Air-dried porous powder of polymethyl methacrylate modified cellulose nanocrystal nanocomposite and its diverse applications

Owing to the advantages in storage, transportation and melt-processing, the powder form of cellulose nano crystals (CNCs) as an attractive biomass filler is highly desired for the industrial application. Herein, by systematically tailoring the reaction conditions, we prepared the air-dried porous powder of CNCs modified with PMMA (CNCs-g-PMMA) via a green synthesis route, that is, using ceric ammonium nitrate (CAN) as an initiator in aqueous medium. Our results show that the porous powder of air-dried CNCs-g-PMMA can be easily obtained when the grafting ratio of PMMA was higher than 70 wt%. CNCs-g-PMMA porous powder demonstrates high specific surface area (47.8 m(2)/g), excellent hydrophobicity and oleophilicity properties. It therefore can be used as a filter for oil/water separation or as a highly efficient absorbing material. Moreover, benefiting from the improved thermal stability of CNCs and melt-processing character of PMMA, the porous powder of CNCs-g-PMMA has been converted to a transparent film by a simple compression molding. The as-prepared film demonstrates extraordinary UV shielding and mechanical stability upon heating. Particularly, there is an extraordinary increase in glass transition temperature of PMMA from 112.6 to 138.6 degrees C. This research provides a facile and green strategy to fabricate CNCs-g-PMMA porous powder, which shows industrial applications from different perspectives.