Synthesis and properties of poly(1,6-heptadiyne) having a bulky and rigid t-butylbenzoyl group

The polymerization of 4,4-bis(t-butylbenzoylmethy1)-1,6-heptadiyne (BTBH) w as carried out by group 5,6-transition metal catalysts. MoCl5- as well as W Cl6-based catalysts were effective for the cyclopolymerization of BTBH. The polymer structure was analyzed to have conjugated backbone and recurring 5 -membered ring by various spectroscopes. The polymer showed good solubility in common organic solvents. The polymer had good thermal stability and mec hanical property. The oxygen permeability coefficient (PO2) and permselecti vity of oxygen to nitrogen (PO2/PN2) of poly(BTBH) with bulky and rigid t-b utyl benzoyl group were 23.2 barrer and 4.63, respectively.