| Popis: |
A piezoelectric, thin film polyvinylidene fluoride (PVDF) material was developed for application as a blood pressure/flow sensor within an artificial heart. In an effort to increase the piezoelectric coefficient, d31, and maximize the sensitivity of the PVDF material, nanoscale pores were introduced into the thin films. The purpose of the pores was to increase the mechanical strain of the material under compressive loading, and thus increase the charge separation and piezoelectric coefficient. Strain tracking under tensile loading was performed to determine the elastic modulus and Poisson’s ratio of the PVDF material, which were then used to model a simulated material in COMSOL Multiphysics software. Simulations were run to determine the d31 piezoelectric coefficient of the material, and the simulated results were compared with experimental results from a previous study. As porosity of the PVDF films increased, the experimental results showed an increase in d31 from 21.3 pC/N to 51.3 pC/N, or 141%. The simulated results showed an increase in d31 from 16.7 pC/N to 47.2 pC/N, or 183%. The similarity between previous experimental results and novel simulated results suggests that the simulated model used is a reliable method for estimating d31 of PVDF. |
