Nylon surfaces

Interfacial Energy of Adhesion. When the polyelectrolyte-grafted nylon surface, in equilibrium with 50% relative humidity, is brought into contact with water or a salt solution, various interactions will occur together they comprise the reversible work of adhesion or free energy of adhesion at the interface of these two phases. This free energy of adhesion should be composed of the following contributions ... 

Thus, in general for any counterion species the free energy of adhesion will probably always be higher and the contact angle lower when more counterions are able to escape the local fields of the individual charges on the polyelectrolyte. Figure 8 depicts schematically this behavior for the different counterions. Therefore, for grafted polyquaternary cations on a nylon surface, the counterions F", CT, and I03 are... 

Figure 26.1 Effect of contact time on the water droplet volume of many different size droplets on Teflon and nylon surfaces.

Some nine years ago, Ellison and Zisman [4] reported their study of the wettability of 6-6 nylon (polyhexamethylene adipamide) and compared their results to those previously obtained on polyethylene [7]. They found that the nylon was more easily wet than the polyethylene, especially by hydrogen-bonding liquids, and attributed these findings to the presence of amide groups in the nylon surface. 

It was reasoned that the indicated alternation of polymer wettabilities had to result from differences in density, orientation, and/or bonding of the amide groups in the nylon surfaces. Consequently,an attempt was made to relate the observed wettabilities to polymer morphology. 

Uses Dyeing textiles, sheepskins, furs colorant for polymethyl methacrylate and nylon surface dyeing of cellulose acetate Regulatory SARA 313 reportable Manuf./Distrib. Aldrich http //www.sigma-aldrich.com, ICN Biomed. Research Prods. http //www.icnbiomed.com Disperse yellow 54... 

As a general rule, nylon surfaces demand great care in preparation for bonding. 

Figure 7-71. The bonding of two thermoformed parts from coextruded sheets here resulted in a fuel tank. The tank s inside has a nylon surface to resist gasoline the outside uses PP to provide a combination of low cost and the required support strength.

Extremely close tolerances such as might be necessary for a seal or a bearing may not be within the capabilities of the STX molding process. Machining is not recommended because it would break the nylon surface and expose the glass fibers that then act as wicks for fluid. An aluminum insert that has been finish machined is used as a substitute. Since the ratios of the moduli are quite large (about 20 1 for steel and 10 1 for aluminum), there will be no deformation of the metal insert and only the plastic will be highly stressed. It is most important that... 

Reaction with hydroxysuccinimide ester-activated nylon surfaces Entrapment in cellulose fibres with optional glutaraldehyde-fixing Entrapment in a cross-linked poly-(2-hydroxyethyI methacrylate) gel Entrapment in density-adjusted cellulose acetate or adsorption and cross-linking onto density-adjusted nylon Entrapment in polyf V-vinylpyrrolidone) Entrapment within the lattice of polyacrylamide gel... 

Reaction with hydroxysuccinimide ester-activated nylon surfaces Adsorption onto DEAE-cellulose... 

A polyamide (nylon) surface resists the dense subvisual growth. Although some influence of moisture alone is noted, isolated patches of visible mold growth have no effect. 

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