Synthesis and Investigation of Properties of Polynorbornenes with Bromoanthracene Substituent

A new monomer of the norbornene series, containing a substituent with 9,10-dihydroanthracene fragment and a bromine atom has been synthesized with a yield of 47% using the Diels–Alder reaction between norbornadiene-2,5 and 2-bromanthracene. Its metathesis and additive polymerizations have been investigated. The sorption properties of the two obtained polymers, as well as the gas transport properties of the metathesis polymer, have been investigated. It has been shown that the presence of polar bromine atom in the side chain does not affect the properties of the polynorbornenes with 9,10-dihydroanthracene moiety: like similar polymers without bromine atoms, the synthesized polymers have exhibited a moderate level of gas permeability, a large free volume, and a large specific surface area (540 m2/g in the case of the additive polymer). The polymer obtained by metathesis polymerization has shown slightly lower values of ideal gas separation selectivity of CO2-containing gas pairs compared to the unsubstituted analog, but higher O2/N2 selectivity. Such bromine-containing polynorbornenes may be of potential interest as materials for the storage and separation of gases, the properties of which can be tuned using polymer-analogous transformations.