Fecha de publicación: -- Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE A castor oil-based photocurable resin is formulated for LCD 3D printing. It exhibits exceptional flexibility with 160% elongation at break. Loaded with IR3535, the printed composite shows temperature-controlled release, four times faster at 30°C than at 20°C over 28 days. This bio-based material combines printability, flexibility, and drug delivery for wearable and medical devices.


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.