Polymer-filler composition

Polymer-Filler Composites thru In Situ Graft Copolymerization Polyethylene-Clay Composites... 

Two procedures were used to prepare compatibilized polymer-filler composites ... 

In any preparation of polymer-filler composites, there is concern about the quality of adhesion at the filler/matrix interface, and consequently over the interaction between filler and molten polymer at the compounding stage. Various technologies have been proposed to enhance adhesion in our laboratories, we have developed surface treatment (encapsulation) techniques in which mica is exposed to a "cold" microwave plasma (l.e. Tgiectron Tgas "Large Volume Microwave Plasma Generator"(LMP)... 

Figure 3.38 shows that reaction between Al(0H)3 and dicarboxylic acid anhydride affects the sedimentation volume of filler.The limiting value of sedimentation was obtained by modifying the filler surface with a monolayer of a suitable modifier. A similar modification affects the performance of this filler in polymer-filler composites. Thus, different properties were affected by the surface coverage of filler and by the filler-matrix interactions. 

Table VII Optical Clarity of Polymer/Filler Composition Silica...

The behavior of nanocomposites, in which the filler can interact with the host polymer via specific secondary interactions, is similar to that of the hydrogen-bonded blends, but may have even greater potential for reducing aging rates. Nanocomposites also have several advantages over the blends, such as the use of common polymers that require little or no chemical modification, the ability to vary the polymer-filler composition relatively easily, and the ready availability of economical filling materials. Clearly, this group of materials deserves further study. 

Clays are strongly hydrophilic in nature, making their dispersion in organic matrices difficult [26]. There are usually three possible arrangements of these layered silicate clays, which can be obtained when they are dispersed in a polymer matrix. If the polymer cannot intercalate between the silicate sheets, a non-intercalated microcomposite is obtained. Beyond this traditional class of polymer-filler composites, two other types of composites can be obtained. An intercalated structure is one in which the separation of clay layers occurs to some extent by increasing the interlayer spacing. 

Gaylord, N.G., Ender, H., Davis, L Jr., and Takahashi, A. (1979) Polymer-Filler Composites Thru In Situ Graji Copolymerization Polyethylene — Clay Composites, ACS Symposium Series 121 (eds C.E. Carraherjr. and M. Tsuda), American Chemical Sodety, Washington, DC, pp. 469-474. 

For the case of the mixture (polymer-filler composition), subscripts 2 and 3 are used to represent the first and second mixtures components, and Eq. (10.11) can be rearranged as [33,34] ... 

Milczewska, K. and Voelkel, A. (2008) Use of Flory-Huggins parameters in the characterization of polymer-filler compositions. J. Appl. Polym. Sci., 107, 2877-2882. 

Ning N, Fu S, Zhang W, Chen F, Wang K, Deng H, et al. Realizing the enhancement of interfacial interaction in semicrystalline polymer/filler composites via interfacial crystallization. Prog Polym Sci 2012 37 1425-55. 

Beyond this traditional class of polymer-filler composites, two types of nanocomposites can be obtained. Intercalated structures are formed when a single (or sometimes more) extended polymer chain is intercalated (sandwiched) between the silicate layers. The result is a well-ordered multilayer structure of alternating polymeric and inorganic layers. Exfoliated or delaminated structures are obtained when the silicates are completely and uniformly dispersed in the continuous polymer matrix. The delamination configuration is of particular interest because it maximizes the polymer-clay interactions, making the entire surface of the layers available for the polymer. This should lead to the most significant changes in mechanical and physical properties. A schematic of the types of possible structure formations in PC composites is depicted in Fig. 13.2. 

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