Surface modification nano-CaCO

SEM is also a useful tool for evaluation of interfacial interactions. If severe agglomeration occurs, debonded agglomerates and holes may be observed on fractured surfaces of polymer/nano-CaCOs composites, which is a sign of extremely poor interfacial adhesion. When agglomerates are small and the majority of agglomerates are embedded in the matrix on the fractured surface, a sharp interface boundary also implies weak interfacial adhesion between the two phases. Sharp interfacial boundaries can be observed clearly under SEM even if a predominantly nanometer-scale dispersion of CaCOs is achieved, and it is a distinctive morphological feature for most melt-compounded polymer/nano-CaCOs systems. In contrast, with adequate surface modification of nano-CaCOs,... 

Polymer/CaCOs nanocomposites have developed rapidly in the past few years. Cubic nano-CaCOs particles with narrow size distribution can now be produced on a massive scale at relatively low cost. Nanometer-scale dispersion of CaC03 particles in common polymer matrices has been successfully achieved via in-situ polymerization and/or melt-compounding with the aid of organic modification of filler surface. The nanocomposites fabricated possess a combination of good mechanical properties, processability and improved temperature resistance at... 

Filler surface modification and nanocomposite fabrication. Agglomeration of nano-CaC03 in the surface modification process has remained a major problem because of the enormous interfacial area of the nanoparticles. The uniform dispersion of nano-CaCOs in polymer precursors and melts, therefore, still presents a key challenge for the in-situ polymerization and melt compounding approaches. Carefully engineering and fiill understanding of interfacial properties are needed, and ultimately many perspectives will develop, dictated by the final applications of each specific system. 

In this chapter, the study carried out on nanofillers reinforced natural/synthetic rubber has been discussed. After a description on the NR rubber and CaCOs as filler, the development of synthetic composites with the incorporation of micro and nano-CaC03 as a filler material has also been discussed for comparative study. In particular, the role of fillers on the property modification of rubber properties, such as surface properties, mechanical strength, thermal conductivity, and permittivity has been mentioned. The effectiveness of this coating was demonstrated. The importance of well-dispersed nanoparticles on the improvement of the mechanical and electrical properties of polymers is also emphasized. However, one of the problems encountered is that the nanoparticles agglomerate easily because of their high surface energy. 

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