【摘要】 通过将钕铁硼(NdFeB)颗粒分散到剪切增稠胶(S-ST)中,研发出具有优异的预磁化增强(Pre-Magnetized Enhanced,PME)和剪切增稠效应的双重刺激响应剪切增稠复合材料(Dual-Stimuli-Responsive Shear Stiffening Polymer Composite,DSR-SST).当外界剪切频率从0.1 Hz增加到100 Hz时,DSR-SST的储能模量(G′)从10~2Pa增加到106Pa,显示明显的剪切增稠效应.同时,该多功能DSR-SST材料的力学性能也可通过剪切频率和外界磁场进行调控.更重要的是,具有高剩磁特性的DSR-SST表现出优异的PME效应,材料在经1200 mT磁场短暂预磁化处理后,其G′可从1.64 MPa定向增大到2.34 MPa.DSR-SST还表现出理想的循环稳定性能.研究结果表明,NdFeB颗粒的高剩磁性以及颗粒链的形成是导致该多功能材料特殊力学性能的主要原因,DSR-SST材料具有良好的循环稳定性、可塑性和黏弹性,因而在人体防护和阻尼减震等领域具有重要的应用前景.更多还原

【Abstract】 A kind of innovative dual-stimuli-responsive shear stiffening polymer composite(DSR-SST) with excellent premagnetized enhanced(PME) effect and ideal adhesion properties was developed by dispersing NdFeB particles into shear stiffening(S-ST) polymer matrix. Owing to its S-ST characteristic, the storage modulus(G′) of DSR-SST can increase from 10~2 Pa to 106 Pa when the shear frequency of applied stress varies from 0.1 to 100 Hz. Meanwhile, the stiffness of the multi-functional DSR-SST can also be precisely tunable by shear frequency and magnetic field. More importantly, DSR-SST with high remanence exhibits excellent PME effect in which the G′ can be directionally increased from 1.64 MPa to 2.34 MPa through 1200 mT of pre-magnetization process in short time. Additionally, the mechanism of high residual magnetization and the movement of NdFeB particle chains are proposed and discussed. Finally, the ideal cyclic stability, plastic and adhesive characteristics guarantee the composite with reliable mechanical performance and longer lifespan in safeguarding and damping.更多还原