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The influence of 2,4,6-trimethylphenol (2,4,6-TMP) -a by-product of 2,6-dimethylphenol (2,6-DMP) preparation -on the process of poly(phenylene oxide) (PPO) synthesis is presented. Synthesis of the polymer was carried out with solution and precipitation method. 2,4,6-TMP was used in the amount up to 2.2 wt % in both processes. The molecular weights (M n and M w ) and the dispersity (Ð) of the polymers obtained were determined by gel permeation chromatography (GPC). Thermal properties using (DSC, TGA), and the mass melt flow rate (MFR) were also determined. In contrast to the precipitation method, it was found that 2,4,6-TMP had a strong effect on properties of PPO obtained by solution polymerization. Addition of 2,4,6-TMP to the monomer solution caused a decrease in molecular weight of polymers. A change of Ð value and thermal properties were also noticed. An addition of 2,4,6-TMP up to 2.2 wt % to the reaction in the solution polymerization caused increase in MFR, whereas alcohol used in the precipitation polymerization of 2,6-DMP strongly determined properties of the polymer obtained.

The aim of this work was to examine the aminosilane ligands for the copper(II) salts and their application as catalysts for the oxidative polymerization of 2,6-dimethylphenol leading to poly(2,6-dimethyl-1,4-phenylene ether) (PPE) [also known as poly(phenylene oxide) (PPO)] formation. As aminosilane ligands, silane derivatives containing primary and/or secondary amino groups were tested. Among aminosilanes used, PPE was only obtained when N-methylaminopropyltrimetoxysilane (MAPTMS) as a ligand for copper(II) was used. CuCl 2 and CuBr 2 were compared as catalyst precursors for 2,6-dimethylphenol polymerization and influence of N/Cu molar ratio in the range from 80 to 160 on PPE yield and its M w was tested. It was observed, that with increasing N/Cu molar ratio from 80 to 120, both PPE yield and M w increased. PPE with the highest M w was obtained when CuBr 2 -MAPTMS as a catalyst was used. At N/Cu molar ratio equal to 160, a decrease in PPE M w obtained with use of both precursors and decrease in PPE yield for CuCl 2 -MAPTMS catalyst were noticed. The condensed nanoorganosilicon particles of spherical shape well dispersed in PPE were determined in the polymer matrix. The UV-Vis studies showed that, strong ligand field of the aminosilane ligand easier electron transfer from monomer to Cu(II) and thus polymerization facilitate.

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