Shock wave energy dissipation in strong and tough poly(dimethylsiloxane) composites with controlled microstructure

Abstract

Of particular significance is to design materials mitigating shock waves induced by blast and high-speed impact for protecting people and structures. Polymer composites possess remarkable energy-dissipation performance, but there is a lack of awareness about precise regulation of energy dissipation through control over material microstructure. Herein, strong and tough poly(dimethylsiloxane) (PDMS) composites with particle-mediated microstructure were devised for shock wave energy dissipation. Morphological observation revealed that composites with agglomerate structure and homodisperse structure were obtained by adjusting particle surface chemistry. Compared with pure PDMS, strength and toughness for composites with agglomerate structure increased by 65 % and 280 %, respectively, while these characteristics for composites with homodisperse structure rised by 90 % and 433 %, respectively. During laser-induced shock compression, composites with homodisperse structure exhibited better energy dissipation ability than composites with agglomerate structure. In comparison with pure PDMS, the shock wave peak pressure for composites with agglomerate structure and homodisperse structure reduced by up to 43 % and 75 %, respectively. As for composites with agglomerate structure, the mechanism for shock wave energy dissipation derived from fast segmental dynamics and low glass transition temperature of PDMS matrix, agglomerate breakup and wave scattering at agglomerate/matrix interfaces. The raised energy dissipation effect for composites with homodisperse structure rooted in enhanced reflections of shock waves at increased particle/matrix interfaces. These findings provide a promising strategy to construct energy-adsorbing materials with controlled microstructure for personnel and equipment protection.