Studies on Dry-Jet-Wet Spun Polyurethane Fibers. II.Effect of Polyurethane Shore Hardness on Spinnability and Fiber Properties

摘要

This article reports a study on the spinnability of three different ester type thermoplastic polyurethanes (TPUs) with shore hardness 75A, 85A, 92A using the dry-jet-wet spinning method. The three grades have been analyzed by FTIR, GPC, and 1H-NMR to establish the difference among them. FTIR indicated that all the three grades were chemically similar and GPC suggests that molecular weight increased with increase in shore hardness. Compositional analysis indicates that the hard segment content increases with increase in shore hardness. Shear viscosity of TPU dope solution increases with increase in shore hardness. Of the three different grades of TPUs studied, only the grades with shore hardness of 85A and 92A are spinnable under the experimental conditions. The fiber properties of three different grades have been compared. Fibers spun with the shore hardness of 85A have good elastomeric properties compared with the other two grades. Lab spun fibers have also been compared with the commercial spandex fibers.