Nanofillers three-dimensional

Polyhedral oligomeric silsesquioxane (POSS) has been described as a three-dimensional "cage-shaped molecule composed of a silicon-oxygen framework bonded to organic groups that make it compatible with a polymer matrix. Unlike conventional nanofillers that must be dispersed and exfoliated to be useful, POSS molecules formulated in the resin are induced by shear to "self-assemble ... 

Abstract This chapter describes the influence of three-dimensional nanofillers used in elastomers on the nonlinear viscoelastic properties. In particular, this part focuses and investigates the most important three-dimensional nanoparticles, which are used to produce rubber nanocomposites. The rheological and the dynamic mechanical properties of elastomeric polymers, reinforced with spherical nanoparticles, like POSS, titanium dioxide and nanosdica, were described. These (3D) nanofillers in are used polymeric matrices, to create new, improved rubber nanocomposites, and these affect many of the system s parameters (mechanical, chemical, physical) in comparison with conventional composites. The distribution of the nanosized fillers and interaction between nanofUler-nanofiUer and nanofiller-matrix, in nanocomposite systems, is crucial for understanding their behavior under dynamic-mechanical conditions. 

The focus of this chapter is to present three-dimensional nanofillers and the influence of these kinds of nanoparticles on the nonlinear viscoelastic behavior of rubber nanocomposite systems. 

Figure 1 presents the typical geometries of the nanodimensional fillers which are commonly used to modify the elastomeric matrix [5], Nanoparticles possess many shapes and sizes (Fig. 1), but primarily they have three simple geometric forms sphere, cylinder and plate type. Three-dimensional nanofillers (3D) are relatively equiaxed particles, smaller than 100 nm (often below 50 nm [6]), e.g. nano SiOa, Ti02. These nanoparticles are described in the Sects. 2.2-2.4. Sometimes in the literature, the term 3D nanofillers (spherical) is described as a zero-dimensional (OD) system, but actually OD nanofillers are represented by POSS molecules, fullerenes, crystals or quantum dots [6]. What s more, very often the term physical form of these nanoparticles is referred to as agglomerates . The dispersion of particles from agglomerates to nanoparticles seems to be a big challenge to all... 

Rubber nanocomposites have attracted great interest for the past few years due to their unique physical and chemical properties [17]. The properties of rubber nanocomposites can be modified with various nanoparticles. There are a lot of types and shapes of the nanofillers like silica, Ti02, POSS, nanocrystals, other oxides (three-dimensional) carbon nanotubes, metallic fibers (two-dimensional) and clays, modified clays or graphene (one-dimensional). 

The treatment of an epoxy polymer as a natural nanocomposite or quasi-two-phase system [8] puts in the foregroimd the interaction of such system components, which for nanocomposites is expressed first of all in an interfacial regions formation [2-4]. Let us note that in the reinforcement process (increase in the elasticity modulus of the nanocomposite in comparison with the matrix polymer) interfacial regions play the same role as the nanofiller [2-4], Such a reinforcement mechanism is due to the formation of nanocomposites with inorganic nanofiller [1-A and the structure of natural nanocomposites (linear amorphous polymers) [9] in three-dimensional Euclidean space. Therefore in paper [10] the study of structure formation conditions for crosslinked epoxy polymers, treated as natural nanocomposites, was carried out within the frameworks of fractal analysis. 

There is a wide variety of both synthetic and natural crystalline fillers that are able, under specific conditions, to influence the properties of PP. In PP nanocomposites, particles are dispersed on the nano-scale. " The incorporation of one-, two- and three-dimensional nanoparticles, e.g. layered clays, nanotubes, nanofibres, metal-containing nanoparticles, carbon black, etc. is used to prepare nanocomposite fibres. However, the preparation of nanofilled fibres offers several possibilities, such as the creation of nanocomposite fibres by dispersing of nanoparticles into polymer solutions, the polymer melt blending of nanoparticles, in situ prepared nanoparticles within a polymeric substrate (e.g. PP/silica nanocomposites prepared in situ via sol-gel reaction), " the intercalative polymerization of the monomer. 

Depending on nanoparticle shape, the nanoplatelets, nanofibers, and nanopowders are classified as one-, two-, or three-dimensional nanofillers, respectively. 

In the last few years, a large variety of organic and inorganic nanofillers of various shapes and sizes have been used to prepare SR nanocomposites. They can be classified into zero dimensional (OD), one dimensional (ID), two dimensional (2D) and three dimensional (3D) fillers. Recently, layered double hydroxides (LDHs) have also received more attention as new generation 2D nanofiller in the preparation of polymer nanocomposites with a lot of promise. 

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. 

There is a general agreement that nanocomposites imply nanoscale fillers with sizes less than 100 nm in at least one dimension. The fillers can be classified into three groups depending on their shape. One-dimensional nanofillers are nanorods, fibers, or tubes with varying aspect ratios. Rodlike nanopartides can introduce anisotropic properties to composite materials, for example, silver or gold nanorods are used for preparation of dichroic nanocomposites as described later (Figure 1). 

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