Oxidative coupling copolymerization for synthesis of poly(phenylene oxide) containing allyl groups in water
Abstract
Poly(2-allyl-6-methyl-1,4-phenylene-co-2,6-dimethyl-1,4-phenylene oxide)s (allyl-PPOs) were synthesized through oxidative coupling copolymerization of 2,6-dimethylphenol and 2-allyl-6-methylphenol in water. The copper(II)/ethylene diamine tetraacetic acid (Cu(II)/EDTA) complex catalyzed copolymerization was conducted in alkaline aqueous solution in an oxygen atmosphere. And low-molecular-weight allyl-PPOs with relatively narrow molecular weight distributions were obtained. FTIR, 1H and 13C NMR spectroscopies were employed to identify the structure of allyl-PPOs. Crosslinking reactions of allyl-PPOs were carried out under UV treatment with the presence of a photo initiator. It is environmentally benign to synthesize allyl-PPO in aqueous solution. And the residual copper ions in the product obtained in water medium were much lower in number than those in the product synthesized in organic solvent. The dielectric constant and dissipation factor of the product produced in this way were very low.