Fabrication of Polymer Structure among Fibrous Structure of Poly(lactic acid) Gel and Improvement of Physical Properties

Polymer structure of a block copolymer of poly(l-lactic acid) (PLLA) and polystyrene (PS) is formed among a fibrous structure of PLLA inducing the gelation of PLLA in N,N-dimethylformamide (DMF). The results of static and dynamic light scattering show the formation and growth of aggregates of the block copolymer (PLLA-b-PS) to form aggregates in DMF. The gels formed by the fibrous structure of PLLA in DMF are immersed in DMF solutions of PLLA-b-PS to allow the PLLA-b-PS chains to penetrate among the fibrous structure. The morphology of PLLA-b-PS in the gel is observed by field emission scanning electron microscopy. Viscoelastic measurements of the gel before and after the immersion indicate that the structure of the PLLA-b-PS elevates the flow temperature.