Plasma polymerization coating

Overcoats are an integral part of thin-film disk structures. Their primary role is to provide wear protection. The most common overlayers, such as Rh, plasma-polymerized coatings, SiOz, and carbon, are all chemically stable if they were fully to cover the disk surface, they would provide good corrosion resistance. The thinness of the overcoats and the roughness of the surface preclude perfect coverage and open up the path for localized corrosion at the sites where the magnetic layer is exposed to the environment. 

Bouaidat S, Berendsen C, Thomsen P et al (2004) Micro patterning of cell and protein nonadhesive plasma polymerized coatings for biochip applications. Lab on a Chip 4(6) 632-637... 

SAIE corrosion protection emphasizes the fact that the corrosion protection of a metal depends on the overall corrosion protective behavior of an entire system. If a plasma polymerization coating is changed, all factors must be optimized to yield the best result that can be attributed to the change. The essence of interface engineering lies in the tailoring of surfaces to facilitate the equilibration of surface states of different materials. 

Figure 26.8 The effects of plasma polymerization coatings on the wettability of conventional polymers given by the cosine of the static advancing contact angle, 0s each value of the static contact angle was taken for the largest droplet size attained during the advancing process whereby the droplet size dependence is small, dotted lines indicate the mean cos 0s of the TMS and (TMS + O2) treated polymers.

Similar to static contact angles from the sessile droplet method, Wilhelmy dynamic contact angles are an excellent indication of the change in surface characteristics due to surface modification techniques such as plasma polymerization coating. The cosine of dynamic advancing contact angles from the first immersion, cos 0D,a,i of untreated, TMS-treated, and (TMS-I-02)-treated conventional... 

The force loop for untreated samples are shown in Figure 26.14. The force loops for TMS plasma-treated and (TMS O2) plasma-treated surfaces are shown in Figure 26.15. Any sign of deviation from the parallelogram force loop is an indication of surface dynamic instability. Plasma polymerization coating of (TMS O2) seems to cause some degree of surface dynamical instability depending on the nature of substrate polymer, e.g., PTFE, UHMWPE, HDPE, and PMMA. 

Figure 29.1 A simplified schematic view of a plasma polymerization coating applied on a phase-separated silicone-hydrogel polymer.

When a nanofilm of plasma polymerization coating is applied on a polymer surface, the surface dynamic changes were still observed in spite of tight network structure of plasma polymers, and the rates of surface dynamic change differ depending on the nature of the polymers. The higher level of surface dynamic changes was often observed with polymers coated with plasma polymer of perfluorocarbons because... 

Contact angles of water and of XPS FIs peaks for the subsequently treated samples showed the effect of the operational parameters of plasma polymerization coating of methane on the perturbability of the final surface with CF4 plasma treatment. The conditions of the plasma polymerization coating are manifested... 

Contact angles of water on various samples after they are immersed in water for various periods of time are shown in Table 29.4. The decay of hydrophobicity due to water immersion is less for samples prepared with plasma polymerization coating of... 

Figure 29.9 ESCA FIs peak intensities for dry and water-immersed CF4 plasma treated plasma polymerization coating of CH4 (on PET) as functions of WjFM values of CH4 plasma polymerization (thickness = 60 nm).

Figure 29.11 Changes in ESCA signals of PET films due to the plasma polymerization coating of CH4, CF4 plasma labeling, and subsequent water immersion for 120 min W/FM for CH4 plasma polymerization 5.0GJ/kg, thickness 120 nm.

Figure 29.13 Effect of W/FM of plasma polymerization coating of CH4 on the decay rate constant, k, for the coating deposited on nylon 6 and PET film.

Figure 34.3 Modes of plasma polymerization coating, (a) on nonporous membrane, and (b) on porous membrane.

Figure 34.20 The influence of different substrate hollow fibers on (a) air enrichment factor, and (b) air flux of composite membranes prepared by deposition of plasma polymerization coating of 1,1,3,3-tetramethyldisiloxane.

Figure 34.22 Schematic cross-sectional view of plasma polymerization coated large pore membrane.

Figure 35.4 Effect of coating thickness on the frictional coefficient of coating of CH4 plasma polymerization coating.

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