Characterization of carbonyl chloride-terminated aromatic polyamide nanoparticles with carboxyl groups and their reaction

Aromatic polyamide nanoparticles with carbonyl chloride (COCl) and carboxyl (COOH) groups were obtained using a precipitation polymerization method. The morphology, number of COCl groups incorporated, and degree of polymerization of the resulting particles depended on the reaction system. The COOH group of diamine used decreased the reactivity of NH₂ groups and chemically stabilized the COCl groups existing at the ends of the molecular chains. Also, the COCl groups were retained in particles by the rapid formation of particles. Thus, the chemical structures and formation mechanism were found to play an important role in the formation of particles with COCl groups.