The synthetic route to polyetherimides by displacement of nitro‐groups from disubstituted bis‐imides by the dianion of bisphenols are described. The prepration of bis‐imides and bisphenol dianions, their polymerization, and some of the properties of the polymers are presented in detail. The 13C‐NMR spectra of intermediates and products were used to establish compositions and determine molecular weights.

SynopsisThe limiting oxygen index (LOI) has been determined for each of a large number of silicone-containing resins, principally dimethylsiloxane (DMS) block polymers varying widely in DMS content and hard block type. A synergistic enhancement in LO1 of varying strength is seen in several families of resins. For the major families explored, the synergism varies with hard block type in roughly the following order: bisphenol-A carbonate and bisphenol fluorenone carbonate > styrene and 2,6diphenyl-l,4-phenylene oxide > bisphenol chloral polycarbonate > methyl methacrylate and phenolphthalein carbonate, the enhancement being nil in the last case. Strength of the synergism is discussed in terms of DMS degree of dispersion, char-forming tendencies, melt viscosity, and other factors.(2) Bisphenol A polycarbonate: block polymers. (3) Bisphenol chloral polycarbonate: block polymers. (4) Phenolphthalein polycarbonate: block polymers. (5) Polystyrene: block polymers. (6) Poly(methy1 methacrylate): block and graft polymers. (7) Poly(2,6-diphenyl-l,4-phenylene oxide): block polymers; blends of homopolymer with block polymers and with silicone gum.

The synthesis of poly(2,6‐diphenyl‐1,4‐phenylene ether), by the oxidative coupling of 2,6‐diphenylphenol has been studied. Procedures were found which demonstrated that polymers of very high molecular weight \documentclass{article}\pagestyle{empty}\begin{document}$ \left( {\overline M _n > 200{\rm 000; }\left[ \eta \right]_{{\rm CHCl}_{\rm 3} }^{25^\circ {\rm C}} > 1.1{\rm }{{{\rm dl}} \mathord{\left/ {\vphantom {{{\rm dl}} g}} \right. \kern-\nulldelimiterspace} g}} \right) $\end{document} could be made with a copper‐amine catalyst system. A low nitrogen‐to‐copper ratio (1 N atom/Cu atom) was necessary to obtain the very high molecular weights under the conditions of these reactions. A variety of amines formed active catalysts; the effectiveness of mono‐ and bis‐ primary, secondary, and tertiary amines were compared. Effects of the type of copper halide, reaction temperature, desiccants, addition rates of 2,6‐di‐phenylphenol, and solvents were also examined. Samples of polymer were isolated at different times during the polymerization. Measurements of viscosity, osmotic pressure, light scattering, gel permeation, phenolic hydroxyl groups, and nitrogen content were made on various samples over a range of intrinsic viscosities of 0.05–0.59 dl/g. A very narrow molecular weight distribution was found for all samples. Hydroxyl endgroup analyses indicated that the concentration of phenolic endgroups per mole of polymer does not change during the polymerization. The presence of some side reactions is indicated by nitrogen analyses. The relationships between the intrinsic viscosity in chloroform at 25°C and M̄n and M̄w are: log [η] = −3.97 + 0.727 log M̄n and log [n] = −3.56 + 0.624 log M̄w.

synopsisCopper-amine catalyst systems which polymerize %methyl-6-phenylphenol to high molecular weight polymer are described. With CuCl and N,N,N',N'-tetramethyl-lJ3butanediamine (TMBD), an intrinsic viscosity of 1.56 dl/g was obtained. Faster r a h of polymerization resulted with a CuBr-TMBD catalyst. Catalysts from other tertiary amines and mixtures of tertiary amines also produced high polymer. Pyridine and diethylamine catalyst were less active. Samples of polymer were isolated at different stages of the polymerization. Measurements of viscosity, osmotic pressure, light scab tering, gel permeation, hydroxyl group;, nitrogen content, y d chemicalLea$ivity were made on the samples. Below a molecular weight value of M , 60,000, M,/M, was 2.0. At higher molecular weights, there was a broadening in molecular weight distribution. No major change in the molar concentration of the "head" endgroups with increasing molecular weight was detected by infrared analysis. However, nitrogen analyses, chemical reactivity studies, and the @,/aw ratio suggested the chemical nature of the "head" end had changed. The relationships between intrinsic viscosity in chloroform at 25OC and a, and a, for unfractionated_pglymer samples are log [q] = -4.26 + 0.84 log and log [q] = -3.86 + 0.701og M,.

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