Poly caprolactam

Table 9.3 lists the intrinsic viscosity for a number of poly(caprolactam) samples of different molecular weight. The M values listed are number average figures based on both end group analysis and osmotic pressure experiments. Tlie values of [r ] were measured in w-cresol at 25°C. In the following example we consider the evaluation of the Mark-Houwink coefficients from these data. 

Table 9.3 Intrinsic Viscosity as a Function of Molecular Weight for Samples of Poly(caprolactam) ...

Evaluate the Mark-Houwink coefficients for poly (caprolactam) in w-cresol at 25°C from the data in Table 9.3. 

Mercapto groups in poly(caprolactam) fibers having disulfide and alkalene sulfide cross-links have been determined by swelling the sample with methanol and titrating the suspended strips with an alcoholic silver nitrate solution [1,33]. 

The conditions used for a radical reaction could require a modification of the mechanochemical polycondensation. Such a polycondensation of poly ( -caprolactam) was carried out using sebacic acid dichloride as a condensing agent. For the mechanochemical polycondensation of all the other polymers, aliphatic and aromatic diamines were used. In all cases, the reaction was followed by determining chemically linked nitrogen, which decreased in the first case (owing to the fixation of acid dichloride) and increased in the remaining ones because of the reactions with diamines. 

A number of polyamide copolymers are known to have practical uses. The copolymers include those with different amides such as poly(caprolactam-co-laurolactam), poly(2,2,4-trimethyl-1,6-hexandiamine-co-2,4,4-trimethyl-1,6-hexandiamnie-co-1,4-benzendicarboxylic acid), poly(s-caprolactam-co-hexamethylene diamine-co-terephthalic acid), poly(hexamethylenediamine-co-terephthalic acid-co-isophthalic acid), etc. The addition of longer alkyl chains in an aromatic polymeric amide may improve some mechanical properties, but thermal resilience is in general reduced. For example, poly(hexamethylenediamine-co-m-xylylenediamine-co-isophthalic acid-co-terephthalic acid) starts decomposing at about 310° C, significantly lower than Nomex , for example. The same decrease in the decomposition temperature is seen for other mixed copolymers such as nylon 12 copolymers that include cycloaliphatic and aromatic segments. 

PVC or C-PVC with poly(caprolactam-co-caprolactone) Samples by co-precipitation from p-xylene, THE or DMSO. DSC at 10°C. Tg onset and inflection point. van Ekenstein et al., 1997... 

Details A crystalline solid, the monomer for poly-caprolactam (Nylon 6). 

Equations (6.32) to (6.34) have been successful in describing the PVT dependencies of PE [Simha and Jain, 1978 Jain and Simha, 1979a, b] and more recently of the poly( -caprolactam) (PA-6) [Utracki, 2009a,b,c,e]. In the latter case, owing to great variability of the crystalline content with T, P, and composition, the Pastine idea of additivity of the crystalline and noncrystalline domains has been applied. 

Utracki, L. A., Simha, R., and Garcia-Rejon A., Pressure-volume-temperature dependence of poly- -caprolactam/clay nanocomposites. Macromolecules, 36(6), pp. 2114-2121 (2003). 

STRUCTURE These aromatic nylons consist of aliphatic and aromatic building blocks incorporating the repeat units of nylon 6 — poly(caprolactam) — and nylon 6T — poly(hexamethylene terephthalamide). Because of this composition, Ultramid T resins are often designated as nylon 6/6T materials. The basic structure is nylon 6/6T, with a majority component of nylon 6. 

OTHER POLYMERS SHOWING THIS SPECIAL PROPERTY Poly( -caprolactam) (Nylon 6). (See also the entry on Nylon 6 in this handbook.)... 

Figure 5-10. Pleated sheet structures of polyamide 6 [poly(caprolactam)] and polyamide 6,6 [poly(hexamethylene adipamide)].

X—NHCOCHj ) (X = poly caprolactam chain) Mechanical degradation of polycaprolactam/ Solid polymer EPR/ 77 2H(a) 1.9 67Zakl... 

Commercial products are frequently referred to as nylons without further differentiation, and are distinguished from each other by numbers or letters. The numbers indicate the number of carbon atoms per aliphatic monomeric unit. Thus, nylon 6 or polyamide 6 is poly( -caprolactam). In the authentic nylon series, there are two numbers the first number refers to the number of carbon atoms in the diamine component and the second number to the number of carbon atoms in the dicarboxylic acid component. Consequently, nylon 6,6 or nylon 66 is poly(hexamethylene adipamide). Letters are often used to designate cyclic units, i.e., T for the terephthalic acid residue. 

Nylon 6 Poly(caprolactam). Degradation slow bioerosion. 

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