Thermoplastic copolyesters morphology

The effect of °Co y-ray irradiation on the mechanical properties, surface morphology, and fractography of blends of plasticized PVC and thermoplastic copolyester elastomer, Hytrel (E.I. Du Pont de Nemours Company, Inc., Wilmington, Delaware), have been studied by Thomas et al. [445]. Radiation has two major effects on the blend cross-linking of the Hytrel phase and degradation of PVC phase. Both effects are found more prominent at higher radiation dose. 

Keyiuords Thermoplastic copolyester elastomers, polyfether ester)s, polyfester ester)s, morphology, mechanical properties, biodegradation, TPEE blends, TPEE recycling... 

Cai F and Isayev A I (1993), D5mamic vulcanization of thermoplastic copolyester elastomer/nitrile rubber alloys II. Rheology, morphology and properties, J Blast Blast 25 249-265. 

S. Saikrasun, S. Bualek-Limcharoen, S. Kohjiya, and K. Urayama. Thermotropic liquid-crystalline copolyester/thermoplastic elastomer in situ composites. I. Rheology, morphology, and mechanical properties of extruded strands. J. Appl. Polym. ScL, 89 2676-2685, 2003. 

Saikrasun S, Bualek-Limcharoen S, Kohjiya S, Urayama K. Thermotropic liquid-crystalline copolyester (Rodrun LC3000)/thermoplastic elastomer (SEBS) in situ composites II. Mechanical properties and morphology of... 

The underlying morphology will have a large effect on the physical properties. The soft phase is usually the continuous phase to maintain the elastomeric behavior of the material. In materials that have crystalline hard segments, such as copolyesters and polyurethanes, both phases are essentially continuous. Thermoplastic elastomers almost never have the soft segment as the isolated phase and the hard segment as the continuous phase. The most... 

Skin/core morphologies are common in blends of LCP s and thermoplastic polymers and they play a significant role in defining the properties of both extruded and injection molded samples. Usually, LCP s in the skin have a higher degree of orientation than in the core when the blends are extruded or injection molded (Husman et al. 1980 Hedmark et al. 1989 Lee 1988). Baird et al. (Baird and Mehta 1989 Baird and Sukhadia 1993) observed a skin/core morphology in blends of PA 66 with HBA/HNA and 40 PET/60 PHB and 20 PET/80 HBA copolyesters. More LCP fibers were present in the skin than in the core for both systems. Isayev and Swaninathan (1994) also reported shell-core structure in the fracture surfaces of injection molded blends of HNA/HBA liquid crystalline copolyesters and poly (etherimide). 

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