Nylons structural formulas

When adipic acid (hexanedioic acid) and hexamethylenediamine (1,6-diamino-hexane) are mixed, a salt is obtained. On heating, this salt is converted into Nylon 66, a high-molecular-weight compound of formula (Ci2H2202N2)n. (a) Draw the structural formula for Nylon 66. To what class of compounds does it belong (b) Write an equation for the chemistry involved when a drop of hydrochloric acid makes a hole in a Nylon 66 stocking. 

Nylon 610 and two kinds of poly(propylene oxide) (PPO) segmented nylon 610 with different weight fraction of PPO were used in this study. The structural formulae of these polymers are ... 

Polyamides are also krrown as nylons. Polyamide polymers are available in several grades and are identified by the number of carbon atoms in the diamine and dibasic acid used to produce the particular grade. For example, nylon 6/6 is the reaction product of hexamethylenediamine and adipic acid, both of which are compoimds containing six carbon atoms. Some of the commonly commercially available nylons are 6, 6/6, 6/10,11, and 12. Their structural formulas are as follows ... 

Hydrogen bonding between polyamide chains plays an important role in determining the properties of a nylon such as nylon 6,6 (Table 12.5). Draw the structural formulas for two adjacent chains of nylon 6,6 and show where hydrogenbonding interactions could occur between them. 

Nylon 6,10 [Problem 16.3(d)] can be prepared by reacting a diamine and a diacid chloride. Draw the structural formula of each reactant. 

Using full structural formulas, draw a typical portion of a Nylon-6,6 molecule that is, expand a portion of the formula given in Equation 22.15. Show at least two hexanedioic acid units and two 1,6-hexanediamine units. 

Draw the structural formula (one repeating unit) for each of the following polymers (a) poly(4-methylpent-l-ene) (b) poly(chlorotri uoroethylene) (c) poly(vinyl ethyl ether) (d) poly(vinylidene chloride) (e) polyethyleneimine (f) poly(methyl-2-cyano-acrylate) (g) polychloroprene (h) poly(buty-leneterephthalate) (i) poly(l,2-propylene oxalate) (j) poly(dihydroxymethylcyclohexyl terephthalate) (k) poly-caprolactam (nylon-6) (1) polyformaldehyde (m) poly-oxymethylene (n) poly(propylene oxide) (o) poly (propylene glycol) (p) poly(p-phenylene sulfone) (q) poly(dimethyl siloxane) (r) poly (vinyl butyral) (s) poly (p-phenylene) (t) poly(p-xylylene) (u) polycaprolactone... 

Give structural formulas for the four-carbon diamine and the four-carbon diacid chloride that would react to form nylon. 

Nylon 6,10 is prepared by polymerization of a diamine and a diacid chloride. Draw a structural formula for each reactant and for the repeat unit in this polymer. 

A/f-copolymers have a unique situation among macromolecular compounds. They have an ordered structure of the type -[A-B-]n, which can be viewed as the structure of a homopolymer. The fact that a/f-copolymers can be formed from two starting monomers is not their unique property, and many homopolymers formed in step reactions have an -[A-B-]n formula. For example. Nylon 66, being formed from adipic acid and 1,6-hexandiamine, can be considered an a/f-copolymer and named poly(hexamethylene-diamine-a/f-adipic acid), or it can have the name poly(hexamethylene adipamide) or poly(iminohexa-methylene iminoadipoyl) and be viewed as a homopolymer with the structure -[NH-(CH2)6-NHC(0)-(CH2)4-C(O)-]n. Many other examples of the same type can be listed. 

Adipic acid, also known as hexanedioic acid, is an organic acid. It is a white, crystalline solid that is slightly soluble in water. In addition to being a corrosive, it is also flammable however, it is a relatively stable compound. Adipic acid is used in the manufacture of nylon and polyurethane foams. It is also a food additive and adhesive. The structure and molecular formula are shown in Figure 10.10 notice that the structure has two organic-acid functional groups attached. 

The general formula for the repeat unit of a polyamide described as nylon-n,m is -fNH(CH2) NH.CO(CH2) , 2CO. Particularly important examples are nylon-6,6, or poly(hexamethylene adipamide), and nylon-6,10. Related polyamides of slightly simpler structure have repeat units of the type -(-NH(CH2)5C0-)-, which is polycaprolactam, or nylon-6. 

Expressions such as —(—O—CH2—) — and (H2N—(CH2)6—NH2 HO2C— (0112)4—C02H)x depict actual structures, not molecular formulae. Although expressions such as (CH20)n and (C6Hi6N2 C6Hio04)a are used by CAS to represent the molecular formulae of poly(oxymethylene) and nylon-6,6 respectively, these expressions are, per se, neither structure-based nor source-based representations of these two polymers. There is a link, however, between the full structural representation and its molecular formula. The subscript n is used consistently for both an SRU and its molecular formula similarly, the subscript x is used consistently for both a homopolymer (copolymer) structure expressed in terms of monomer(s) and its corresponding molecular formula. 

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