Performance of SiO2 Filled Functional Polypropylene Substrates for 5th Generation Communication

Abstract

Three grades of functional polypropylene (FPP)/silica (SiO2) (FPPASP16 xSiO2 y, FPPASP17 xSiO2 y and FPPASP18 xSiO2 y) and their crosslinked FPP/SiO2 (CLFPPASP16 xSiO2 y, CLFPPASP17 xSiO2 y and CLFPPASP18 xSiO2 y) nanocomposites were satisfactorily made for applying as fifth generation (5 G) mobile communication substrates. Significantly smaller linear thermal expansion coefficient (LCTE) but larger dielectric constant (εr), dielectric loss (tan δ) and onset degradation temperature (DTonset) were acquired for CLFPPa xSiO2 y than those of the corresponding FPPa xSiO2 y sequence having identical SiO2 loadings. It is worth emphasizing that substantially smaller εr, tan δ and LCTE values were acquired for every FPPa xSiO2 y and CLFPPa xSiO2 y sequence filled with appropriate SiO2 loadings. Quite small εr/tan δ ( 2.41/0.00539, 2.36/0.00361, 2.53/0.00653, 2.52/0.00671, 2.46/0.00461 and 2.62/0.00821, all measured at 1 MHz) and LCTE (∼140 ppm/°C, 152 ppm/°C, 75 ppm/°C, 127 ppm/°C, 142 ppm/°C and 56 ppm/°C) values suitable for 5 G communication were acquired for FPPASP16 95SiO2 5, FPPASP17 94SiO2 6, FPPASP18 95SiO2 5, CLFPPASP16 95SiO2 5, CLFPPASP17 94SiO2 6 and CLFPPASP18 95SiO2 5 filled with optimum loadings of SiO2 nanoparticles, respectively. All free volume properties estimated for every FPPa xSiO2 y and CLFPPa xSiO2 y sequence enlarged to a largest value as the SiO2 loadings approached the corresponding optimum value. Possible reasons accounting for these substantially diminished dielectric and LCTE and improved thermal degradation properties of the FPPa xSiO2 y and CLFPPa xSiO2 y films are proposed.