Mechanical, thermal conductive and dielectrical properties of organic montmorillonite reinforced benzoxazine/cyanate ester copolymer for electronic packaging

In this work, benzoxazine/bismaleimide/cyanate ester (BOZ/BMI/BADCy) was prepared by bisphenol A benzoxazine, bisphenol A dicyanate, 4, 4′-bismaleimidodiphenyl methane, and organo-modified 2D montmorillonite (OMMt) nanoparticles. OMMt was synthesized and characterized using FTIR. The effect of different weight fraction of OMMt (0–5 wt%) on the dielectric, thermal, mechanical properties of the composites was investigated. All composites exhibited excellent dielectric properties and thermal stability endowed by BOZ/BMI/BADCy matrix. OMMt improves their dispersibility, alignment and interfacial strength and hence electrical conductivity and real permittivity increase with increasing OMMt loading, and a suitable addition of OMMt can enhance the mechanical properties, dielectric strength as well as reduce the dielectric loss of BOZ/BMI/BADCy terpolymer. The dielectric constant and dielectric loss of the sample with 4 wt% of OMMt filler was 3.56 and 0.004, at 1 kHz. The dielectric constant of the composites showed only a very small variation with frequency in the range 100–1 MHz. All these changes in properties are closely correlated to the OMMt/BOZ/BMI/BADCy nanocomposites, which could form an interaction interface structure in the system.