Mechanical properties of silk fiber reinforced composites

초록

Polymer composites consisting of continuous reinforcing fibers embedded in polymeric matrices have been extensively used over the last decades due to their high strength per weight ratios.1 Silk fibers have outstanding mechanical properties. These fibers are insoluble in organic solvents and water, are biocompatible and exhibit slow biodegradation in vitro and in vivo due to the hydrophobic nature of the protein and the presence of a high content of β-sheet structure.2 In this study, they are incorporated into commercially available biodegradable polymers such as poly(butylene succinate) (PBS), poly(butylene succinate adipate) (PBSA), poly(ε-caprolactone) (PCL) and poly(L-lactic acid) (PLLA) with the main objective of improving the mechanical properties of them and reducing the cost of the final products. We designed various kinds of silk textile for the fabrication of sandwich-like composites; silk textiles between two polymer layers. The effect of different kinds of textiles in composites was determined on their mechanical properties. We also improved the adhesion between the matrix polymers and the fibers by physical or chemical modification of fiber surface. The adhesion property was measured by microdroplet debonding test.3 Figure 1 shows the fracture surface of the composites observed by scanning electron microscope (SEM).