| 摘要 |
<p>The invention relates to a new process for the production of polyphenylene oxides corresponding to the following formula (I): < IMG > (I) in which R may be the same or different at each position and represents hydrogen, an alkyl radical containing from 1 to 4 carbon atoms or an aryl radical containing up to 6 carbon atoms, represents a group of the formula R1-?-R1, where R1 represents hydrogen or an alkyl radical containing from 1 to 4 carbon atoms, -O-, -?-, -S- or -SO2-, and m and n are integers from 1 to 200, characterised in that a mixture of phenols corresponding to the following formulae (II) and (III): < IMG > (II) < IMG > (III) in which R may be the same or different at each position and has the same meaning as in formula (I), is reacted with oxygen in an organic solvent in the presence of a catalyst at a temperature of from -80 to 100.degree.C and optionally under elevated pressure. Polymer blocks containing two functional terminal groups and having a high glass transition temperature may be obtained by the process according to the invention. These blocks may be reacted, for example, with acid chlorides, such as phosgene or terephthaloylchloride, with diisocyanates, with carbonates and with other polymer blocks to form high molecular weight compounds. Materials produced from these high molecular weight compounds are distinguished by their high dimensional stability under heat.</p> |
