Influence of Drawing and Temperature on the Optical and Structural Properties of Monofilament PP Sutures

Abstract

Abstract The influence of drawing and temperature on the optical and structural properties of monofilament polypropylene sutures (PP) were investigated using interferometry. Two techniques have been used in this study: 1) the polarizing interference microscope, 2) multiple-beam Fizeau interferometry. The polarizing interference microscope is used to study the variation of refractive indices and birefringence of PP sutures at different draw ratios and stresses. The stress-strain diagram of PP sutures was studied. The resulting data was used to calculate the average work per chain, Poisson's ratio, strain optical coefficient, Young's modulus and optical orientation function. Multiple-beam Fizeau interferometry was used to study the temperature effect on optical properties of PP sutures with temperature ranging from 19 to 40°C. Relationships between the optical parameters at different temperatures are given. Calculation of the density, crystallinity, dielectric constant and dielectric susceptibility at different temperatures are done. The results obtained, clarify the effect of drawing and temperature on the structure of PP sutures. Microinterferograms are given for illustration.