The effect of different thermal treatment on the physical properties of PGA/PCL copolymer suture material.

Samples of polyglycolic acid PGA/polycaprolactone PCL copolymer absorbable suture materials, which is called Poliglecaprone PGC copolymer suture, were thermally treated by two different processes. The first method is the direct heat exposure, from 20 to 38 °C, in the surrounding medium. Which is an environmental study. The other method is the annealing process at temperatures ranged from 65, 80, 100, 120, and 140 °C, for two different duration periods 60 and 120 min. This is an extensive technical study. The refractive indices of thermally treated PGA/PCL copolymer sutures were measured using multiple-beam Fizeau fringes. The birefringence profiles across the suture cross-sections were studied for different annealing conditions. The effect of heat on the polarizabilty per unit volume, dielectric properties, and suture diameter were investigated. The activation energy for the heating processes was calculated using Arrhenius equation. Microinterferograms are given for illustration.