Tensile Mechanical Behavior and Bioactivity of PLA/PCL Biopolyester Threads for Suture

In this paper the mechanical tensile static test of threads both in o-knot of blends made by two biopolyesters, polylactic acid (PLA) and poly(ɛ-caprolactone) (PCL), compatibilized with a triisocyanate (T) in a low amount (1 phr, per hundred resin), and high amount, 5 phr, is performed. The highest mechanical strength of the PLA/PCL/T threads is of about 30 MPa. PLA, PCL, and T are mixed in a twin extruder and the resulting blend is spinnable by a melt spinning process in order to produce thin threads of about 0.3 mm diameter. Compatibilizing filler improves the mechanical performance of the PLA/PCL blend for the chemical branching and/or cross-linking reactions induced among the two typically immiscible biopolyesters. Chemical reactions link PLA with PCL, whose macromolecular structure complexity grows with the filler load. Blended biopolymers can be considered promising biomaterials because they seem to be bioactive and able to inhibit bacterial growth.