Simulation Study of Thermotropic LCPs and Prediction of Normal Stress Difference at High Shear Rate
-
A. Rahman
, R. K. Gupta , S. N. Bhattacharya , S. Ray und F. Costa
Abstract
The shear viscosity and normal stress difference of two filled and two unfilled thermotropic liquid crystal polymer (TLCPs) were studied. The rigid and rod like molecules of TLCPs orientate differently at different shear rates. Under low shear rate, the molecules tend to align in the direction of the flow but also tumble and wagging on their own axis. The abnormal orientation of the molecules also depends upon temperature, fillers contents, aspect ratio and elastic nature of LCP molecules. These behaviors lead to unusual rheological properties of LCPs, such as negative first normal stress difference for filled LCPs at low shear rates. But with the increase of shear rate, the molecules are oriented in the direction of flow, which lead to isotropic flow at high shear rates. The complicated rheological properties and characteristic anisotropic properties of LCPs are modelled by recently developed Leonov's viscoselastic constitutive equations. Simulation has been carried out using Mathematica software and the characteristic anisotropic properties of LCPs have been identified. The experimentally measured viscosities at high shear rate have been compared with model predictions. Moreover, the normal stress differences using at high shear rates have been estimated using Leonov's model, which is experimentally not accessible.
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© 2013, Carl Hanser Verlag, Munich
Artikel in diesem Heft
- Contents
- Contents
- Regular Contributed Articles
- Use of the Taguchi Method for Optimization of Poly (Butylene Terephthalate) and Poly (Trimethylene Terephthalate) Blends through Injection Molding
- CFD Analysis of the Frame Invariance of the Melt Temperature Rise in a Single-screw Extruder
- Simulation Study of Thermotropic LCPs and Prediction of Normal Stress Difference at High Shear Rate
- Study on Mechanical, Thermal Properties and Morphology of Biodegradable Poly(butylene succinate)/Nano-TiO2 Composites
- Preparation and Characterization of Bamboo Fibers Coated with Titanium Urushiol and its Composite Materials with Polypropylene
- Effect of the Mandrel Rotation Speed and Inner Wall Cooling Rate on the Performance and Structure of Polypropylene Block-Copolymer Pipe
- Modification of Liquid Oxygen Compatibility of Bisphenol F Epoxy Resin
- Pressure Variation during Interfacial Instability in the Coextrusion of Low Density Polyethylene Melts
- The Effects of Processing Parameters on the Residual Wall Thickness Distribution at the Sharp Angle Corner of Water Assisted Injection Molded Parts
- The Influence of Extrusion Conditions on Mechanical and Thermal Properties of Virgin and Recycled PP, HIPS, ABS and Their Ternary Blends
- Influence of Mold Temperature on Mold Filling Behavior and Part Properties in Micro Injection Molding
- On the Pressure Dependency of the Bagley Correction
- PPS News
- PPS News
- Seikei Kakou Abstracts
- Seikei-Kakou Abstracts
Artikel in diesem Heft
- Contents
- Contents
- Regular Contributed Articles
- Use of the Taguchi Method for Optimization of Poly (Butylene Terephthalate) and Poly (Trimethylene Terephthalate) Blends through Injection Molding
- CFD Analysis of the Frame Invariance of the Melt Temperature Rise in a Single-screw Extruder
- Simulation Study of Thermotropic LCPs and Prediction of Normal Stress Difference at High Shear Rate
- Study on Mechanical, Thermal Properties and Morphology of Biodegradable Poly(butylene succinate)/Nano-TiO2 Composites
- Preparation and Characterization of Bamboo Fibers Coated with Titanium Urushiol and its Composite Materials with Polypropylene
- Effect of the Mandrel Rotation Speed and Inner Wall Cooling Rate on the Performance and Structure of Polypropylene Block-Copolymer Pipe
- Modification of Liquid Oxygen Compatibility of Bisphenol F Epoxy Resin
- Pressure Variation during Interfacial Instability in the Coextrusion of Low Density Polyethylene Melts
- The Effects of Processing Parameters on the Residual Wall Thickness Distribution at the Sharp Angle Corner of Water Assisted Injection Molded Parts
- The Influence of Extrusion Conditions on Mechanical and Thermal Properties of Virgin and Recycled PP, HIPS, ABS and Their Ternary Blends
- Influence of Mold Temperature on Mold Filling Behavior and Part Properties in Micro Injection Molding
- On the Pressure Dependency of the Bagley Correction
- PPS News
- PPS News
- Seikei Kakou Abstracts
- Seikei-Kakou Abstracts