Structure, crystallization, and properties of poly(aryl ether ether ketone ketone)s containing meta-phenyl links and their copolymers

✍ Scribed by Yang-Chuan Ke; Zhi-Jie Fang; Jun-Zuo Wang; Zhong-Wen Wu

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 650 KB
• Volume: 61
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/(sici)1097-4628(19960822)61:8<1293::aid-app9>3.0.co;2-f

✦ Synopsis

SYNOPSIS

Poly(ary1 ether ether ketone ketone)s (PEEKK) containing rneta-phenyl links and their series of copolymers were synthesized and investigated by both X-ray and differential scanning calorimetry (DSC) methods. Results showed that the heat properties of this kind of copolymer depended greatly on the content of rneta-phenyl links in the copolymer system, in which occurred the lowest melting point. Results from X-rays showed that PEEKK containing rnetu-phenyl links had no (111) crystal face diffraction. These proved that metaphenyl links had introduced asymmetrical factors, which had produced poor crystal structure and difficulty in crystallization. Even so, the modification of PEEKK by introducing the rnetu-phenyl links improved the polymer composite performances, e.g., the copolymer Mz, which kept performances close to PEEKK but better than PEEK. DSC results of M, showed that its Avrami number ( n ) was 1.5 and its crystal grew fibrously from isothermal crystallization of the melting state, while for the nonisothermal crystallization from the melting state, n was 4.4 to the spherical crystal growth, and the activation energy ( A E ) of crystallization was 184 kJ/mol, which was less than the AE of 296 kJ/mol for PEEKK crystallized from the nonisothermal melting state. When M2 was isothermally crystallized from the rubber state, its n was 2 to the disklike crystal growth, while its n was 4.6 to the spherulitic crystal growth for the nonisothermal crystallization state of melting. The isothermal crystallization process was different from the nonisothermal process in the crystal nucleation and growth for Mz.