Correlation between physical properties and conformational rigidity of some aromatic polyimides having pendant phenolic groups

Soluble polyimides based on an aromatic diamine containing pendant phenolic group and four different dianhydrides have been synthesized by two-step polycondensation reaction in solution. The polyimides were easily soluble in polar organic solvents and even in less polar solvents and showed high thermal stability, with initial decomposition temperature being above 420 A degrees C. Monte Carlo method was used to calculate conformational rigidity parameters of these polyimides. Some physical properties such as solubility, glass transition temperature and initial decomposition temperature were investigated and compared with those of related polyimides which did not contain any pendant groups based on the same dianhydrides and a diamine without pendant phenolic group. All data were discussed in relation to the rigidity of the chain.