Castor Oil‐Based Flexible Composite Resin With Drug Delivery Capabilities Based on
LCD
Light‐Curing
3D
Printing Technology
Jintao Hu, Hongyue Hao, Huilin Liu, Lizhen Wu, Zhigang Guo, Jiazhou He, Jinhuang Wu, Wanying Lu, Wenxu Zheng, Wuyi Zhou ABSTRACT
Petroleum‐based photopolymerizable resins face challenges in meeting green manufacturing demands due to environmental unsustainability and biotoxicity issues. This study synthesized a castor oil‐based polyurethane resin with excellent mechanical properties and temperature‐responsive characteristics using an LCD photopolymerization 3D printing process. The resin was synthesized from castor oil, hexamethylene diisocyanate (HDI), and 2‐hydroxyethyl methacrylate (2‐HEMA). Experimental results demonstrate that the composite resin containing 20% isobornyl acrylate (IBOA) exhibits outstanding processability and flexibility, achieving a tensile elongation at break of 160% and a thermal decomposition range of 300°C–465°C. The drug‐loaded system (containing 10% IR3535, ethyl butylacetylaminopropionate, trade name: Immerning) exhibited controlled release behavior upon thermal stimulation. At 30°C, the drug release rate increased fourfold compared to 20°C, with a sustained release period exceeding 28 days. Consequently, the developed 3D‐printable castor oil‐based resin holds significant application value in fields such as flexible electronic packaging and smart medical devices.