As a flexible protective material, shear thickening gel (STG)/Kevlar composite still has great potential to improve its impact resistance. In this paper, a novel STG/SiO 2 /Kevlar flexible protective composite was prepared by impregnating STG/SiO 2 into Kevlar. Due to the excellent SiO 2 enhancement effect, the STG/SiO 2 /Kevlar exhibited a higher safeguarding property than the STG/Kevlar.The maximum yarn pull-out force of STG/SiO 2 /Kevlar reached 61.7 N, which was higher than the 41.9 N of STG/Kevlar. The uniform puncture results showed that the maximum bearing capacity of STG/Kevlar and STG/SiO 2 /Kevlar increased by 116.8% and 215.3%, respectively, compared with pure Kevlar. The impact test results indicated that 20 layers of STG/SiO 2 /Kevlar could not be penetrated by the knife stab and 24 layers of STG/SiO 2 /Kevlar could not be penetrated by 7.62 mm pistol bullets. Finally, the enhancement mechanism of impact resistance of STG/SiO 2 /Kevlar composites was studied.

In order to meet the requirements of practical applications, the shape effect of particles and their shear‐thickening mechanism is very crucial to the shear thickening gels (STG). In this work, three kinds of STG/particle composites were successfully prepared by blending nanoscale SiO2, microscale MWCNTs, and millimeter‐scale carbon fiber in STG. The Rheological Property, compression, and impact resistance of STG/particle composites were tested and analyzed. The results showed that the enhancement of the shear‐thickening properties of STG by nanoparticles was more pronounced than that of micrometer and millimeter‐sized particles. Nanoscale SiO2 significantly improved the storage modulus of STG, the G'max of STG/6%SiO2 increased by 124.63% compared with pure STG. Nanoscale SiO2 also had a great enhancement effect on the compression resistance of STG, the bearing capacity of STG/6%SiO2 and STG increased by 7.7 and 4.5 times. Furthermore, the energy absorption of STG/6%SiO2 and STG increased by 545% and 282% respectively. The drop hammer impact test also showed that STG/6%SiO2 had the best impact resistance. In addition, a possible mechanism of shear‐thickening properties of particle‐enhanced STG was proposed.