5-Aminoisophthalic acid (AIPA) can be used as a starting material to prepare: Poly(5-aminoisophthalic acid) by oxidative polymerization reaction. Poly(benzimidazole-co-aniline) (PBIANI) by condensation polymerization with 3,3′-diaminobenzidine via poly(5-aminoisophthalic acid) as a key intermediate. It can also be used as a blended material with polyvinylalcohol to prepare silica-functionalized composite membranes for diffusion dialysis applications. AIPA based metal-organic framework (MOF) can be modified with various functional groups for different applications. 5-Aminoisophthalic acid (AIPA) can be used as a starting material to prepare: Poly(5-aminoisophthalic acid) by oxidative polymerization reaction. Poly(benzimidazole-co-aniline) (PBIANI) by condensation polymerization with 3,3′-diaminobenzidine via poly(5-aminoisophthalic acid) as a key intermediate. It can also be used as a blended material with polyvinylalcohol to prepare silica-functionalized composite membranes for diffusion dialysis applications. AIPA based metal-organic framework (MOF) can be modified with various functional groups for different applications.