Castor oil‐based UV‐curable polyurethane acrylate resins for digital light processing (DLP) 3D printing technology

Abstract

In this work, a novel UV‐curable polyurethane acrylate (PUA) oligomer was developed from castor oil (CO). Reaction monitoring and structures of the PUA oligomer were characterized by Fourier transform infrared (FTIR) and 1H nuclear magnetic resonance (NMR). Subsequently, a series of UV‐curable resins were prepared by combining PUA with different reactive diluents, and their effect on thermal and mechanical properties was investigated. From the overall characterization trend, it was observed that the formulation containing trimethylolpropane triacrylate (TMPTA) showed the highest mechanical strength and thermal stability. Whereas the formulation containing isobornyl acrylate (IBOA) showed the least performance, and dipropyleneglycol diacrylate (DPGDA) showed properties ranging between TMPTA and IBOA. Furthermore, incorporating 1% TiO2 into the formulation increases the resin's viscosity and mechanical properties without disturbing its thermal stability. This work offered a simple method to prepare vegetable oil‐based high‐performance PUA resins that could be used in the 3D printing industry for general‐purpose prototyping applications to make architectural models, automotive components, and medical components.

Synthesis and application of sustainable vegetable oil-based polymers in 3D printing

“…The global research community is actively investigating numerous oils in this context. To date, soybean oil, 11 castor oil, 46 and various combinations of rapeseed, linseed, and grapeseed oils 47 are the plant oils that have been successfully 3D printed, leading to the development of products suitable for diverse applications. This advancement has the potential to serve as a significant milestone in the pursuit of a sustainable world.…”

Renewable Photopolymers: Transformation of Biomass Resources into Value-Added Products Under Light

“…With its innate hydroxyl groups, castor oil can be modified by reaction with diisocyanate, such as isophorone diisocyanate, prior to the treatment with hydroxyl or amino terminated (meth)­acrylate monomers (Scheme ). For example, the end-cap of the isocyanate with HEMA led to the formation of UV curable resins which can be 3D printed with reactive diluents (Scheme A) . In another research, 2-( tert -butylamino)­ethyl methyacrylate (TBEM) was used to form steric urea bonds with castor oil and diisocynate to give a polyurethane monomer COIT (Scheme B) .…”

“…For example, the endcap of the isocyanate with HEMA led to the formation of UV curable resins which can be 3D printed with reactive diluents (Scheme 6A). 85 In another research, 2-(tert-butylamino)ethyl methyacrylate (TBEM) was used to form steric urea bonds with castor oil and diisocynate to give a polyurethane monomer COIT (Scheme 6B). 34 The steric uera bonds in COIT can undergo dynamic dissociation and allow the printed objects to be reversed into liquid resins at elevated temperature with additional COIT.…”