Advances in synthesis and application of amphoteric polymer-based water treatment agents

Water treatment agents (WTAs) are indispensable in various water treatment processes. Amphoteric polymers possessing unique charge characteristic and diverse polymeric configuration, have emerged as promising material for the development of environmental functional materials, such as membranes, coatings, hydrogels, as well as WTAs. The utilization of amphoteric polymer in the creation of novel and effective WTAs has attracted increasing attention. Understanding the specific properties of amphoteric polymer and the application mechanisms of various WTAs is critical for fabricating high-performance amphoteric polymer-based WTAs. In this work, the synthesis of diverse amphoteric polymer, including betaine-based, amino acid-based and mixed charge polymer, are reviewed. The properties of amphoteric polymer-based WTAs and the influence of environmental and structural factors on their application performance are also discussed. The application of amphoteric polymers in the development and design of various WTAs, including flocculants, adsorbents, antiscalants, catalysts and corrosion inhibitors, are introduced in detail. Furthermore, the prospects of amphoteric polymer in the field of WTA, including novel synthesis methods, thorough understanding on the structure-activity relationship of amphoteric polymer-based WTAs, and their multifunctional application, are elaborated. The applicability of amphoteric polymer-based WTAs can be improved by further exploration on their synthesis, structure-activity relationship and application researches.