Poly Lactic Acid (PLA) Fibres: Different Solvent Systems and Their Effect on Fibre Morphology and Diameter

摘要

Mainly poly (lactic acid) (PLA) is a biocompatible thermoplastic aliphatic polymer. Among all of the biodegradable polymer polylactic acid (PLA) is very significant on biomedical and biocompatible field. For the selection of an appropriate non-hazardous solvent or solvent system it's important to determine the rheological properties and electrospinnability of the solution and the morphology of nanofibres. In this paper we have tried to investigate the solution of poly lactic acid (PLA) in various pure solvents and binary-solvent systems and their effect on different solution properties of nanofibre morphology and diameter. We observed the Nanofibre morphology by scanning electron microscopy (SEM). Compared to other solvent we found acetone/dimethylformamide solvent system gave the highest fibre productivity and finest defect-free nanofibres. Therefore, we also used various solvent ratio for more details. Also the polymer concentration in the solvent has great effect on nanofibre morphology and solution properties. Further investigation of the effect of the PLA concentration on the elastic (G') and the plastic (G") moduli showed a sudden increase of the elastic moduli (G') at the critical chain entanglement concentration. The results showed that the solvent properties, boiling point, viscosity, conductivity and surface tension, have a significant effect on process productivity, morphology and diameter distribution of the PLA nanofibres.