LCP/PEN blends

Figure 20.11 The tensile strength of the LCP/PEN blends as a function of the LCP content at draw ratios of 10 ( ) and 20 ( ) [13]. From Kim, S. H., Hong, S. M., Hwang, S. S. and Yoo, H. O., J. Appl. Polym. Sci., 74, 2448-2456 (1999), Copyright (1999, John Wiley Sons, Inc.). This material is used by permission of John Wiley Sons, Inc...

Figures 20.13 and 20.14 describe the effect of dibutyltin dilaurate (DBTDL) on the tensile strength and tensile modulus for the 25/75 LCP/PEN blend fibers at draw ratios of 10 and 20 [13]. As expected, the addition of DBTDL slightly enhances the mechanical properties of the blends up to ca. 500 ppm of DBTDL. The optimum quantity of DBTDL seems to be about 500 ppm at a draw ratio of 20. However, the mechanical properties deteriorate when the concentration of catalyst exceeds this optimum level. From the previous relationships between the rheological properties and the mechanical properties, it can be discerned that the interfacial adhesion and the compatibility between the two phases, PEN and LCP, were enhanced. Hence, DBTDL can be used as a catalyst to achieve reactive compatibility in this blend system. This suggests the possibility of improving the interfacial adhesion between the immiscible polymer blends containing the LCP by reactive extrusion processing with a very short residence time.

Table 20.6 The kinetic parameters of the LCP/PET and LCP/PEN blends at each temperature [44], From Park, J. K., Park, Y. H., Kim, D. J. and Kim, S. H., Crystallization Kinetics of TLCP with polyester blends , J. Korean Fiber Soc., 37, 69-76 (2000). Reproduced by permission of The Korean Fiber Society...

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