两性离子聚合物润滑的研究进展

两性离子聚合物是指高分子链上含有相同数量阴、阳离子的有机高分子材料，其因强亲水性和反聚电解质效应而在润滑方面得到广泛研究. 一方面，两性离子聚合物可通过静电相互作用将润滑体系中的游离水吸附在材料表面，提高其润滑性能；另一方面，两性离子聚合物表面水合程度易受到润滑体系中盐离子类型和浓度影响，改变其润滑行为. 本文中首先介绍摩擦过程中存在的润滑形式，然后总结并分析两性离子聚合物结构及典型两性离子聚合物(例如磺酸根阴离子型两性离子聚合物、磷酸根阴离子型两性离子聚合物和羧酸根阴离子型两性离子聚合物)的润滑行为和机理，最后阐述和展望两性离子聚合物在润滑方面的研究存在的问题和前景. 

Research Progress on Lubrication of Zwitterionic Polymers

Zwitterionic polymers are organic polymers containing the same amount of anions and cations in the molecular chain. Due to their strong hydrophilicity and anti-polyelectrolyte behavior, zwitterionic polymers have been widely studied in the field of lubrication. On the one hand, zwitterionic polymers can adsorb free water from the lubrication system on the surfaces of materials through electrostatic interaction to improve the lubrication performance. On the other hand, the surface hydration degree of zwitterionic polymers is affected by the type and concentration of salt ions in the lubrication system, which can change its lubrication behavior easily. In this paper, the forms of lubrication in the friction process were introduced firstly. Then the structure of zwitterionic polymers and the lubrication behavior and mechanism of typical zwitterionic polymers, such as sulfonate anionic zwitterionic polymers, phosphate anionic zwitterionic polymers and carboxylate anionic zwitterionic polymers, were summarized and analyzed. Finally, the existing problems and prospects of the research on the lubrication of zwitterionic polymers were put forward.