Synthesis and chemical modification of poly(butylene succinate) with rutin useful to the release of silybin

Poly (butylene succinate) (PBS) is a biodegradable polyester, which can be obtained from renewable sources. The chain extension technique was used, aiming to promote an increase in the molecular weight of PBS, besides improving its thermal, mechanical and rheological properties. To the best of our knowledge, the use of rutin as a natural chain extender has never been tested. In addition, this chain extension was compared to the ordinary one, using castor oil. Thus, the present work aimed to prepare and compare the properties of PBS extended by the addition of these mentioned chain extenders. In addition, different reaction conditions were tested and the obtained results allowed us to infer that both chain extenders produced an increase of molecular weight, viscosity and thermal resistance. In spite castor oil be a more efficient chain extender, the use of a small amount of rutin (1 wt%) produced an increase in the viscosity of PBS of around 100%. In addition, the molecular weight increased by 36% and the crystallinity presented a reduction of 7%. In addition, the polymer modified with rutin was tested as a silybin release system. The material extended using rutin was able to reduce the release of silybin, in comparison to the one from PBS, in 25.7%.