Modulation of Assembly and Dynamics in Colloidal Hydrogels via Ionic Bridge from Cellulose Nanofibrils and Poly(ethylene glycol)
journal contributionposted on 18.08.2015 by Jun Yang, Xueming Zhang, Mingguo Ma, Feng Xu
Any type of content formally published in an academic journal, usually following a peer-review process.
The biologically inspired dynamic materials offer principles for designing man-made systems by using assembly approach. In this work, the hybrid hydrogels consist of cellulose nanofibrils (CNFs) that combine a mechanically strong skeleton with flexible PEG chains. The distinct gel state is observed at room temperature with G′ > G″ and an order of magnitude higher G′ values from 0.08 to 0.93 kPa upon increasing CNF concentration from 0.2 to 2 wt % at constant 2 wt % PEG. Combined with mechanically strong CNFs and dynamic ionic bridges through amine-terminated tetra-arm PEG adsorption to TEMPO-oxidized colloidal nanofibrils surface, the assembled colloidal hydrogels show high modulus, reversible gel–sol transition, and rapid self-recovery properties. It is envisioned that simply mixing hard CNF and soft polymeric matrix would lead to a facile method to bridge reversible dynamic bonds in a cellulose-based hybrid network and broad cellulose applications in the preparation of high performance supramolecular systems.