Vega Daniel A, Lance Pedro, Zorzi Enzo, Register Richard A, Gómez Leopoldo R
Department of Physics, Universidad Nacional del Sur-IFISUR-CONICET, 8000 Bahía Blanca, Argentina.
Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey, 08544, USA.
Soft Matter. 2023 Aug 16;19(32):6131-6139. doi: 10.1039/d3sm00765k.
We employ molecular dynamics simulations to investigate the shock compression of linear semiflexible polymers. While the propagation velocity of a shock primarily depends on density, both chain rigidity and chain orientation significantly influence the shock width and the final temperature of the system. In general, the shock wave triggers molecular buckling in chains oriented perpendicular to the compression front. Following the passage of the front, the semiflexible chains buckle with a wavelength that decreases with the compression speed as ∼ , and subsequent relaxation leads to a banana-like liquid crystal phase. In ordered systems with molecules oriented perpendicular to the compression front, the shock width increases by a factor of up to 10 compared to a similar isotropic system, resulting in enhanced shock energy absorption. These findings indicate that chain stiffness plays a critical role in the impact absorption properties of polymeric materials.
我们采用分子动力学模拟来研究线性半柔性聚合物的冲击压缩。虽然冲击波的传播速度主要取决于密度，但链的刚性和链的取向都会显著影响冲击宽度和系统的最终温度。一般来说，冲击波会引发垂直于压缩前沿取向的链中的分子屈曲。在前沿通过后，半柔性链会以一个随压缩速度按 ∼ 减小的波长发生屈曲，随后的弛豫会导致形成类似香蕉状的液晶相。在分子垂直于压缩前沿取向的有序系统中，与类似的各向同性系统相比，冲击宽度增加高达10倍，从而增强了冲击能量吸收。这些发现表明链的刚度在聚合物材料的冲击吸收性能中起着关键作用。
