Measurement and calculation of the parameters of mechanical properties of silicone rubber

Abstract

The measurement and calculation of the mechanical properties of silicone rubber used for the manufacture of a prosthesis for the auricle of patients based on dental CAD/CAM systems, using a hybrid technology that includes traditional and digital methods of manufacturing medical devices were performed. Mechanical tensile tests were carried out in a climatic chamber at various temperatures: -20; 0; 25; 40 °C. All mechanical characteristics of silicone rubber lay in a very limited range of values and monotonically decreased with increasing test temperature from -20 to + 45°C. At the same time, the elastic characteristics (elastic modulus) decreased by 1.55, deformation (fracture deformation) - by 1.98, strength (tensile strength) - by 2.37 times. The average values of tensile strength were 6.54 MPa, fracture deformation - 1480.61%, modulus of elasticity - 0.53 MPa, and temperature gradient: 0.08 MPa/deg, 14.8%/deg and 0.004 MPa/deg, respectively. In the framework of the Mooney - Rivlin hyperelastic model, the coefficients of the model C 01 and C 10 are determined, which can be used as parameters when performing simulation modeling of the stress-strain state of prostheses. Based on the data obtained, an assessment was made of the cross-linked density of the silicone rubber material as a synthetic polymer. It turned out to be equal to 0.49.