Exploring Ag-doped Mullite as High Dielectric and Antimicrobial Reinforcement with Polybenzoxazine Matrix

The present work describes the development of high k dielectric aluminosilicate and its application as reinforcement with polybenzoxazine matrix to achieve high dielectric and antimicrobial nanocomposite. Initially, dielectric constant value of mullite was found to increase with respect to the percentage of Ag in mullite lattices and reached a maximum of 14.9, when doped with 5?mol%. Data from antimicrobial assay also suggest that, the zone of inhibition expands with respect to embedding silver, and thus 10?mol% of Ag-doped mullite exhibiting the highest antimicrobial property. Since, 3?mol% Ag-doped mullite hold better dielectric, various weight percentages of the same (MA₃) were embedded with polybenzoxazine matrices after its surface modification. Among the resulted nanocomposite, 1.5% of glycidyl-functionalized MA₃/polybenzoxazine not only showed remarkable enhancement in their thermal, dielectric, electrical conductivity but also exhibited a zone of inhibition of 11 and 12?mm against Escherichia coli and Pseudomonas aeruginosa, respectively. The enhanced thermal, dielectric, and antimicrobial properties will make this material as a suitable candidate in printed circuit board application in particularly for cold weather climatic conditions.