Multilayer surface construction for enhancing barrier properties of cellulose-based packaging.

It has been a consistent challenge to develop eco-friendly packaging in its entire life cycle with multiple barriers. Herein, a lignocellulose-derived strategy was developed for enhancing barrier properties of cellulose-based packaging. Porosity and hydrophilicity of paper packaging were remedied by the sequential deposition of oxalic acid modified microfibrillated cellulose (OMFC) and infiltration of nanosized alkaili lignin (NAL). OMFC deposition and NAL infiltration could fill the void among fibers and create hydrophobic micro/nano-roughness on paper surface, which showed synergetic effect on enhancing barrier and mechanical properties by self-bonding and crosslinking between cellulose and lignin. Water vapor transmission rate was reduced by 93 % with initial water contact angle at 113°. Besides, more than four-fold increase in tensile strength along with persisted water and grease resistance were achieved. The result suggests the barrier-enhanced packaging by multilayer surface construction has great potential in bio-based applications considering the biodegradability, biocompatibility, and recyclability.