Analysis of mechanical characteristics by birefringence microscope

摘要

The mechanical characteristics of polymer materials are of interest to the chemical industry. There are requirements for observation of changes of internal structure to stress. A number of samples under various stress conditions have provided interesting information upon analysis by microscopic birefringence measurement. In the present paper, we propose a birefringence measurement method for observation of the internal structure of polymer materials and analysis of the relationship between a given stress and the corresponding birefringence distribution. The proposed measurement system consists of a He-Ne laser, polarizers, a half-wave plate and a quarter-wave plate. The birefringence distributions of gelatin, such as the phase difference and azimuthal angle, are shown for the case of applied uniaxial and biaxial stress.