Properties of polypyromellitimides containing phosphorus



The paper deals with the synthesis and characterization of seven polypyromellitimide samples having varying contents of phosphine oxide and ether linkages in the backbone with pendant maleimido groups. Curing characteristics and thermal stability of polymers were evaluated by differential scanning calorimetry and dynamic thermogravimetry. It was observed that an increase in pendant maleimido groups resulted in an increase in the heat of polymerization. Char yield also increased with increase in phosphorus content. Conductivity and dielectric parameters were also evaluated. The mechanism of conduction was found to be a combination of electronic and ionic type.