Klikovits Nicolas, Sinawehl Lisa, Knaack Patrick, Koch Thomas, Stampfl Jürgen, Gorsche Christian, Liska Robert
Cubicure GmbH, 1230 Vienna, Austria.
ACS Macro Lett. 2020 Apr 21;9(4):546-551. doi: 10.1021/acsmacrolett.0c00055. Epub 2020 Mar 25.
The cationic ring-opening polymerization (CROP) of 2-oxazolines gives polymers with unique characteristics arising from its polyamide backbones and structural versatility. Up to now, poly(2-oxazoline)s were obtained by classical thermal polymerization methods not aiming for application in bulk curing of structural polymers. We introduce the cationic photopolymerization of 2-oxazolines at elevated temperatures for the direct UV-induced curing of materials with exclusive chemical and structural particularities. After efficient photoinitiation via onium salt photoacid generators (PAGs), the immanent low-rate propagation is crucially promoted by thermal energy input to the ring-opening reaction. In simultaneous thermal analysis (STA), photo-DSC, and (thermo)mechanical analyses we investigated the UV-induced CROP of 2-oxazolines in a temperature range of 100-140 °C and show the exceptional potential of the introduced photopolymers. Furthermore, we applied the photopolymerizable system in Hot Lithography, a stereolithography-based 3D printing technology at elevated temperatures.
2-恶唑啉的阳离子开环聚合（CROP）可得到具有独特特性的聚合物，这些特性源于其聚酰胺主链和结构的多样性。到目前为止，聚（2-恶唑啉）是通过传统的热聚合方法获得的，并非旨在用于结构聚合物的本体固化。我们介绍了在高温下2-恶唑啉的阳离子光聚合，用于具有独特化学和结构特性的材料的直接紫外线诱导固化。通过鎓盐光酸产生剂（PAG）进行有效光引发后，通过向开环反应输入热能，可显著促进内在的低速率链增长。在同步热分析（STA）、光差示扫描量热法（photo-DSC）和（热）机械分析中，我们研究了在100-140°C温度范围内2-恶唑啉的紫外线诱导CROP，并展示了所引入的光聚合物的卓越潜力。此外，我们将可光聚合体系应用于热光刻技术，这是一种基于立体光刻的高温3D打印技术。
