机械拉伸

Modulating molecular and nanoparticle transport in flexible polydimethylsiloxane membranes

ty10086 提交于 周四, 08/26/2021 - 13:38
Abstract(#br)The ability to fabricate flexible filtration membranes that can selectively separate particles of different sizes is of considerable interest. In this article, we describe a facile, reproducible and simple one-step method to produce pores in polydimethylsiloxane (PDMS) membranes. We embedded micron-sized NaHCO 3 particles in 50\u003cce:hsp sp=\"0.25\"/\u003eμm thick PDMS films. After curing, the membranes were immersed in concentrated HCl acid. Pores were generated in the membrane by the evolution of CO 2 gas from the reaction of NaHCO 3 and HCl.

Ridged Zn/PDMS smart surface with wide-range reversible wettability and high sensitivity responsive to mechanical strain

ty10086 提交于 周四, 08/26/2021 - 12:45
具有动态可调节润湿性的智能表面在微流体、生物医学工程和柔性电子领域有着重要的作用。机械应变是一种很有前途的调节表面润湿性的刺激,然而,要同时实现宽范围可逆润湿性和高灵敏度仍然是一个很大的挑战。本研究通过在预拉伸的聚二甲基硅氧烷( PDMS )上溅射沉积锌( Zn )纳米薄膜,在薄膜-基底体系的基础上,裁剪出峰处有裂纹的高度有序的准周期脊状图案。通过调节施加的应变,脊状Zn / PDMS表面的接触角( CA )在115° ~ 143°之间有很好的可调谐性。值得注意的是,这种结构在仅28.6 %的外加应变下具有较宽的CA变化范围( ~ 28° ),表明具有较高的响应灵敏度( η   =   98° )。这一结果归因于宽宽宽比为0.07 ~ 0.54和高变化率( ~ 1.70 )的裂纹脊。而且,脊状Zn / PDMS表面的响应可逆性在没有特殊保护的情况下保持高达1000 个循环和60 天。优异的性能使得脊状表面可以成为各种技术应用中很有前景的构件,特别是在小应变要求的场合。