Abstract
Undrawn poly(ethylene terephthalate) (PET) monofilaments were surface-crystal lized through contact with dimethylformamide (DMF) using a continuous method. The specific surface area (SSA) of the resulting bimorphic filaments determined by inverse gas chromatography was found to be several hundred times the SSA of the starting material. The cavitated surface morphology has limited thermal stability, thermal annealing and hot drawing causing a monotonic decrease in SSA with in creasing temperature; however, scanning electron micrographs show that a substantial part of the surface structure is preserved even after annealing at 180°C. In addition, though hot drawing produces filaments with lower surface areas that are found for undrawn filaments, the areas are more thermally stable. The presence of small amounts of water or methanol in the DMF increased the SSA of the filaments, but amounts larger than several volume percent brought about a rapid decrease in SSA.
Get full access to this article
View all access options for this article.
