Synthesis of aliphatic-aromatic polyimides by two-step polymerization of aliphatic dianhydride and aromatic diamine

Aliphatic-aromatic polyimides were synthesized by polycondensation reaction in solvent. The effects of variables such as the kind of solvent, reaction time and temperature, and monomer concentration were investigated in detail on the reaction of 1,2,3,4-butanetetracarboxylic dianhydride and 4,4′-oxydianiline or 4,4′-diaminodiphenylmethane. The viscosities of polyimides were between 0.22 and 0.46 dL/g. The polyimides were soluble in some aprotic polar solvents, such as N,N′-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), dimethylsulfoxide (DMSO), and N,N′-dimethylformamide (DMF). They began to decompose at 380-410°C in air, and 10% weight loss temperatures were 430-450°C.