纳米纤维素-聚吡咯/天然橡胶柔性导电弹性体的制备与性能

以纤维素纳米纤丝（Cellulose nanofibrils，CNFs）为生物模板，将聚吡咯（Polypyrrole，PPy）原位聚合在CNFs表面，再将CNF-PPy复合物均匀分散到天然橡胶（Natural rubber，NR）弹性基体中，制备了具有高柔韧性的纳米纤维素-聚吡咯/天然橡胶（CNF-PPy/NR）导电弹性体。结果表明：CNFs可协助PPy在NR基体中形成三维导电网络结构，并提高弹性体的力学性能和导电性能，有效降低其逾渗阈值。当添加质量比为5%（以橡胶质量为基准，下同）的CNF和20%的PPy时，CNF-PPy/NR的拉伸强度可达（8.97±0.92）MPa，分别约为PPy/NR及纯NR的1.56倍和9.54倍，电导率可达（0.134±0.063）S/m；在0.3 A/g的电流密度下，比电容可达96 F/g，并在1.0 A/g电流密度下循环充放电1 200次后，比电容仍可保持其初始值的72%。此导电弹性体具有良好的力学强度和电学性能，有望应用于柔性有机电子器件领域。

Preparation and characterization of cellulose nanofibers-polypyrrole/natural rubber flexible conductive elastomer

Polypyrrole (PPy) was in-situ polymerized on the surface of biological template-cellulose nanofibers (CNFs) to form the CNF-PPy complexes, which further were uniformly dispersed into natural rubber (NR) elastomeric matrix to prepare CNF-PPy/NR conductive elastomers with high flexibility. The results show that CNFs can assist PPy to form a three-dimensional network structure in NR matrix, improve the mechanical properties and electrical conductivity of elastomers, and reduce the percolation threshold effectively. When adding 5% CNF(rubber mass as 100) and 20%PPy, the tensile strength of CNF-PPy/NR is (8.97±0.92) MPa, which is about 1.56 times of PPy/NR and 9.54 times of pure NR, respectively, and the conductivity is up to (0.134±0.063) S/m; At 0.3 A/g current density, the specific capacitance can reach 96 F/g, and it can still maintain its initial value of 72% in the cycle of charge and discharge 1 200 times with 1.0 A/g current density. The conductive elastomer exhibits good mechanical and electrical properties, which is expected to be applied in the field of flexible organic electronic devices.