Preparation and characterization of red mud/liquid silicon rubber with good thermal-stability and processability

As reported herein, a novel addition-type liquid silicone rubber (LSR)/red mud (RM) composite has been synthesized. Triethoxyvinylsilane (KH151) was used as a surface modification agent to treat RM and form hydrophobic surfaces. The optimal formulation of the composite was determined by the mechanical properties of the LSR that were prepared at different crosslinker and filler contents. The reinforcement mechanism of modified RM on LSR was revealed by combining Fourier transform infrared (FTIR) spectroscopy, x-ray photoelectron spectroscopy and mechanical property tests. Thermal degradation behavior of RM/LSR at elevated temperature was investigated by the thermogravimetric analysis (TG), TG-FTIR and alteration of mechanical properties after thermal aging. The results of the experiment indicate that modified RM increased the tensile strength and Young's modulus of LSR dramatically and provides superior thermal stability to the LSR. With 100 phr RM added, the tensile strength of RM/LSR composite was almost 12 times greater than that of pure LSR, and pure LSR degrades completely after aging at 300? for 24 h while RM/LSR retains its mechanical properties.

Automated summary

In this study, a novel addition-type liquid silicone rubber (LSR)/red mud (RM) composite was synthesized. The modified RM showed enhanced mechanical properties and thermal stability to LSR. The addition of modified RM significantly increased the tensile strength and Young's modulus of LSR, while retaining its mechanical properties after thermal aging.