中文摘要：

水凝胶是一种交联高分子材料,在药物传输、传感器技术、组织工程中发挥重要作用。通过高效率和高精确度的点击反应合成水凝胶,具有快速、模块化以及副反应少等优点,并且能够得到近乎理想的网络结构。Cu（Ⅰ）催化的叠氮-炔之间的环加成（CuAAC）反应作为点击反应的典型代表,已广泛应用于水凝胶的制备。但由于该反应在制备水凝胶的过程中使用了Cu（Ⅰ）催化剂,导致产品易被金属铜盐污染,从而使该反应在其制备领域受到限制。基于此,无铜点击反应,如巯基-烯/炔反应、呋喃/蒽-马来酰亚胺（MI）修饰的Diels-Alder环加成（D-A）反应以及环张力促进的叠氮-炔环加成反应（SPAAC）已经被应用到水凝胶的制备以及功能化方面。本文就近年来上述无铜点击反应在水凝胶合成及功能化方面的应用进行综述,并对其发展趋势进行展望。

英文摘要：

Hydrogels are a class of hydrophilic, crosslinked polymeric materials. They are valuable tor drug delivery, biosensing and tissue engineering. Generally, hydrogels with nearly ideal network structures can be obtained via the click reactions which have advantages of fast reaction rate, modularity and less by-products. As the representative of click chemistry, Cu（ [ ）-catalyzed azide-alkyne cycloaddition （CuAAC） reaction has been applied widely for the preparation of hydrogel materials. The copper metal contamination in the obtained hydrogels is a major concern because of the use of copper salts catalytic system. The drawback counteracts the applications of CuAAC reaction in the fields of synthesis of hydrogels. Copper-free click reactions, such as thiol- ene/yne reaction, furan/anthracene-maleimide （MI） Diels-Alder （D-A） reaction and strain-promoted alkyne- azide cycloaddition （SPAAC） reaction, have been widely used to prepare hydrogel materials. In this paper, the application of the copper-free click reaction in preparing the In addition, the trend of their development is discussed. hydrogels and their functionalization are reviewed