LAUSR

Inspired by the structured architecture of natural materials, research has focused on the assembly of long-range three-dimensional (3D) anisotropic aligned structure through the synergy of silylated binary-composite and bidirectional gradient freezing using renewable and biocompatible cellulose nanofibrils. Low-cost methyltrimethoxysilane (MTMS) was introduced to reinforce the cross-linking strength between nanofibrils, simultaneously improving the surface hydrophobicity of cellulose foams. A copper coldfinger with a thermal insulative polydimethylsiloxane (PDMS) wedge was used to build bidirectional anisotropic aligned porous structures using bitemperature gradients to control the nucleation and propagation of ice crystals. This two-step method successfully assembled the cellulose nanofibrils into ultralight and ultraporous foams. The effects of freezing techniques, including freezer freezing, unidirectional gradient freezing, and bidirectional gradient freezing on the internal morphology and surface str...