Dicarboxylate nanocrystalline cellulose (DCNC) polyelectrolytes were prepared from nanocrystalline cellulose (NCC) by introducing carboxylate units at the C-2 and C-3 positions of a glucose moiety through a two-step selective oxidation process. The polyelectrolyte nature of the DCNC was investigated by measuring the water uptake capacity with a customized ion exchange system. The equilibrium water uptake capacity of DCNC was almost ten times greater than that of conventional C-6 functionalized monocarboxylated NCC. The conversion of NCC to DCNC ensured the presence of a large number of dissociable electrolytic ions and high degrees of conformational freedom in the material to generate high osmotic pressure. Conductivity and dynamic light-scattering measurements were performed to relate the water uptake capacity with the chemical and structural changes of the polyelectrolytes. Furthermore, it was observed that the ionic strength of the solution played a critical role in controlling the water uptake capacity of the material.

通过两步选择性氧化过程，通过在葡萄糖部分的C-2和C-3位置引入羧酸酯单元，从纳米晶体纤维素（NCC）制备二羧酸盐纳米晶体纤维素（DCNC）聚电解质。通过使用定制的离子交换系统测量吸水能力，研究了DCNC的聚电解质性质。DCNC的平衡吸水能力几乎是常规C-6官能化的单羧化NCC的十倍。NCC向DCNC的转化确保了材料中大量可分解的电解离子的存在和高构象自由度，从而产生高渗透压。进行了电导率和动态光散射测量，以将吸水能力与聚电解质的化学和结构变化相关联。此外，观察到溶液的离子强度在控制材料的吸水能力中起关键作用。