Mayer Florian, Laa Dominik, Koch Thomas, Stampfl Jürgen, Liska Robert, Ehrmann Katharina
Institute of Applied Synthetic Chemistry, Technische Universität Wien, Vienna, Austria.
Institute of Materials Science and Technology, Technische Universität Wien, Vienna, Austria.
Mater Horiz. 2025 Mar 4;12(5):1494-1503. doi: 10.1039/d4mh01261e.
Additive manufacturing technologies and, in particular, vat photopolymerization promise complex structures that can be made in a fast and easy fashion for highly individualized products. While the technology has upheld this promise many times already, some polymers are still out of reach or at least problematic to print reliably. High-performance epoxide-based resins, which are regulated by chain transfer multifunctional alcohols, are a typical example of resins with late gel points, which require long irradiation times and high light intensities to print. Therefore, we have developed a dual-colour printing approach where rapid radical curing of a soft, wide-meshed polymer network facilitates fast and easy 3D structuring of the subsequently slow curing step-growth formulation at an orthogonal initiation-wavelength regime. Thereby the methacrylate system acts as a scaffold for an uncured epoxide alcohol system during the printing process, which is then cured with UV light post-printing. This way tough alcohol-regulated epoxy-systems become accessible to vat photopolymerization achieving outstanding high-resolution 3D printed parts without significant layering effects. The demonstrated wide-meshed matrix-assisted printing approach has the potential to make a multitude of slowly curing resins accessible to vat photopolymerization techniques, at low irradiation intensities and high curing speeds.
增材制造技术，尤其是光固化3D打印技术，有望以快速简便的方式制造出适用于高度个性化产品的复杂结构。虽然该技术已经多次兑现了这一承诺，但某些聚合物仍然难以实现可靠打印，或者至少存在问题。由链转移多功能醇调节的高性能环氧化合物基树脂是具有较晚凝胶点的树脂的典型例子，这类树脂需要较长的辐照时间和较高的光强度才能打印。因此，我们开发了一种双色打印方法，在这种方法中，柔软、宽网孔聚合物网络的快速自由基固化有助于在正交引发波长范围内对随后缓慢固化的逐步增长配方进行快速简便的3D结构化。从而，在打印过程中，甲基丙烯酸酯体系充当未固化环氧化合物醇体系的支架，然后在打印后用紫外线固化。通过这种方式，坚韧的醇调节环氧体系可以通过光固化3D打印技术实现，从而获得出色的高分辨率3D打印部件，且没有明显的分层效应。所展示的宽网孔基质辅助打印方法有可能使多种缓慢固化的树脂能够通过光固化3D打印技术实现，且辐照强度低、固化速度快。
