Abstract Melt electrowriting (MEW) is mostly applied to print complex three-dimensional (3D) structures using traditional, relatively hydrophobic polymers, such as polycaprolactone. Here, we 3D printed a supramolecular hydrophilic polymer into a solid micrometer-sized fiber structure, solely held together via non-covalent interactions. Interestingly, the solid fibers showed anisotropic swelling in a humid environment as demonstrated by the longitudinal and transverse surface strain determined using a novel global digital height correlation algorithm. This anisotropy in swelling is proposed to originate from a shear-induced orientation of crystals packed into lamellae as shown with small-angle x-ray scattering measurements. The MEW fibers were dried after swelling to study structural differences. Remarkably, no differences in nano-structural conformation in the micrometer-sized fibers was observed after swelling and subsequent drying. In conclusion, a free-standing supramolecular polymer-based hydrogel scaffold, displaying anisotropic hygro-expansion, is shown to be produced using MEW. This unique combination of 3D printing, via a top-down approach, and supramolecular polymer chemistry, via a bottom-up approach, provides new ways to introduce anisotropy and hierarchy in aqueous supramolecular systems. This will open the door towards even more complex hierarchical structures with unprecedented properties.

中文翻译：

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由于结合了 3D 电写和超分子聚合物组装，水凝胶纤维中的各向异性湿膨胀

摘要 熔体电写 (MEW) 主要用于使用传统的、相对疏水的聚合物（如聚己内酯）打印复杂的三维 (3D) 结构。在这里，我们将超分子亲水聚合物 3D 打印到实心微米级纤维结构中，通过非共价相互作用单独保持在一起。有趣的是，固体纤维在潮湿环境中表现出各向异性膨胀，正如使用新型全局数字高度相关算法确定的纵向和横向表面应变所证明的那样。这种溶胀的各向异性被认为源于填充到薄片中的晶体的剪切诱导取向，如小角度 X 射线散射测量所示。MEW 纤维在溶胀后干燥以研究结构差异。值得注意的是，在溶胀和随后的干燥后，未观察到微米级纤维的纳米结构构象存在差异。总之，显示出各向异性湿膨胀的独立式超分子聚合物基水凝胶支架是使用 MEW 生产的。这种通过自顶向下方法的 3D 打印和通过自底向上方法的超分子聚合物化学的独特组合，提供了在水性超分子系统中引入各向异性和层次结构的新方法。这将为具有前所未有的特性的更复杂的层次结构打开大门。这种通过自顶向下方法的 3D 打印和通过自底向上方法的超分子聚合物化学的独特组合，提供了在水性超分子系统中引入各向异性和层次结构的新方法。这将为具有前所未有的特性的更复杂的层次结构打开大门。这种通过自顶向下方法的 3D 打印和通过自底向上方法的超分子聚合物化学的独特组合，提供了在水性超分子系统中引入各向异性和层次结构的新方法。这将为具有前所未有的特性的更复杂的层次结构打开大门。