| UV-curing 3D printing technology, widely applied in aerospace, industry, medical and other fields, possesses the advantages of short manufacturing cycle, high forming precision and customization design. The development and application of 3D printing technology are determined by the type and property of the printing materials. However, the technology of 3D printing materials(building materials and supporting materials) is mastered by only a few American and Israel companies. In particular, the development of 3D printing technology in China is severely hindered due to the lack of the supporting materials. In this paper, the temperature sensitive supporting material with low visocity and low surface tension and the reactive-type supporting material with high mechanical properties and water solubility were prepared, respectively. The properties of the two supporting materials before and after curing were studied.Based on the thermosensitive and gel properties of P123, the temperature sensitive supporting material was prepared with temperature sensitive polymer P123, UV-curable monomer PEG400 DA and PEG1000 DA, water soluble photoinitiator 907, levelling agent BYK331 and other agents. Then, the curing mechanism of the prepared supporting material was studied. Finally, the optimum formula of the prepared temperature sensitive supporting material was obtained, the comprehensive properties of which at 25? were: the viscosity, the surface tension, the curing shrinkage rate and the solubility were 34.2 mPa·s, 33.463mN/m, 0.97% and 26.77%, respectively.Polyethylene glycol monoacrylate(PEGmA) with excellent mechanical properties and water solubility was synthesized by esterification of polyethylene glycol 400(PEG-400) and acrylic acid(AA) with p-toluenesulfonic acid as catalyst, hydroquinone as inhibitor and toluene as water carrying agent. Then, the synthesized products were characterized by FTIR, 1H NMR and HPLC. Finally, the optimum synthetic conditions of PEGmA were obtained: the molar ratio of AA to PEG-400 was 1.5:1, the weight fractions of p-toluenesulfonic acid and hydroquinone were 1.5wt% and 1wt%, respectively(according to the weight of PEG-400 and AA), the esterification temperature was 120°C and the esterification time was 6h. The ester yield reached 85.7% under the optimum conditions.Based on the UV-curing ability of PEGmA and the good mechanical properties and water solubility of the cured product of PEGmA, the reactive-type supporting material was prepared with the synthesized PEGmA, photoinitiator 369 and ITX, leveling agent BYK331 and other agents. Then, the curing mechanism and the water solubility of the prepared supporting material were studied. Finally, the optimum formula of the prepared reactive-type supporting material were obtained, the comprehensive properties of which at 25? were: the viscosity, the surface tension, the tensile strength, the hardness and the solubility were were 68.7 mPa·s, 36.571mN/m, 24.21 MPa, 42 HA and 50.32%, respectively. |
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