IN OBTAINING polycarbonates formed by interracial condensation, it has been suggested that tertiary amines and salts of quaternary ammonium bases, the use of which makes it possible to obtain high molecular weight polycarbonates [1], should be used as catalysts. In reference [2], the suggestion was expressed that tertiary amines form salts of N,N-carbonyldiamine [(NRaCONRa)~+Clz -] with phosgene, and that these salts transfer from the aqueous into the organic phase and react with aliphatic-aromatic oxy-compounds with the formation of neutral esters, esters of chlorocarbonic acid and free amine. However, such a mechanism cannot explain the difference in effect of the various amines and salts of quaternary ammonium bases on the yield and molecular weight of the polycarbonates formed. Moreover, this cannot explain the effect of the concentration of the tertiary amine on the yield and molecular weight of the polymers. I f the action of the catalyst leads only to a retardation in the hydrolysis of phosgene, then it is not clear why the optimum amount of phosgene required during the synthesis is considerably greater than the theoretical amount, nor is it clear what the role is of the catalyst when it is added after the introduction of phosgene into the reaction system. We have tested t h e following compounds as catalysts during the synthesis of polycarbonates: triethylamine (I), triethylbenzyl ammonium chloride (II), dlmethylphenylbenzyl ammonium chloride (III), tetraethyl ammonium chloride (IV), tetraethyl ammonium bromide (V), tetrabutyl ammonium iodide (VI), triethylmethyl ammonium bromide (VII), and hexamethylene tetramine (VIII). The results obtained in the synthesis of the polycarbonate from 2,2-di-(4-oxy3-methylphenyl)propane with the use of these catalysts are shown in Table 1. From Table 1 it can be seen that the best results were obtained with the use of catalysts I and II , and somewhat poorer results by the use of catalyst I I I . With the aim of clarifying the behaviour of the catalysts in the reaction system, we qualitatively determined the solubility of the catalysts in the solvent and we followed the changes which took place in the catalyst solution on adding
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