Synthesis of adamantyl and benzoxazole substituted poly( m-phenylene)s via the nickel catalysed coupling of aryl chlorides

• Published in: Polymer (Guilford) 1996-08, Vol.37 (16), p.3771-3774
• Main Authors: Mathias, Lon J., Tullos, Gordon L.
• Format: Article
• Language: English
• Subjects: adamantyl; Applied sciences; benzoxazole; Exact sciences and technology; nickel catalysed; Organic polymers; Physicochemistry of polymers; poly( m-phenylene)s; Polymers with particular properties; Preparation, kinetics, thermodynamics, mechanism and catalysts
• ISSN: 0032-3861; 1873-2291
• DOI: 10.1016/0032-3861(96)00195-4

Poly( m-phenylene)s (PMP) with 1-adamantyl and 5-methyl-2-benzoaxozole or 2-benzoaxazole substituents ortho and meta to the backbone were synthesized via the nickel(0) catalysed dehalogenative coupling of aryl dichlorides. Ortho substituted polymers, which can have head-to-head and head-to-tail linkages, displayed better solubility in common organic solvents. The benzoxazole-containing PMPs exhibited excellent thermal stability in air by dynamic t.g.a. (thermogravimetric analysis) with values of 5% weight loss of 530–600°C while the adamantyl-substituted polymer showed a much lower thermal stability (5% weight loss at 370°C). All benzoxazole-functionalized polymers exhibited relatively high glass transition temperatures of 221–250°C. No glass transition was observed for the adamantyl-substituted PMP before the onset of decomposition at 350°C. Polymer number average molecular weights ranged from only 2000–4500 relative to polystyrene standards, indicating the need for further development of polymerization conditions.