Chiral nematic cellulose nanocrystal (CNC) structural colored materials are the focus of extensive research in recent years on account of their unique helical structure and excellent optical properties. However, the general weak mechanical properties and poor water-resistance of CNC limit its utility. Here, we fabricated highly flexible, water-resistant chiral nematic CNC/Poly(ethylene glycol) diacrylate(PEGDA) composite films, which was realized by co-assembling CNC and PEGDA precursor then via UV curing to construct a three-dimensional crosslinking network. Due to the water stimulus-responsive feature of the CNC and PEGDA, the CNC/PEGDA (8/2) composite film could be used as a water-content detector, photonic paper. In addition, it could produce different crosslinking degrees by coating the PEGMA solution or not, which could be applied to an anti-counterfeit label. The composite film with excellent stability of cycles is expected to be a promising candidate in optical sensors, display, and security fields.

由于其独特的螺旋结构和出色的光学性能，手性向列型纤维素纳米晶体（CNC）结构有色材料是近年来广泛研究的重点。但是，CNC的一般较弱的机械性能和较差的防水性限制了其实用性。在这里，我们制造了高度柔性的，耐水的手性向列型CNC /聚乙二醇（二甘醇）二丙烯酸酯（PEGDA）复合膜，这是通过将CNC和PEGDA前体共组装然后通过UV固化来构建三维交联网络而实现的。由于CNC和PEGDA的水刺激响应特性，CNC / PEGDA（8/2）复合膜可用作含水量检测器，光子纸。此外，通过涂覆或不涂覆PEGMA溶液，它都可能产生不同的交联度，可以应用于防伪标签。具有优异循环稳定性的复合膜有望在光学传感器，显示器和安全领域成为有前途的候选材料。