Preparation And Research On Polyester Based Orthodontic Composite Material

Transparent and invisible orthodontic material with its beautiful,comfortable, health, security and other advantages have been widely used,now the used invisible orthodontic dental materials all rely on imports,the high price limits the promotion of this technology and its application.We use the thermoplastic polyester PETG as matrix material, which weremodified by blending research, excellent comprehensive properties oforthodontic materials were preparated, we explored the possibility ofsubstituting the import orthodontic materials.TPU, PBT, PC and other materials have been used as matrixmodifier, the influences of different dosage on the properties of PETGmaterials have been disscused:(1) PETG/TPU blends have been prepared, when the TPU contentbelow15%the system has good transparency, the light transmission rateis above85%, when the content is15%, the tensile strength of thematerial is37.6MPa, which can not provide the enough strongorthodontic force.(2) PETG/PBT blends have been prepared,when the PBT content below25%, the system has good transparency,the light transmission rateis above89%, the saturated water absorption of the system is0.39%, therelaxation rate is0.032N/s,tensile strength is50Mpa.(3) PETG/PC blends have been prepared, the addition of PC did notaffect the transparent performance of the system,with the increasing ofPC,the tensile strength and rigidity increased, while the relaxation rateand the water absorption decreased, but the viscosity increased, the meltindex became large, which made the processing more difficult. When theratio of PETG/PC was60/40, the transmission rate of the system reached91%, the tensile strength was56MPa, the relaxation rate was0.0413N/s,and the absorbent capacity was0.41%, which had good comprehensiveperformance.(4) PETG/PC/TPU blends have been prepared, we added differentcontent TPU.with the ratio of PETG/PC being60/40, when when the TPUcontent was10%, the transmission rate was86%, the tensile strength was58MPa, the rate of relaxation was0.0345N/s, the absorbent capacity was0.43%and target material close to or even superior to the standardmaterial.