Synthesis and characterization of polybenzoxazine based matrices and nanocomposites

Abstract

The objective of the present work is to study the synthesis and characterization of new types of polybenzoxazine based matrices and nanocomposites and to improve their thermal, mechanical and dielectric properties to utilize them for high performance applications. The polybenzoxazine nanocomposites were developed from different types of benzoxazine derivatives and were hybridized with nano-sized organically modified montmorillonite clay (OMMT), polyhedral oligomeric silsesquioxane and mesoporous SBA-15. The benzoxazine derivatives, nanofillers such as organoclay, POSS derivatives and benzoxazine functionalized SBA-15 were prepared, characterized and utilized for the present work. Data obtained from differential scanning calorimetric analysis indicate that the synthesized benzoxazine monomers undergo curing at lower temperature when compared to that of conventional benzoxazine monomers. The photo irradiated cured products were found to possess higher glass transition temperature and increase in thermal stability with an increase in photo irradiation time has also been observed. The dielectric properties of organoclay as well as POSS reinforced PBZ nanocomposites were determined using impedance analyzer and the results indicate that the POSS reinforced PBZ shows lower dielectric constant than that of the organo clay reinforced PBZ due to the less polar nature of POSS. The morphological properties of the POSS/ polybenzoxazine nanocomposites were studied by XRD, SEM and TEM. An increase in weight percentage of BZ/SBA-15 into PBZ matrix seems to improve the glass transition temperature, thermal stability and dielectric behaviour. Studies on polybenzoxazine matrices and polybenzoxazine nanocomposites developed in the present work indicate that these hybrid materials can be used in the form of coatings, films, sealants, encapsulants, adhesives, matrices and composites for varying range of industrial and engineering uses including microelectronic applications for better performance and longevity. newline newline newline