Use of Polymer Composites in Photonic Applications

Ordered macroporous materials (OMMs) are a new family of porous materials that can be synthesized by using colloidal microspheies as the template. - The most unique characteristics of OMMs are their uniformly sized macropores arranged at micrometer length scale in three dimensions. Colloidal microspheres (latex polymer or silica) can self assemble into ordered arrays (synthetic opals) with a three-dimensional crystalline structure. The interstices in the colloidal crystals are infiltrated with a precursor material such as metal alkoxide. Upon removal of the template, a skeleton of the infiltrated material with a three-dimensionally ordered macroporous structure (inverse opals) is obtained. Because of the 30 periodicity of the materials, these structures have been extensively studied for photonic applications. In this paper, the synthesis and characterization of highly ordered macroporous materials with various compositions and functionalities (silica, organosilica, titana, titanosilicate, alumina) are presented. The application potential of OMMS in adsorption/separation is analyzed and discussed. 

Titania (Ti) is another promising partner for the polymer in hybrid composites that are useful for photonic applications because of its high refractive index. When Ti02 is obtained by the sol-gel method, however, it is not easy to prepare hybrid composite thin films of Ti with polymers because of the fast hydrolysis reaction and thus the extremely fast gelation of titanium aUcoxide. Therefore, only a few studies have been reported that describe polymer-Ti composites. Instead, attempts to form composites... 

Liquid crystalline polymer composites have become an increasingly important material for technological field involving photonic applications. Several attractive features such as dielectric anisotropy present in the mesophase, reasonably wide temperature range, low thermal expansion coefficient, high chemical resistance, specific thermo-mechanical response etc. make them more attractive. Of comse several limitations have to overcome in order to avail the total benefit of using such materials for opto-electronic applications. 

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