Synthesis, modification, and characterization of hyperbranched poly(ether ketones)

• Published in: Polymer (Guilford) Vol. 40; no. 23; pp. 6591 - 6596
• Main Authors: Shu, C.-F, Leu, C.-M, Huang, F.-Y
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.11.1999; Elsevier
• Subjects: Applied sciences; Electrophilic aromatic substitution; Exact sciences and technology; Glass transition temperature; Hyperbranched poly(ether ketone); Organic polymers; Physicochemistry of polymers; Polymers with particular structures; Preparation, kinetics, thermodynamics, mechanism and catalysts; Electrophilic aromatic substitution; Hyperbranched poly(ether ketone); Glass transition temperature; Substituent effect; End group; Solution polycondensation; Self condensation; Ether copolymer; Branched copolymer; Experimental study; Thermal stability; Ketone copolymer; Benzoic acid derivatives; Chemical modification; Electrophilic substitution; Carboxylic acid; Preparation; Aromatic copolymer; Alternating copolymer
• ISSN: 0032-3861; 1873-2291
• DOI: 10.1016/S0032-3861(99)00003-8

This report presents the synthesis and chemical modification of hyperbranched poly(ether ketones). The polymer was conveniently prepared by direct polycondensation of an AB 2 monomer, 3,5-diphenoxybenzoic acid, using phosphorus pentoxide/methanesulfonic acid (PPMA) as the condensing agent and solvent. The hyperbranched poly(ether ketone) could be modified via the electrophilic aromatic substitution of the active phenoxy groups at the chain ends with a variety of carboxylic acids. The thermal properties of the hyperbranched poly(ether ketones) depend heavily on the nature of the chain end, with glass transition temperature ranging from −24°C to 180°C. Moreover, the length of the terminal alkyl groups significantly influences the solubility of the hyperbranched poly(ether ketones). By varying the chain ends, hyperbranched poly(ether ketones) soluble in either a polar or nonpolar solvent could be obtained.