Preparation And Research On Polyester Based Orthodontic Composite Material

Invisible orthodontic oral correction materials are clinically used in the field of orthodontics.Their appearance is not only more acceptable to users than traditional orthodontics,but also has strong comfort and safety,so the market is huge.However,due to the fact that related materials are imported from abroad,their costs are extremely high and it is difficult to achieve technology popularization in the short term.The matrix material selected in this study is thermoplastic polyester PETG The new orthodontic orthodontic materials are developed based on the study of blending to change the awkward situation of orthodontic materials relying on import.The modifiers selected in this topic are TPU and PC,which are systematically studied to affect the performance of PETG The following conclusions are drawn:(1)When the proportion of TPU in the PETG/TPU mixture is within 15%,the resulting binary PETG/TPU mixture is highly transparent and has a light transmission rate of more than 86%;The data shows that when the TPU accounts for 15%,the tensile strength of the blending system reaches 37 MPa,which has been greatly reduced and can not achieve the demand for the required corrective power of the product;(2)In PETG/PC blends,the ratio does not significantly affect the transparency of the blends,but the tensile strength,stiffness,viscosity,and melting index of the blends are all positively related to the content of the PC.The stress relaxation rate and water absorption rate are negatively related to it.Experimental data show that when the PETG/PC was matched by 60/40,the resulting blends were highly transparent,with a light permeability of up to 92%,a tensile strength of 55 MPa,a stress relaxation rate of 0.0409 N/s,and a water absorption rate of 0.40%.The hardness is 84.6D,which is close to the performance of the imported material;(3)In the PETG/PC/TPU ternary blending system,60/40 is used as the fixed ratio of PETG/PC.Experiments have shown that when 10%TPU is added,the mixing system is highly transparent,the light permeability exceeds 85%,and the tensile strength is 58 MPa.The stress relaxation rate is 0.0354 N/s,and the water intake is 0.43%.The performance is no less than that of imported materials,and it is even better than imported materials in some performance indicators.