Preparation and Application of Polyrotaxane Cross-Linking Agent Based on Cyclodextrin in Gel Materials Field

Abstract

The cross-linking point of a conventional chemical cross-linking agent is fixed. Therefore, gels that are prepared with a conventional cross-linking agent have poor deformability, strength, shear resistance, and further properties. Some researchers have prepared a new cross-linking agent using cyclodextrin (CD). In a polyrotaxane cross-linking agent, the cross-linking points can slide freely along the molecule chain. The special “slide ring” structure can provide better elongation, strength, and other properties to gels, which can effectively expand the application of the gel’s materials. This paper summarizes the preparation methods and applications from different types of CD and compares the improvements of properties (swelling, viscoelastic properties, etc.). In addition, the current results of our group are presented, and some ideas are provided for the development of polyrotaxane cross-linking agents.

Facile Preparation of Tough, Puncture-Resistant Antibacterial Polyrotaxane Hydrogel

“…Polyrotaxane (PRX) hydrogel is a novel type of homogeneous hydrogel material that has garnered significant attention in recent years. − Due to the unique topological network structure in which cross-linking rings can slide along the long polymer chain just like “pulleys”, PRX materials would make the internal stress distributed to each chain segment and eventually to the whole network. − Despite the unique “pulley effect” that gives superior elasticity and toughness, difficulty in synthesizing PRX and poor solubility of PRX limit PRX hydrogels’ production and applications. − In addition, there are few cross-linkers developed by cyclodextrin (CD) based hydroxy group on PRX. Among the developed cross-linkers, the choice of cross-linkers is particularly limited due to the bubbles of the gel prepared by cyanuric chloride cross-linking and the N,N-carbonyldiimidazole is sensitive to water …”