Morphology characterization, filler structure

Analyzing the morphology of an elastomer includes not only the characterization of the molecular structure of the polymer itself and of the compounding ingredients, but may also extend to the supermolecular scale. Such a characterization includes filler network structure (see Chapter 8), the phase... 

In Part Two, Chapter 4 describes a general fabrication-characterization route of electrospinning PLA poly(s-caprolactone) (PCL)/HNT composite fibers. The effects of HNTs with or without the modifier 3-aminopropyltriethoxysilane on fiber diameter, morphological structure, thermal properties, crystalline stmctures, and degree of crys-talhnity, as well as the intermolecular interaction of electrospun nanocomposite fibers, are thoroughly studied to provide the appropriate guidance to the controlled drug release associated with fibrous structures. Chapter 5 deals with the synthesis and characterization of CNT hybrid fillers via chemical vapor deposition (CVD) technique for polymer nanocomposites. Optimized synthesis parameters are presented and comparative studies are also conducted between chemical hybrid-filled and physical hybrid-fiUed polymer nanocomposites in terms of their typical applications. 

Discussion - The morphological properties of active fillers are important aspects of rubber reinforcement. The structure of the reinforcing filler is characterized by aggregates of primary particles, which form cavities for attachment and penetration of polymer molecules. The SEM pictures show that the three-dimensional morphology is basically maintained. 

As will be demonstrated later, morphology and physicochemical properties of reinforcing fillers are of crucial importance because they directly define their reinforcement ability. Their characterization formerly was based essentially on morphological properties (surface area and structure), but because of the use of silicas as reinforcing filler, there is now a strong need for dispersibility and surface chemistry characterization. 

From a practical point of view, an accurate morphological characterization of the filler dispersion allows us to ascertain the homogeneity of the filler network, responsible for the material s performance, as well as to detect structural differences in the filler aggregates and to relate them to the final properties of the composite material. 

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