STUDY ON CONDUCTIVITY OF 2 KINDS OF CROSS-LINKED POLYETHER SOLID ELECTROLYTES AND ELECTRORHEOLOGICAL PROPERTIES OF ANHYDROUS SUSPENSIONS BASED ON THEM

Two kinds of cross-linked polyether solid electrolytes (CPESE) with hi gh ionic conductivity (a) of 8.0x10(-5) S cm(-1) (25 degrees C, for do uble ionic conducting CPESE2) or 4.0x10(-6) S cm(-1) (30 degrees C, fo r single ionic conducting CPESE1) were obtained by polymerizing alpha, omega-bismethacryloyl capped poly(ethylene glycol) (BMAPEG) after comp lexing with LiClO4 or copolymerizing BMAPEG with salt of methacrylic a cid (MAAM), respectively. In the mean time, the CPESE based anhydrous electrorheological (ER) fluids with relatively high activity were dire ctly synthesized by inverse suspension polymerization of BMAPEG after complexing with LiClO4 or of BMAPEG with MAAM. The influences of struc ture of CPESE on their conductivity and properties for ER fluids based on them were studied. The results showed that maximum a occurred at a n optimum molecular weight of poly(ethylene glycol) segment (M-PEG) as well as a certain value of [Li+]/[EO] or [MAAM]I[EO], while a decreas ed with increasing functionality of BMAPEG (f). For ER fluids containi ng CPESE2, yield stress ( tau(s),) increased with f while tau(s) showe d a maximum value at a certain [Li+]/[EO]. Leak current density (J) in creased with increasing [Li+]/[EO] or with decreasing f. A maximum J o ccurred with change of MPEG For ER fluids containing CPESE1, both tau( s) and J showed a maximum value with increasing M-PEG or [MAAM]/[EO], while tau(s) and J decreased with increasing f. tau(s) hardly depended on the type of its counterion, while J decreased in the following cou nterion order: K+ approximate to Li+ > Na+. (C) 1998 Elsevier Science Ltd. All rights reserved.