利用形状记忆效应将微观物体从低纵横比转换为高纵横比。

Switching microobjects from low to high aspect ratios using a shape-memory effect.

作者信息

Friess Fabian, Lendlein Andreas, Wischke Christian

机构信息

Institute of Active Polymers and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Hereon, Kantstr. 55, 14513 Teltow, Germany.

Institute of Chemistry, University of Potsdam, Karl-Liebknecht-Str. 25, 14476 Potsdam, Germany.

出版信息

Soft Matter. 2021 Oct 27;17(41):9326-9331. doi: 10.1039/d1sm00947h.

DOI:10.1039/d1sm00947h

PMID:34605513

Abstract

Spherical particles from shape-memory polymers (SMP) can be stretched to ellipsoids with high aspect ratio (AR) and temporarily stabilized. They can switch back to low AR upon thermal stimulation. Here, the creation of an alternative shape-switching capability of particles from low to high AR is introduced, where a SMP matrix from polyvinyl alcohol (PVA) is used to create crosslinked high AR particles and to program the embedded micrometer-sized particles from a second SMP (oligo(ε-caprolactone) micronetworks, MN) with a low switching temperature . This programming proceeds through shape-recovery of the PVA matrix, from which the MN are harvested by PVA matrix dissolution. The use of a dissolvable SMP matrix may be a general strategy to efficiently create systems with complex moving capabilities.

摘要

形状记忆聚合物（SMP）制成的球形颗粒可以被拉伸成具有高纵横比（AR）的椭球体并暂时稳定下来。在热刺激下，它们可以恢复到低纵横比。在此，引入了一种使颗粒从低纵横比切换到高纵横比的替代形状切换能力，其中使用聚乙烯醇（PVA）制成的SMP基质来创建交联的高纵横比颗粒，并对来自第二种SMP（低聚（ε-己内酯）微网络，MN）的嵌入微米级颗粒进行编程，该微网络具有较低的转变温度。这种编程过程通过PVA基质的形状恢复来进行，通过溶解PVA基质从中获取MN。使用可溶解的SMP基质可能是有效创建具有复杂移动能力系统的通用策略。