Premium
Rheological behavior and prediction for blending conditions of a thermotropic liquid crystalline polyester with nylon
Author(s) -
Wang Huimin,
Lee Kah Wee,
Chung, TaiShung
Publication year - 2000
Publication title -
polymers for advanced technologies
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.61
H-Index - 90
eISSN - 1099-1581
pISSN - 1042-7147
DOI - 10.1002/1099-1581(200004)11:4<153::aid-pat949>3.0.co;2-x
Subject(s) - materials science , thermotropic crystal , rheology , nylon 6 , activation energy , polyester , viscosity , nylon 66 , polymer , composite material , polymer chemistry , chemical engineering , liquid crystalline , organic chemistry , chemistry , polyamide , engineering
The dynamic rheological behavior of a liquid crystalline polymer (LCP), Vectra™ A, and nylons was investigated. The viscosities of nylon 66 and nylon 6 decrease slowly with an increase in temperature, while the viscosity of Vectra A drops dramatically at 280 °C, but remains slightly changed above 300 °C. At constant frequency and above 300 °C, the mean value of the activation energy of Vectra A is about 87.0 kJ/mole, but jumps to a much higher value of about 407.0 kJ/mole if the melt temperature is below 300 °C. The activation energy of Vectra A above 300 °C is lower than nylon 66, which shows that the viscosity of nylon 66 has a greater temperature dependence than Vectra A. The viscosity ratio of Vectra A to Nylon 66 is less than 1 at temperatures higher than 290 °C, which indicates that Vectra A can form the fibrils in the nylon 66 matrix and reinforce nylon 66 when blending them above this temperature. Experimental data confirm our prediction. Copyright © 2000 John Wiley & Sons, Ltd.