Highly Flexible and Photo-Activating Acryl-Polyurethane for 3D Steric Architectures

• Published in: Polymers Vol. 13; no. 6; p. 844
• Main Authors: Bae, Ji-Hong, Won, Jong Chan, Lim, Won Bin, Lee, Ju Hong, Min, Jin Gyu, Kim, Si Woo, Kim, Ji-Hyo, Huh, PilHo
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI 10-03-2021
• Subjects: photopolymer; digital light processing; three-dimensional printing architectures; photocurable resin; acryl-polyurethane
• ISSN: 2073-4360; 2073-4360
• DOI: 10.3390/polym13060844

An acryl-functionalized polyurethane (PU) series was successfully synthesized using poly(tetramethylene ether) glycol-methylene diphenyl diisocyanate (PTMG-MDI) oligomer based on urethane methacrylates to control the flexibility of photo-cured 3D printing architectures. The mass ratio of acryl-urethane prepolymer: 1,4-butanediol (BD) chain-extender: diphenyl(2,4,6-trimethylbenzoyl) phosphine oxide (TPO) photoinitiator was 10:0.25:1. To produce suitably hard and precisely curved 3D architectures, the optimal UV absorbance and exposure energy of the acryl-PTMG-MDI resin were controlled precisely. Owing to the optimized viscosity of the acryl-PTMG-MDI resins, they could be printed readily by digital light processing (DLP) to form precisely curved 3D architectures after mixing with 1,6-hexanediol diacrylate (HDDA). The acryl-PTMG-MDI formulations showed much better flexural resolution than the neat resins. The printed 3D structure exhibited high surface hardness, good mechanical strength, and high elasticity for flexible applications in consumer/industrial and biomedical fields.