A new platform of functional hybrid materials from anionically charged high-aspect-ratio cellulose nanofibrils (CNFs) and a dendritic polyampholyte, Helux, is herein proposed. The polyampholytic character of Helux enabled facile and efficient nanoscale mixing with the CNFs, and the resulting composite mixtures of CNFs and Helux displayed thixotropic behavior and formed physical and reversibly cross-linked gels when left unperturbed for short spans of time. The gel could be chemically cross-linked into self-supporting solid hydrogels containing impressive water contents of 99.6% and a storage modulus of 1.8 kPa by thermal activation. Non-cross-linked mixtures of CNF/Helux were assembled into composites, such as films by solvent casting and aerogels with densities as low as 4 kg/m³ by lyophilizing ice-templated CNF/Helux mixtures. The resulting materials exhibited excellent wet stability due to the heat-activated cross-linking and were readily available for postfunctionalization via amidation chemistry using Helux-accessible amines in aqueous conditions. The mechanical performance of the films was not jeopardized by the addition of Helux. Additionally, by varying the amount of Helux, the compressive elastic modulus of aerogels was tunable in both the non-cross-linked and cross-linked states. The fast and efficient nanoscale mixing of anionic CNFs and a polymer containing cationic groups is unique, novel, and promising as a functional material platform. Sustainable CNFs guided by heterofunctional dendritic polyampholytes are envisaged to act as a pillar toward high-performance applications, including biomedicine and biomaterials.

中文翻译：

---

功能性纤维素纳米原纤维材料的树突状多两性离子辅助形成。

本文提出了一种新的功能性杂化材料平台，该平台由阴离子带电的高纵横比纤维素纳米原纤维（CNF）和树状多两性电解质Helux组成。Helux的多水解特性使其能够与CNF轻松高效地进行纳米级混合，并且当CNF和Helux短时间不受干扰时，所得的CNF和Helux复合混合物显示出触变性，并形成了物理的和可逆的交联凝胶。可以通过热活化将该凝胶化学交联成自支撑固体水凝胶，该凝胶包含令人印象深刻的99.9％的水含量和1.8 kPa的储能模量。CNF / Helux的非交联混合物通过溶剂流延和密度低至4 kg / m ^3的气凝胶组装成复合材料，例如薄膜通过冻干以冰为模板的CNF / Helux混合物。所得的材料由于热活化的交联而表现出优异的湿稳定性，并且易于在水性条件下通过使用可通过Helux接触的胺进行酰胺化化学反应而用于后官能化。薄膜的机械性能不会因添加Helux而受到损害。另外，通过改变Helux的量，气凝胶的压缩弹性模量在非交联和交联状态下均可调。阴离子CNF和含有阳离子基团的聚合物的快速，高效的纳米级混合是独特，新颖且有望用作功能材料的平台。设想了由杂官能树突状两性电解质引导的可持续CNF，可作为高性能应用的支柱，