mz5b00422_si_001.pdf (1.34 MB)
Modulation of Assembly and Dynamics in Colloidal Hydrogels via Ionic Bridge from Cellulose Nanofibrils and Poly(ethylene glycol)
journal contribution
posted on 2015-08-18, 00:00 authored by Jun Yang, Xueming Zhang, Mingguo Ma, Feng XuThe 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.