Plasma coating properties

Surface modification of silica, another filler used in the rubber industry, has been reported by Nah et al. [36, 37]. The silica surface was modified by plasma polymerization of acetylene. The modified silica was mixed with SBR to study its performance. They observed an increase in reinforcement with the plasma-modified silica and hence better mechanical properties. They also observed an improvement in the dispersion properties for the plasma-coated silica. The authors explained the observed improvement in properties by a mild crosslinking between plasma-polymerized acetylene and the butadiene part of the SBR matrix. 

Effect of Plasma-Coated Silica on SBR Compound Properties... 

Application of a plasma coating onto carbon black is very difficult compared to silica. It was only practically feasible for fullerene soot (left over from the fullerene production), which contains a large amount of reactive groups on its surface. Polyacetylene-plasma-treated fullerene soot provides an improved dispersion in SBR and in a SBR/EPDM blend compared to untreated fullerene black. However, the effect on the stress-strain properties is rather limited and the coating has only a slight effect on the final properties. 

The expansive internal stress in a plasma polymer is a characteristic property that should be considered in general plasma polymers and is not found in most conventional polymers. It is important to recognize that the internal stress in a plasma polymer layer exists in as-deposited plasma polymer layer, i.e., the internal stress does not develop when the coated film is exposed to ambient conditions. Because of the vast differences in many characteristics (e.g., modulus and thermal expansion coefficient of two layers of materials), the coated composite materials behave like a bimetal. Of course, the extent of this behavior is largely dependent on the nature of the substrate, particularly its thickness and shape, and also on the thickness of the plasma polymer layer. This aspect may be a crucial factor in some applications of plasma polymers. It is anticipated that the same plasma coating applied on the concave surface has the lower threshold thickness than that applied on a convex surface, and its extent depends on the radius of curvature. 

Thus, without SAIE, Parylene C film, which has excellent barrier and physical properties, cannot be utilized in corrosion protection of a metal. Conversely, SAIE is the key to yield an excellent corrosion protection systems. It is also important to recognize how a nanofilm of hydrophobic amorphous network of plasma coating can prevent the initiation of the salt intrusion process. 

In order to explore the possibility of efficiently operating plasma deposition in an industrial IVD reactor, DC cathodic polymerization of TMS in a closed system mode under conditions similar to the IVD operation was investigated. The corrosion protection properties of the plasma coatings obtained under such operation were also studied on IVD Al-coated A1 alloys. 

Besides the advantageous features described earlier, DC cathodic plasma polymerization of TMS mixed with argon also provides an opportunity to combine the two processes of TMS deposition and second plasma treatment into a single step. TMS plasma coating thus produced also maintains excellent corrosion protection properties on the aluminum alloy substrates. 

The superior corrosion performance and strong adhesion of the plasma coating system can be attributed to the coating properties and, more importantly, to the nature of interfacial chemistry. Two techniques were applied to study the surface and interfacial chemistry of the plasma coating system (1) in situ plasma deposition and XPS analysis and (2) in-depth profiling of sputtered neutral mass spectroscopy (SNMS). 

Using CaTiZr3(P04)6 as feedstock material, parametric studies were carried out (Heimann, 2006b) to evaluate the influence of seven intrinsic and extrinsic plasma spray parameters varied at two levels (Table 6.8) on six coating properties (Table 6.9) using a Plackett-Burman (Box, Hunter and Hunter, 1978) SDEs matrix with number of variables p = 11 and number of runs N = 12. As only 7 out of 11 matrix variables (factors) were defined (Table 6.8), the remaining four empty factors can be used to estimate the mean standard deviation of the factor effects sFE and hence the minimum factor significance (Min). 

Tsui, Y.C., Doyle, C., and Clyne, T.W. (1998b) Plasma sprayed hydroxyapatite coatings on titanium substrates. Part 2 optimisation of coating properties. Biomaterials, 19, 2031-2043. 

The performance metrics used to judge the quality of a given antireflection coating include optical parameters (n and k), plasma etch rate, coating properties (whether highly planarizing or somewhat conformal), reflectivity, thickness, and compatibility with the given resist to which it is paired. 

Jaroszewski M., Pospieszna J., Ziaja J. (2010). Dielectric properties of polypropylene fabrics with carbon plasma coatings for applications in the technique of... 

Plasma treatment refers to the surface modification processes of materials using nonequUibrium gas plasmas. Nonequilibrium plasmas with a low degree of ionization, so-called cold plasmas or low-temperature plasmas, are mainly composed of electrons, ions, free radicals, and electronically excited atomic and molecular species. These highly reactive plasma species interact nonthermally with material surfaces and can react with and bond to various substrate surfaces or combine together to form an ultrathin layer of plasma coating and consequently alter the surface chemistry and surface properties. The plasma-treated nanoparticles and/or nanotubes with desired surface functionalities can strongly interact with liquid molecules and thus better disperse into the base fluid to form stable suspension. 

Sherif and Shyu [163] used three different routes for particle synthesis (Section 4.3) all-alkoxides, salt/alkoxide and all-salts. Plasma sprayed coatings on steel coupons exhibited somewhat similar properties, though the best results were obtained with powders from the all-salts route. Table 6.1 presents a comparison of some of the coating properties with those obtained from a commercial powder prepared under the same set of conditions. 

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