Polyesters from renewable sources

Aliphatic polyesters are one of the classes of materials that can potentially meet the varying requirements put for tissue scaffolds. In recent years, much attention was paid to design biocompatible scaffolds for tissues that would have the similarity to natural tissues in terms of stiffness, flexibility and endurance. Polyesters of citric acid and diols are promising materials for tissue scaffolds. They are characterized by simplicity of synthesis, use of low-cost and non-toxic monomers as well as ease of controlling properties of obtained products by polymerization process operating conditions. Many attempts at modification of polyesters based on citric acid with natural polyols such as xylitol and mannitol have been observed in recent years. Synthetic polyesters can also be modified with vegetable oil-based polyols being diverse in terms of hydroxyl number and functionality, which leads to change of mechanical properties of obtained polyesters. In this work, the effect of rapeseed oil-based polyols addition on the properties of citric acid-based polyesters has been investigated. It has been found that modification with polyols leads to improvement of tensile strength of obtained materials and additionally in reduction of elongation at break values. However, the modification had no significant influence on swelling properties of achieved polyesters.