A novel magnetorheological-polyethylene glycol shear thickening gel based on a lower temperature-sensitive gel matrix

A novel polyethylene glycol shear thickening gel (PSTG) with lower temperature sensitivity is developed to prepare a magnetorheological-PSTG (MR-PSTG). An evaluation system for temperature-sensitive characteristics is proposed with indicators named the thermal relative effect constant (α) and the temperature coefficient of the relative effect (TCRE), which depict the physical properties and change rate of the relative shear thickening effect (RSTE), respectively. The mechanism of the reduction in temperature sensitivity is analyzed through Fourier transform infrared spectroscopy and x-ray photoelectron spectroscopy. Finally, the RSTE and relative MR effect (RMRE) of MR-PSTG are investigated under different mass fractions of carbonyl iron powder (CIP). At temperatures ranging from 5 °C to 65 °C, the α of STG is a maximum of 162% greater than that of PSTG. The TCRE of PSTG decreases with increasing temperature, with a minimum of 0.016 25 and a maximum of 0.070 02. The new molecular chains in PSTG form a more compact and stable cross-linked network, which leads to a decrease in the temperature sensitivity of PSTG. The maximum RSTE and RMRE values of MR-PSTG based on PSTG-400 are 12 418.18 and 31.42, which correspond to CIP mass fractions of 20% and 30%, respectively.