Hexamethylene diamine carbonate

Nylon A class of synthetic fibres and plastics, polyamides. Manufactured by condensation polymerization of ct, oj-aminomonocarboxylic acids or of aliphatic diamines with aliphatic dicarboxylic acids. Also rormed specifically, e.g. from caprolactam. The different Nylons are identified by reference to the carbon numbers of the diacid and diamine (e.g. Nylon 66 is from hexamethylene diamine and adipic acid). Thermoplastic materials with high m.p., insolubility, toughness, impact resistance, low friction. Used in monofilaments, textiles, cables, insulation and in packing materials. U.S. production 1983 11 megatonnes. 

Hexamethylene diamine (116 g), sodium carbonate (466 g), and water (800 ml) were heated to 60°C, and dimethyl sulfate (830 g) added with stirring over 1% hours keeping the temperature below 90°C. The reaction mixture was then stirred at 90°C for 2 hours, then cooled to 20°C, acetone (1,200 ml) added and the whole cooled to 0°C. 

Numbers that follow the word nylon denote the number of carbons present within a repeating unit and whether one or two monomers are being used in polymer formation. For nylons using a single monomer such as nylon 6 or nylon 12, the numbers 6 and 12 denote the number of carbons in caprolactam and laurolactam, respectively. For nylons using two monomers such as nylon 610, the first number, 6, indicates the number of carbons in the hexamethylene diamine and the other number, 10, is for the second monomer sebacic acid. 

Polymers are further defined based on the number of carbon atoms they contain. Thus, the PA based on 1,6-hexamethylene diamine and sebacic acid is named PA-6,10 and the polymer based on caprolactam, PA-6. Terephthalic and isophthalic acid units are coded T and I. Thus, PA-6,T represents the PA from hexamethylene diamine and terephthalic acid. 

On February 28, 1935, Carothers project succeeded beyond anyone s wildest dreams. The cheerful, lively Frenchman Berchet produced a superpolymer made from chemicals derived from cheap benzene, a by-product of coal later they would be made from petroleum. A filament teased from Berchet s polymer was, despite its lowly origins, pearly and lustrous. And when it was tested, it proved to be spinnable. Its code name was 6-6 because both its reactants—hexamethylene diamine and adipic acid—had six carbon atoms. Technically, the filament was polyhexamethylene adipamide, a long-chain polymer similar in structure to proteins. It became world-famous as nylon. 

The product obtained is known as nylon 6, 6 as there are six carbon atoms in diamine and 6 carbon atoms in diacid. Nylon 6, 10 is obtained by a similar method from hexamethylene diamine and sebacic... 

Example 2-11 The monomers for nylon are either the amino acid H2N-(CH2)sCOOH, which forms the polymer called Nylon 6 (six carbon atoms in the backbone) or two monomers adipic acid HOOC-(CH2)4COOH and hexamethylene diamine H2N-(CH2)6NH2, which form the polymer called Nylon 66 (six carbon atoms in the backbone of each of the monomers). It is possible to make the 6-carbon atom monomers very easily with high purity, but the production of nylons with five, seven, or other carbons would be very difficult. Why ... 

We form an amide linkage between the adipoyl chloride and the amine with the elimination of HC1. The polymer is called nylon 6-6 because there are six carbon atoms in the acyl chloride and six carbon atoms in the diamine. Other nylons, such as nylon 10-6, are made of sebacoyl chloride (a 10-carbon atom containing acyl chloride) and hexamethylene diamine (a six carbon atom containing diamine). We use an acyl chloride rather than a carboxylic acid to form the amide bond because the former is more reactive. NaOH is added to the polymerization reaction in order to neutralize the HC1 that is released every time an amide bond is formed. 

Nylon is the common name for polyamides. Polyamides are generally made from reactions of diacids with diamines. The most common polyamide is called nylon 6,6 because it is made by reaction of a six-carbon diacid (adipic acid) with a six-carbon diamine. The six-carbon diamine, systematically named hexane-1,6-diamine, is commonly called hexamethylene diamine. When adipic acid is mixed with hexamethylene diamine, a proton-transfer reaction gives a white solid called nylon salt. When nylon salt is heated to 250 °C, water is driven off as a gas, and molten nylon results. Molten nylon is cast into a solid shape or extruded through a spinneret to produce a fiber. 

The polycondensation of furfural with w-phenylene diamine, / phenylene diamine, or hexamethylene diamine in dimethylformamide at 80-85 °C using zinc chloride or carbon tetrachloride as a catalyst affords anion-exchange resins having.high... 

Suppose we wish to prepare a nylon with an M of 16,000 using adipic acid (H02C(CH2)4C02H) and hexamethylene diamine (H2N(CH2)gNH2), which represents an A-A, B-B type of polycondensation. The common, or trade name of the product, poly(hexamethylene adipamide), H0[0C(CH2)4 CONH(CH2)gNH] H, is nylon 6,6, or nylon 66. The first 6 refers to the number of carbon atoms between amide nitrogens for the amine component, and the second 6 refers to the number of carbon atoms separating nitrogens for the acid component. What monomer feed ratio would be required to achieve this M ... 

