Nanocomposite system applications coatings

These few examples show how the use of nanocomposite systems with hetero polysiloxane type of matrices leads to interesting properties for applications. Further developments using these basic systems are transparent controlled release coatings for anti-fogging systems [41], anti-corrosive systems for metal protection [42], and nanocomposite optical bulk materials [43],... 

Non-destructive surface-functionalization of carbon nanofibers can be achieved by using poly(3,4-ethylenedioxythiophene) (PEDOT) since PEDOT is an electron donor and carbon nanofiber is an electron acceptor [40]. PEDOT/carbon nanofiber nanocomposites can be prepared by chemical polymerization process. This includes an initial adsorption of EDOT monomers on the carbon nanofibers, which is followed by the polymerization process. The adsorption of monomers on the fiber surface occurs due to the electrostatic n-n interaction. PEDOT poly(styrenesulfonate) (PEDOT PSS)/carbon nanofiber bilayer system is used particularly for electrode applications [41]. Such bilayer systems can be easily prepared with dip-coating technique.The advantage of dip-coating is that only a small amount of polymer will be adsorbed on the carbon nanofiber surface and hence nanometer thick coating is achievable. The surface area of electroactive materials can be enhanced in such bilayer systems prepared with carbon nanofibers. 

This technique has found the following applications in addition to those discussed in Sections 10.1 (resin cure studies on phenol urethane compositions) [65], 12.2 (photopolymer studies [66-68]), and 13.3 (phase transitions in PE) [66], Chapter 15 (viscoelastic and rheological properties), and Section 16.4 (heat deflection temperatures) epoxy resin-amine system [67], cured acrylate-terminated unsaturated copolymers [68], PE and PP foam [69], ethylene-propylene-diene terpolymers [70], natural rubbers [71, 72], polyester-based clear coat resins [73], polyvinyl esters and unsaturated polyester resins [74], polyimide-clay nanocomposites [75], polyether sulfone-styrene-acrylonitrile, PS-polymethyl methacrylate (PMMA) blends and PS-polytetrafluoroethylene PMMA copolymers [76], cyanate ester resin-carbon fibre composites [77], polycyanate epoxy resins [78], and styrenic copolymers [79]. 

Studies on randomness of filler distribution in polymethylacrylate nanocomposite are interesting. In this experiment, siUca particles were formed both before and after matrix polymerization. The results indicated that the concentration of silica was a controlling factor in the stress-strain relationship rather than the uniformity of particle distribution. Also, there was no anisotropy of mechanical properties regardless of the sequence of filler formation. This outcome cannot be expected to be duplicated in all other systems. For example, when nickel coated fibers were used in an EMI shielding application." When compounded with polycarbonate resin, fibers had a much worse performance than when a diy blend was prepared first and then incorporated into the polymer (Figure 7.1). In this case, pre-blending protected the fiber from breakage. 

In the present chapter, the modulation of the final properties of a nanocomposite containing cellulosic nanoreinforcement combined with a second filler, will be analyzed and reported. In this way, the properties of the final materials can be adjusted as a function of the particle size and distribution, shape, as well as by their interactions with the cellulose surface. The effect of the second reinforcement will be considered for a wide variety of potential applications, including network structures for tissue engineering, antimicrobial films, electronics, protective coatings, barrier/filter membrane systems. 

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