Preparation of blend anti-adhesion films and the corresponding hydrolytic behaviors

Abstract

Postoperative adhesions (POA) remain a significant concern following surgeries, especially the surgeries of complex geometries. The PLA-PEG (PELA) copolymer films have been proved to be efficient in relieving POA. However, proper degradation rate and suitable film strength cannot meet simply by adjusting the ratio of LA/EG in polymerization. In this article, we have prepared the blend membranes of PLGA and PELA copolymers and investigated their hydrolytic behaviors and mechanical properties. Among the prepared membranes, the control sample PLGA (95/5) film displays the highest yield strength (48 Mpa) and the lowest elongation at break (129%) under room temperature. It undergoes bulk degradation while PELA copolymer films undergo both bulk and surface degradation. Introduction of PELA (50:50) or PELA (65:35) into less hydrophilic copolymers (PLGA-95:5, PLA-PEG-95:5) can effectively improve the mechanical properties with the breaking elongation higher than 400% for all the blend membranes. However, only blend films with compositions of similar segment structures (PELA-95:5/65:35, PELA-95:5/50:50) are able to avoid burst degradation of more hydrophilic composition, which effectively avoid the porous structures during degradation according to SEM graphs. At last, the interaction of the two blended copolymers will adjust the film degradation rate to the point between that of two blends if they are similar in segment structures. Therefore, blending of compatible components can not only achieve well mechanical property but also improve their degradation behaviors.