Modified poly-(2,6-dimethyl-p-oxyphenylene), process for preparing it and its use in membranes for separating gas mixtures.

摘要

A modified, amorphous poly-(2,6-dimethyl-p-oxyphenylene) (PPO) having a glass transition temperature (Tg) comprised within the range of temperatures of from 170 to 220 DEG C, contains in its macromolecule: units functionalized with ethyleneoxy-trialkyl-silyl moieties <CHEM> units functionalized with trialkyl-silyl moieties <CHEM> <CHEM> units functionalized with hydroxy-ethylene moieties <CHEM> together with unaltered 2,6-dimethyl-p-oxymethylene units: <CHEM> Such a modified PPO is prepared by metallating PPO with a metallating agent and causing such a metallated PPO to react with ethylene oxide and a trialkyl-silyl-halide in the stated sequence. The use of modified PPO for the preparation of flat, also asymmetrical, membranes, useful in the processes of separation of gas mixtures, is disclosed.