition, both of which give addition polymers.
Nylon is a generic designation for a family of synthetic polymers composed of polyamides. Nylon is a silk-like thermoplastic, generally made from petroleum, that can be melt-processed into fibers, films, or shapes. Nylon polymers can be mixed with a wide variety of additives to achieve many property variations. Nylon polymers have found significant commercial applications in fabric and fibers, in shapes, and in films.
Aramid fibers, short for aromatic polyamide, are a class of heat-resistant and strong synthetic fibers. They are used in aerospace and military applications, for ballistic-rated body armor fabric and ballistic composites, in marine cordage, marine hull reinforcement, as an asbestos substitute, and in various lightweight consumer items ranging from phone cases to tennis rackets.
Adipic acid or hexanedioic acid is the organic compound with the formula (CH2)4(COOH)2. From an industrial perspective, it is the most important dicarboxylic acid: about 2.5 billion kilograms of this white crystalline powder are produced annually, mainly as a precursor for the production of nylon. Adipic acid otherwise rarely occurs in nature, but it is known as manufactured E number food additive E355. Salts and esters of adipic acid are known as adipates.
Adipoyl chloride (or adipoyl dichloride) is the organic compound with the formula (CH2CH2C(O)Cl)2. It is a colorless liquid. It reacts with water to give adipic acid.
Step-growth polymerization refers to a type of polymerization mechanism in which bi-functional or multifunctional monomers react to form first dimers, then trimers, longer oligomers and eventually long chain polymers. Many naturally occurring and some synthetic polymers are produced by step-growth polymerization, e.g. polyesters, polyamides, polyurethanes, etc. Due to the nature of the polymerization mechanism, a high extent of reaction is required to achieve high molecular weight. The easiest way to visualize the mechanism of a step-growth polymerization is a group of people reaching out to hold their hands to form a human chain—each person has two hands. There also is the possibility to have more than two reactive sites on a monomer: In this case branched polymers production take place.
Polyphthalamide is a subset of thermoplastic synthetic resins in the polyamide (nylon) family defined as when 55% or more moles of the carboxylic acid portion of the repeating unit in the polymer chain is composed of a combination of terephthalic (TPA) and isophthalic (IPA) acids. The substitution of aliphatic diacids by aromatic diacids in the polymer backbone increases the melting point, glass transition temperature, chemical resistance and stiffness.
Adiponitrile is an organic compound with the chemical formula (CH2)4(CN)2. This viscous, colourless dinitrile is an important precursor to the polymer nylon 66. In 2005, about one million tonnes of adiponitrile were produced.
In step-growth polymerization, the Carothers equation gives the degree of polymerization, Xn, for a given fractional monomer conversion, p.
Polyester is a category of polymers that contain the ester functional group in every repeat unit of their main chain. As a specific material, it most commonly refers to a type called polyethylene terephthalate (PET). Polyesters include naturally occurring chemicals, such as in plants and insects, as well as synthetics such as polybutyrate. Natural polyesters and a few synthetic ones are biodegradable, but most synthetic polyesters are not. Synthetic polyesters are used extensively in clothing.
Sebacoyl chloride (or sebacoyl dichloride) is a di-acyl chloride, with formula (CH2)8(COCl)2. A colorless oily liquid with a pungent odor, it is soluble in hydrocarbons and ethers. Sebacoyl chloride is corrosive; like all acyl chlorides, it hydrolyzes, evolving hydrogen chloride. It is less susceptible to hydrolysis though than shorter chain aliphatic acyl chlorides.
Hexamethylenediamine is the organic compound with the formula H2N(CH2)6NH2. The molecule is a diamine, consisting of a hexamethylene hydrocarbon chain terminated with amine functional groups. The colorless solid (yellowish for some commercial samples) has a strong amine odor. About 1 billion kilograms are produced annually.
Nylon 11 or Polyamide 11 is a polyamide, bioplastic and a member of the nylon family of polymers produced by the polymerization of 11-aminoundecanoic acid. It is produced from castor beans by Arkema under the trade name Rilsan.
Laurolactam is an organic compound from the group of macrocyclic lactams. Laurolactam is mainly used as a monomer in engineering plastics, such as nylon-12 and copolyamides.
RadiciGroup is an Italian corporation with a network of production and sales sites located in Europe, North America, South America and Asia. RadiciGroup is one of the world’s leading producers of a wide range of chemical intermediates, polyamide polymers, engineering plastics, synthetic fibres and nonwovens.
Aluminium diethyl phosphinate is a chemical compound with formula Al(C
4H
10O
2P)3. It decomposes above 300 °C.
Nylon 12 is a nylon polymer with the formula [(CH2)11C(O)NH]n. It is made from ω-aminolauric acid or laurolactam monomers that each have 12 carbons, hence the name ‘Nylon 12’. It is one of several nylon polymers.
Nylon 46 is a high heat resistant polyamide or nylon. DSM is the only commercial supplier of this resin, which markets under the trade name Stanyl. Nylon 46 is an aliphatic polyamide formed by the polycondensation of two monomers, one containing 4 carbon atoms, 1,4-diaminobutane (putrescine), and the other 6 carbon atoms, adipic acid, which give nylon 46 its name. It has a higher melting point than nylon 6 or nylon 66 and mainly used in applications which must withstand high temperatures.
Nylon 1,6 is a type of polyamide or nylon. Unlike most other nylons, nylon 1,6 is not a condensation polymer, but instead is formed by an acid-catalyzed synthesis from adiponitrile, formaldehyde, and water. The material was produced and studied by researchers at DuPont in the 1950s. Synthesis can be performed at room temperature in open beakers.
Gérard Berchet was a French-American chemist who played a pivotal role in the invention of both nylon and neoprene. Berchet worked under the direction of Wallace Carothers at DuPont Experimental Station and first synthesized nylon 6 on February 28, 1935, from equal parts hexamethylenediamine and adipic acid. Berchet was the first to synthesize neoprene. However, Arthur Collins is credited with its discovery on April 17, 1930, after he accidentally reacted hydrochloric acid with vinylacetylene. Berchet's leaving of his sample unexamined on a laboratory bench until after Collin's discovery prevented him from being credited with its discovery.