Antistatic effects and mechanism of ionic liquids for methyl vinyl silicone rubber

The effect of two ionic liquids (ILs), namely, 1-allyl-3-methyl imidazolium chloride ([AMIM]Cl) and 1-ethyl-3-methyl imidazolium tetrafluoroborate ([EMIM]BF4), on the surface and volume resistivities, mechanical properties, transparency, and water contact angle of methyl vinyl silicone rubber (MVQ) were investigated. The chemical structures of the two ILs before and after heat treatment were characterized by Fourier transform infrared spectroscopy. The morphology and fluorine and chlorine elemental dispersion were characterized by field emission scanning electron microscopy and energy-dispersive X-ray spectroscopy mapping, respectively. The antistatic mechanism was revealed. The results show that the MVQ–[EMIM]BF4 composites had lower surface and volume resistivities than the MVQ–[AMIM]Cl composites. The mechanical properties of the MVQ–[EMIM]BF4 and MVQ–[AMIM]Cl composites were slightly lower than those of the pristine MVQ. With increasing [EMIM]BF4 content, the surface and volume resistivities and water contact angle of the MVQ–[EMIM]BF4 composites decreased. When the content of [EMIM]BF4 was 2.0 phr, the MVQ–[EMIM]BF4 composites showed better antistatic performance with lower surface and volume resistivities of 9.6 × 109 Ω and 1.2 × 1011 Ω cm, respectively. The antistatic mechanism of the MVQ–IL composites was ascribed to the synergistic effect of ionic migration and moisture absorption. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2017