Nanocomposites solution casting method

Pillai et al. described a comparison between two chemical functionalization strategies for the amine functionalization of multiwalled CNTs. The modified CNTs with optimum amine content were used to prepare PLA/CNT nanocomposites through solution casting method. The polymer nanocomposite thus prepared showed improved thermal properties when compared to the neat PLA [65]. 

Nitrile-functionalized graphene/PEN nanocomposites were prepared by an easy solution casting method [48]. 

The art of filler dispersion in polymer matrix is easily determined by X-ray analysis especially WAXS analysis. The intensity and position of X-ray diffraction peaks reveals the exact idea regarding the morphological structure of polymer nanocomposites. Figure 22.11 compares reduced graphite oxide dispersions in NR matrix by different processes such as milling and solution casting methods. 

Zhijiang et al. reported an improvement in the mechanical properties of a PHB nanocomposite made of bacterial cellulose nanofibrils that was prepared by the solution casting method. In addition, they found that the nanocomposite showed better biocompatibility and mechanical properties than pure PHB based on cell-adhesion analysis using Chinese hamster lung (CHL) fibroblast cells and stress strain tests, respectively. In comparison to pure PHB, the nanocomposite of PHB/bacterial cellulose was observed to exhibit about a 202% increase in tensile stress and a 2.2-fold increase in elongation to break, respectively (Figure 5.3). ... 

Casting is one of the most common techniques for processing lab scale starch composites. Different types of polysaccharide nanofillers such as cellulose from flax, wood, hemp ramie, cassava bagasse, wheat straws, starch from waxy maize, regular maize, and chitin, chitosan, among others were used to fabricate starch nanocomposites by the solution casting method. 

In this work, the starch/PVOH/silicate clay blend films were prepared by a solution casting method. Four different types of layered silicate clays were used to investigate the compatibility of multiphased system. Special attention is driven to study the effect of the clay content on the film properties based on barrier and mechanical modeling predictions of nanocomposite films. 

An SPE composed of a three-dimensional crosslinked compound, using a diacrylic acid ester compound and/or a dimethacrylic acid ester compound, was reported for use in electrochemical devices. Nanocomposite SPE films composed of PEO, lithium triflate (LiCEgSOs) and Si02 nanofiller (15 nm in size) were prepared by using the solution-cast method. At room temperature, PEO-LiCFsSOs (88 12 w/w) showed a high ionic conductivity of about 1.28 x 10 S/cm. 

Fabrication methods have overwhelmingly focused on improving nanotube dispersion because better nanotube dispersion in polyurethane matrix has been found to improve the properties of the nanocomposites. The dispersion extent of CNTs in the polyurethane matrix plays an important role in the properties of the polymer nanocomposites. Similar to the case of nanotube/solvent suspensions, pristine nanotubes have not yet been shown to be soluble in polymers, illustrating the extreme difficulty of overcoming the inherent thermodynamic drive of nanotubes to bundle. Therefore, CNTs need to be surface modified before the composite fabrication process to improve the load transfer from the polyurethane matrix to the nanotubes. Usually, the polyurethane/CNT nanocomposites can be fabricated by using four techniques melt-mixing (15), solution casting (16-18), in-situ polymerization (19-21), and sol gel process (22). 

In solvent casting or solution mixing, CNTs are first dispersed in a suitable solvent and then mixed with a polymer solution to obtain a suspension of nanotubes in the polymer. The mix is then poured into suitable die molds and the solvent is allowed to evaporate to leave behind nanocomposite film. Solution based methods offer advantages of lower viscosities which facilitate uniform mixing and dispersion. Ultrasonication or magnetic stirring is typically used to separate and disperse CNTs uniformly in different solvents or... 

Nanocomposites are materials in which nanoparticles (in this case, nanorods) are dispersed in a continuous matrix. The matrix may be a polymer, nanorods, or other nanoparticles. Nanorod composites find applications in diverse areas such as efficient charge storage, removal of contaminants (e.g. surfactant) from water, emissivity control devices, and metallodielectrics, and so on. A number of methods such as electroless deposition, the sol-gel method, the hydrothermal method, solution casting, carbother-mal reduction, the template-based method, the sonochemical method, and electrospinning can be used to prepare composite nanorods. Nanorod composites are different from core-shell nanorods. In core-shell nanorods, the coating is uniform, whereas in the nanorod composite (consisting of a nanorod and a nanoparticle on a surface), fine nanoparticles are dispersed on the surface of the nanorods. Some specific examples of the preparation of nanocomposites consisting of nanorods are described below. 

Other nano-fillers have also investigated. Cao et al. [253] reported the utilization of multiwalled carbon nanotubes (MWCNTs) as filler-reinforcement to improve the performance of plasticized starch (PS). The PS/MWCNTs nanocomposites were prepared by a simple method of solution casting and evaporation. The results indicated that the MWCNTs dispersed homogeneously in the PS matrix and formed strong hydrogen bonding with PS molecules. Besides the improvement of mechanical properties, the incorporation of MWCNTs into the PS matrix also led to a decrease in the water sensitivity of the PS-based materials. 

To obtain a uniform dispersion in the rubbery matrix, different processing methods like solution casting, latex blending, two-roll mill mixing, melt mixing etc. have been attempted. However, two methods are popularly used to prepare nanocomposites of NR and have been discussed in detail in a recent review on chitin whiskers. 

When obtaining PLA/clay nanocomposites, three main techniques are frequently used to produce nanocomposites of this material, namely in situ intercalative polymerization, solution-casting and melt mixing. Of the three, the in situ intercalative polymerization method exhibits the highest performance, since it is the one that results in a higher degree of interaction... 

Solution casting has been widely used as a nanocomposite processing method since solvent intercalation is the simplest way to prepare PLA/clay nanocomposites. But, a solvent where polymer is soluble and nanofillers are highly dispersible is necessary. The preparation of PLA-based nanocomposites by this method normally results in good dispersion of the nanofillers within the polymer matrix, and consequently in enhanced properties, as has successfully been demonstrated by some authors. 

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