The effect of coagulant on the structure and properties of poly(p-phenylene benzobisthiazole) fibers [PBZT]

✍ Scribed by M. A. Rakas; R. J. Farris

• Publisher: John Wiley and Sons
• Year: 1990
• Tongue: English
• Weight: 936 KB
• Volume: 40
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/app.1990.070400518

✦ Synopsis

Abstract

Fibers spun from anisotropic solutions of a lyotropic rigid‐rod polymer, poly(para‐phenylene benzobisthiazole) [PBZT], were coagulated into homogeneous nonsolvents including a solution of 18% iodine/82% ethanol, ethanol, and water. The effect of these coagulants on the structure and mechanical properties of the PBZT fibers was studied. Structural and mechanical studies were performed on as‐spun fibers. Wide‐angle X‐ray diffraction techniques have shown that fibers coagulated in the presence of iodine anions had d‐spacings that were unique, as well as d‐spacings that were characteristic of PBZT or iodine anions. Tensile and shear properties were highest in a fiber having a spin/draw ratio of 3 which contained 19.5% iodine species by weight. For these fibers, an average tensile strength of 2.2 GPa and a torsional modulus of 1.14 GPa was recorded. For fibers having this spin/draw ratio, and undergoing no post‐processing heat treatment or tension drying, these values are much higher than would be expected.