ABSTRACT
Polyampholytes are polymers that carry both positive and negative charges. There are two types of polyampholytes: one in which the existence of positive and negative charges is owing to the presence of anionic and cationic monomers, and one in which the presence of a zwitterion is responsible for both charges. The term polyampholytes refers to a broad array of polymers including both types mentioned above; however, in recent times, zwitterionic polymers in themselves have emerged as a new class of polymers. The main difference between the two types of polyampholytes is that in the former case, the charge of the polymer backbone can be easily changed or tuned by changing the ratio of the two monomers. Thus, in these polymers, one charge can dominate and the net charge of the polymer may be either positive, negative or zero. However, in zwitterionic polyampholytes, the net charge is usually zero under normal conditions because of the presence of an equal number of positive and negative charges. This type of polyampholyte displays a hybrid-like property profile owing to
School of Materials Science, Japan Advanced Institute of Science and Technology 1-1 Asahidai, Nomi, Ishikawa, 923-1292, JAPAN.
