The Electrorheological Performance Research Of Surfactant Modified Attapulgite Clay

Electrorheological fluids acted as an important kind of intelligent materials. Because of the excellent performance, the anhydrous inorganic electrorheological fluid has always been paid attention to since the electrorheological fluid was discovered by Winslow in 1947. At present, most of researchers focusing on the dispersed phase particles, especially modified by surfactant which process is simple and the performance is superior. Therefore, dispersed phase, which modified in suitable way for electrorheological materials, has been widely researched.This article selects three sorts and nine kinds of surfactants to modified attapulgite(AT), the modified attapulgite crystal structure, chemical structure and microstructure had been researched; Moreover the modified attapulgite as disperse phase was prepared by electrorheological fluid and the electrorheological property, dielectric property and electric conductivity, thermal stability and suspension property has been tested. The specific research work and main conclusions are as follows:(1) Three kinds of cationic surfactant has been selected, dodecyl trimethyl ammonium bromide(DTAB), myristyl trimethyl ammonium bromide(TTAB) and cetyl trimethyl ammonium bromide(CTAB), in order to modified attapulgite by situ polymerization. And then, the result of the comparison shows that the most suitable cationic surfactant is CTAB after compare the influence of the carbon chain length and volume fraction on electrorheological effect. The methods of chemical element analysis, FTIR, XRD, SEM, four probe technique and digital LCR digital bridge has been used to analyze the material structure and its performance. Discussing the test of the surfactant concentration, volume fraction, temperature on the properties of electrorheological effect and the suspension performance of electrorheological fluid which dispersed phase particles is acted by CTAB modified AT. The result shows that the optimal concentration of CTAB modification AT is 0.2 mol/L, the best volume fraction is 20 Vol.% while the electrorheological fluid is consist of modified particles and dimethyl silicone oil, and the maximum of shear stress is 169 Pa and yield stress reaches 0.65 Pa in the E=3.5kV/mm. What’s more, the highest working temperature is 65 ℃, and the suspension rate reaches 90% after stand for 60 days.(2) There are three kinds of anionic surfactant has been selected, dodecyl benzene sulfonic acid(DBSA), sodium dodecyl benzene sulfonate(SDBS) and sodium dodecyl sulfate(SDS), in order to modified attapulgite. The optimal anionic surfactant is DBSA. The methods of chemical element analysis, FTIR, XRD, SEM, four probe technique and digital LCR digital bridge has been used to analyze the material structure and its performance. Discussing the test of the surfactant concentration, volume fraction, temperature on the properties of electrorheological effect and the suspension performance of electrorheological fluid which dispersed phase particles is acted by DBSA modified AT. The result shows that the optimal concentration of DBSA modification AT is 0.2 mol/L, the best volume fraction is 20 Vol.% while the electrorheological fluid is consist of modified particles and dimethyl silicone oil, and the maximum of shear stress is 153 Pa in the E=3.0kV/mm, and the suspension rate reaches 91% after stand for 60 days.(3) Three kinds of nonionic surfactant has been selected, polyethylene glycol 400(PEG400), polyethylene glycol 600(PEG600) and polyethylene glycol 1200(PEG1200), in order to modified attapulgite by situ polymerization. The optimal nonionic surfactant is PEG1200. The methods of chemical element analysis, FTIR, XRD, SEM, four probe technique and digital LCR digital bridge has been used to analyze the material structure and its performance. Discussing the test of the surfactant concentration, volume fraction, temperature on the properties of electrorheological effect and the suspension performance of electrorheological fluid which dispersed phase particles is acted by PEG1200 modified AT. The result shows that the optimal concentration of PEG1200 modification AT is 0.2 mol/L, the best volume fraction is 20 Vol.% while the electrorheological fluid is consist of modified particles and dimethyl silicone oil, and the maximum of shear stress is 142 Pa in the E=3.5kV/mm, and the suspension rate reaches 87% after stand for 60 days.