Studies on co[poly(ethylene terephthalate-p-oxybenzoate)] thermotropic copolyester: Thermomechanical and thermodynamic properties

✍ Scribed by Ted-Hong Shinn; Chen-Chong Lin

• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: English
• Weight: 495 KB
• Volume: 58
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/app.1995.070581108

✦ Synopsis

A series of co[poly(ethylene terephthalate-p-oxybenzoate)] thermotropic copolyesters were prepared by the copolymerization of poly(ethy1ene terephthalate) (PET) as moiety (11) and p-acetoxybenzoic acid (POB) as moiety (I). The polymeric products obtained were subjected to solid-state polymerization. Characterization of the copolyesters by thermomechanical analysis shows that properties such as the coefficient of thermal expansion, transition temperature, and maximum softening rate temperature varied directly as a function of composition as well as did solid-state polymerization time. All thermomechanical data were found to increase with the solid-state polymerization time due to the increase in the degree of polymerization and the effect of annealing. The coefficient of thermal expansion behaves in a manner that is interpretable by the crystalline state of the copolyester. The relationship between the free-volume fraction and thermodynamic properties is further correlated for a more comprehensive discussion on its molecular arrangements.