Transient shear and elongational behavior of blends of PET with a LCP |
| |
Authors: | Lucineide Balbino da Silva Marcelo Massayoshi Ueki Marcelo Farah Vitor Manuel Coelho Barroso João Manuel Luis Lopes Maia Rosario Elida Suman Bretas |
| |
Institution: | 1. Department of Materials Engineering, Universidade Federal de S?o Carlos, 13565-905, S?o Carlos, SP, Brazil 2. Institute for Polymers and Composites, Department of Polymer Engineering, University of Minho, 4800-058, Guimar?es, Portugal
|
| |
Abstract: | Blends of polyethylene terephthalate (PET) with a liquid crystalline polymer (LCP) and a compatibilizer were produced by twin
screw extrusion and injection molding. Transesterification and compatibilization studies were made in a torque rheometer.
The morphology of the injection-molded plaques was studied by scanning electron microscopy. The blends shear growth function
was measured in a cone and plate rheometer. The elongational growth function
was measured in a modified rotational rheometer. Transesterification was observed in the PET/LCP/compatibilizer 95/5/0 blend.
The injection-molded plaques displayed the usual “skin-core” morphology. All the blends were highly shear-thinning, even at
low shear rates; thus, a zero-shear viscosity could not be calculated. The compatibilized blend had the highest shear viscosity
of all the blends, confirming the strong PET/LCP interphase and the effectiveness of the compatibilizing agent. On the other
hand, the 90/10/0 blend had the lowest shear viscosity. All the blends showed strain softening behavior, similar to the PET.
The 90/10/0 blend had the highest elongational growth function, while the 95/5/0 had the lowest. The compatibilized blend
had an intermediate behavior between both blends. |
| |
Keywords: | Liquid crystalline polymer Poly(ethylene terephthalate) Blends Elongational viscosity Shear viscosity |
本文献已被 SpringerLink 等数据库收录! |
|