High-Performance Impact-Resistant Shear-Thickening Gel Composites Enabled by Optimally-Dispersed Carbon Nanotubes

This study addresses persistent issues of cold-flow deformation, sluggish shear-thickening response, and poor energy dissipation in shear-thickening gels (STGs) through solvent-assisted integration of optimally dispersed carbon nanotubes (CNTs, 0~1.0 weight percent (wt%)). Borate-crosslinked STG matrices were synthesized using hydroxyl-terminated polydimethylsiloxane and boric acid. Rheological analysis demonstrates that a CNT loading of 0.25 wt% maximizes enhancement of the storage modulus, achieving values of 124.5 kPa at 0.1 Hz (exceeding the pure STG by 463%) and 284.2 kPa at 100 Hz, while preserving viscoelastic balance. The compressive modulus (100 mm/min) increased by approximately 180% via CNT-enabled load transfer (from 93 kPa to 259 kPa), while tensile stress surged 21.8-fold to 82.7 kPa at 100 mm/min. Impact tests show 0.25% CNT-STG reduces peak force by 80.1% (3,331 N versus 16,750 N) and extends dissipation duration by 206.5%. Helmet simulations under industrial impact standards confirm 27.7% peak force reduction (from 4,663 N to 3,373 N) with 26.2% longer impact duration, demonstrating synergistic energy redistribution via CNT networks. Optimal dispersion enables hierarchical dissipation through interfacial slippage, dislocation motion, and elastic storage, avoiding agglomeration at high loadings. This establishes a nanoscale design paradigm for high-performance STG composites with rapid thickening, structural stability, and superior impact protection.