A series of high-molar-mass and controlled-molar-mass poly(arylene ether ketone)s were synthesized based on bis(p-fluorobenzoyl)aryl monomers and 4,4'-isopropylidenediphenol. The central aromatic unit of the activated bishalide was varied to include 1,4-phenylene, 2,5-thiophene and 1,3-phenylene, which changed the exocyclic bond angle from 180 ° to 148 ° to 120 °, respectively. The decrease in exocyclic bond angle decreased the glass transition temperature of the uncontrolled-molar-mass polymers from 166°C to 156°C to 154°C, respectively. The T~ of the controlled-molar-mass polymer decreased from 160°C to 147°C to 149°C for the same series, i.e. poly(1,4-BFB-BisA), poly(BFTh-BisA) and poly(1,3-BFB-BisA), respectively. The discrepancy between the two series was interpreted in terms of molar-mass differences. The thermal stability of the three polymers also decreased in the order of decreasing exocyclic bond angles. Young's modulus increased as the exocyclic bond angle was decreased, which is explained in terms of the activation theory of Eyring. These three polymers represent a new approach for the study of structure-property relationships in poly(arylene ether ketone)s.
Посилання на статтю:
Thiophene-based poly(arylene ether ketone)s: 2. Thermal and mechanical properties of amorphous systems using bis(p-fluorobenzoyl)aryl monomers* / A. B. Brennant and Y. Q. Wang // Polymer. – 1993. – Vol 34. – P. 807-812.