Romeis Manuel, Drummer Dietmar
Institute of Polymer Technology (LKT), Friedrich-Alexander-University Erlangen-Nuremberg, Am Weichselgarten 9, 91058 Erlangen, Germany.
Polymers (Basel). 2021 Sep 17;13(18):3139. doi: 10.3390/polym13183139.
In this research, an epoxy-based dual-cure system is developed and characterized for SLA additive manufacturing. Dual-cure systems consist of UV-curable acrylates and thermal active components. The second curing step offers an additional degree of freedom to design specific material properties. In this study, a blend of varying concentrations of an epoxy/curing agent mix, respectively, DGEBA, DICY and photocurable methacrylate, was used to create a material that is printable in the SLA process into a UV-cured or green part and subsequently thermally cured to achieve superior thermal and mechanical properties. Calorimetric measurements were performed to determine the reactivity of the thermal reaction at different concentrations of epoxy. The fully cured specimens were tested in mechanical and dynamic mechanical measurements, and the results showed a significant improvement in tensile stress and glass transition temperature with rising epoxy concentrations. Fractured surfaces from tensile testing were investigated to further characterize the failure of tested samples, and thermal degradation was determined in TGA measurements, which showed no significant changes with an increasing epoxy concentration.
在本研究中，开发并表征了一种用于立体光刻（SLA）增材制造的环氧基双固化体系。双固化体系由可紫外光固化的丙烯酸酯和热活性成分组成。第二步固化为设计特定材料性能提供了额外的自由度。在本研究中，分别使用不同浓度的环氧/固化剂混合物（双酚A二缩水甘油醚（DGEBA）、双氰胺（DICY））和可光固化的甲基丙烯酸酯的共混物，来制备一种在SLA工艺中可打印成紫外光固化或绿色部件的材料，随后进行热固化以获得优异的热性能和机械性能。进行量热测量以确定不同环氧浓度下热反应的反应活性。对完全固化的试样进行力学和动态力学测试，结果表明，随着环氧浓度的增加，拉伸应力和玻璃化转变温度有显著提高。对拉伸试验后的断裂表面进行了研究，以进一步表征测试样品的失效情况，并通过热重分析（TGA）测量确定热降解情况，结果表明随着环氧浓度的增加没有显著变化。