When this theory had received recognition, an intense search for appropriate monomers was set in motion. At that time the most suitable known reaction was condensation between adipic acid, (COOH.(CH ),.COOH), and hexamethylene diamine, (NH2.(CH2)i .NH ), to form what was knowm as a superpolyamide subsequently placed on the market as nylon 1 he significance of 66 is that the monomers each have six carbon atoms.. vlon is a general name for all superpolyamide fibres and 66 serves as a distinc-... 

The hexamethylene di-isocyanate is prepared by dissolving hexamethylene-diamine in dichlorobenzene, converting into hexamethylene diammonium carbonate by passing COj into the solution and then treating with phosgene ... 

Octadecyl Amine Stearic Acid Carbon Black N760 Vanfre UN Hexamethylene Diamine Dl-O-tolyIguanidine... 

FIGURE 4.1 Influence of modifier HUM-01 (trimethyl-hexamethylene-diamine + propylene carbonate) on gel time of epoxy composition based on D.E.R. 331. (Reprinted from O. Figovsky, O. Birukov, L. Shapovalov, and A. Leykin, Hydroxyurethane Modifier as Effective Additive for Epoxy Matrix, Scientific Israel Technological Advantages 13, no. 4 (2011) 122-128. With permission.)... 

Nylon 6 6 = hexamerhylene diamine (6) + adipic acid (6) Nylon 6 10 = hexamethylene diamine (6) + sebacic acid (10) (number of carbon atoms in brackets)... 

Cyclohexanone, a six-membered carbon ring with a ketone as functional group, is almost exclusively applied as a precursor for the production of aliphatic polyamides. Pure cyclohexanone is mainly converted, via cyclohexanone oxime and caprolactam, to nylon-6 (also called polycaprolactam) [1]. Mixtures of cyclohexanone and cyclohexanol, often called K4 oil, are converted via oxidation into adipic acid that reacts with hexamethylene diamine (HMDA) to nylon-6,6 (poly-hexamethylene adipamide). Other applications of these products can be found in the field of polyurethane and polyester production. 

The nylons are named by the number of carbon atoms in the repeat units. The materials formed by polymerizations of lactams therefore carry only one number in their names like, for instance, nylon 6 that is formed from caprolactam. By the same method of nomenclature, a nylon prepared by condensing a diamine with a dicarboxylic acid like, for example, hexamethylene diamine with adipic acid, is called nylon 6,6. It is customary for the first number to represent the number of carbons in the diamine and the second number to represent the number of carbons in the diacid. 

Polyamides of this type are called nylon ( , m 2), where n is the number of carbons in the diamine monomer and m - - 2 is the number of carbons in the diacid. Nylon 6,6, the most commercially important aliphatic polyamide with this structure, is produced from hexamethylene diamine (HMD) ( = 6) and adipic acid (m- -2 = 6). Nylon 4,6, nylon 6,10 and nylon 6,12 are also produced commercially [1]. 

E. coli and S. aureus Some quinuclidinium compounds were quite active in vitro with the most active XVIII having MIC values of 0.4 ug/ml for S. aureus and B. subtilis. A group of 68 N,N-dimethyl-N-alkyl-2-aryloxyethyl ammonium bromides were prepared and screened vs 8 common infectious organisms, and the best had alkyl groups of from 8-12 carbon atoms, with MIC values as low as 0.5 yg/ml. Bis-quaternary salts of ethylene and hexamethylene diamine of type XIX were active in vitro . The most active had R=CioH2i and the chloride had greater activity than the corresponding iodide. Another paper dealt with the structure-activity relationships of compounds of type XIX . Various physical properties such as pH, wettability, viscosity, surface tension, etc. were related to activity. 

In another approach, soybean oil fatty acid derivatives are carbonated in supercritical carbon dioxide which is then converted to polyurethane by reaction with primary amines such as ethylenediamine, hexamethylene-diamine and tris(2-aminoethyl)amine. This technique avoids the use of isocyanates (usually phosgene, a deadly poisonous gas which is used to obtain isocyanate) and the resultant polyurethane networks exhibited Tg values of approximately 34°C, 18°C and 43°C, respectively for the above amines. ... 

When one unit A is followed by one unit B, followed by one unit A, etc., the copolymer is alternate and named poly( A-alt-B), but it can also be named poly (A-B). Polyamide 6-6 (Nylon 6-6) is an example of a completely alternate copolymer the monomer unit resulting from reaction of hexamethylene diamine is followed by the monomer unit resulting from the dicarboxylic acid containing six carbon atoms. 

Interfadal polymerization n. A polymerization reaction that occurs at or near the interfacial surfaces of two immiscible solutions. A simple example is the often-performed demonstration of making nylon thread from a beaker containing a lower layer of a solution of sebacyl chloride in carbon tetrachloride and an upper layer of hexamethylene diamine solution in water. A pair of tweezers is gently lowered through the upper layer, closed on the interfadal layer of polymer, and then drawn upward to pull with it a continuous strand of nylon 6/10. 

Even though water has a low solubility in carbon dioxide, it has been shown that it can also be effectively removed with supercritical carbon dioxide in formation of nylon 66 (a polyamide) [34]. In this polyamide formation, because of the reactivity of carbon dioxide with amines, instead of using hexamethylene diamine, reaction was carried out with a nylon salt. Carbon dioxide was shown to lower the melting point of the nylon salt and permit polymerization to proceed at lower temperatures. At temperatures around 270 and over a reaction time of about 3 hr at 3000 psi polyamides of high molecular weight (Mn = 25,000) have been produced. 

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