The development of reversible deactivation radical polymerization (RDRP) opened a vast number of possibilities for the synthesis of exotic macromolecular architectures with tailored properties for diverse applications. Given the advantages that RDRP provides, it is possible to obtain such architectures with good control over molecular weight distribution, morphology, composition, and functionality. A field of great interest for many research groups is the modification of natural polymers (or polysaccharides) with synthetic polymers via polymer grafting using RDRP approaches, such as atom transfer radical polymerization (ATRP), nitroxide-mediated polymerization (NMP), and reversible addition–fragmentation chain transfer polymerization (RAFT) since the properties of the resulting materials can be tailored. Two polysaccharides that stand out due to their properties and potential applications after polymer modification are chitosan and cellulose nanocrystals (CNC). Chitosan is a derivative of chitin, desirable for its biocompatibility, degradability, low toxicity, and ability to act as a chelating agent with potential applications in the biomedical and pharmacy fields or wastewater treatment. CNC are well known for their outstanding mechanical properties, such as high specific strength and modulus and high surface area. For both chitosan and CNC, however, their hydrophilic nature makes them incompatible with non-polar systems, limiting their potential applications. This feature article highlights the most recent development and our personal perspective of polymer grafting techniques on CNC and chitosan via RDRP for the design of different architectures, the design of responsive materials from such polysaccharides, potential water treatment applications, and our opinion of the future of this attractive research field.

中文翻译：

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壳聚糖和纤维素纳米晶可控聚合物改性的观点：迈向功能材料的设计

可逆失活自由基聚合（RDRP）的发展为合成具有适合各种应用的定制特性的奇异大分子结构开辟了大量可能性。鉴于 RDRP 提供的优势，可以获得对分子量分布、形态、组成和功能有良好控制的此类架构。许多研究小组非常感兴趣的领域是使用 RDRP 方法通过聚合物接枝对天然聚合物（或多糖）进行改性，例如原子转移自由基聚合 (ATRP)、氮氧介导聚合 (NMP) 和可逆加成– 断裂链转移聚合 (RAFT)，因为可以定制所得材料的特性。由于聚合物改性后的特性和潜在应用而脱颖而出的两种多糖是壳聚糖和纤维素纳米晶体 (CNC)。壳聚糖是甲壳素的衍生物，因其生物相容性、可降解性、低毒性以及作为螯合剂的能力而备受青睐，在生物医学和制药领域或废水处理中具有潜在应用。CNC 以其出色的机械性能而闻名，例如高比强度和模量以及高表面积。然而，对于壳聚糖和 CNC，它们的亲水性使它们与非极性系统不相容，限制了它们的潜在应用。