Influences of Substrate Adhesion and Particle Size on the Shape Memory Effect of Polystyrene Particles
Influences of Substrate Adhesion and Particle Size on the Shape Memory Effect of Polystyrene Particles
复制标题
DOI：
10.1021/acs.langmuir.6b00588
复制
发表时间：
2016-04-19
期刊：
影响因子：
3.9
通讯作者：
Ding, Yifu
中科院分区：
文献类型：
--
作者：
Cox, Lewis M.;Killgore, Jason P.;Ding, Yifu
近年来，微米级和纳米级聚合物颗粒的配方和应用迅速激增，但对其机械行为的了解却没有相应增长。在这项研究中，我们研究了压缩应变、基材表面能和颗粒尺寸影响聚苯乙烯颗粒形状记忆周期的方式。使用纳米压印光刻技术，不同尺寸的颗粒被编程为与不同表面能的基底接触的高度变形的临时形状。原子力显微镜用于获得颗粒形状恢复动力学的原位测量，扫描电子显微镜用于评估形状记忆循环结束时颗粒轮廓的差异。最后，有限元模型用于研究表面能在较小长度尺度上日益增长的影响。结果表明，基材粘附对颗粒回收的影响取决于尺寸，并且在亚微米长度尺度上可能占主导地位。
Formulations and applications of micro- and nanoscale polymer particles have proliferated rapidly in recent years, yet knowledge of their mechanical behavior has not grown accordingly. In this study, we examine the ways that compressive strain, substrate surface energy, and particle size influence the shape memory cycle of polystyrene particles. Using nanoimprint lithography, differently sized particles are programmed into highly deformed, temporary shapes in contact with substrates of differing surface energies. Atomic force microscopy is used to obtain in situ measurements of particle shape recovery kinetics, and scanning electron microscopy is employed to assess differences in the profiles of particles at the conclusion of the shape memory cycle. Finally, finite element models are used to investigate the growing impact of surface energies at smaller length scales. Results reveal that the influence of substrate adhesion on particle recovery is size-dependent and can become dominating at submicron length scales.