Oven‐Drying Microfibrillated Cellulose Covered with a Low Molecular Weight Copolymer for Dispersion in a Polymer Matrix

Abstract

AbstractHornification remains a great challenge to the large‐scale use of oven‐dried microfibrillated cellulose (MFC) in industrial processes due to the difficulty to redisperse the oven‐dried MFC, especially in non‐polar polymer matrices. Therefore, an MFC coverage treatment with a low molecular weight copolymer is proposed here as a method to overcome hornification. MFC‐copolymer is produced by mechanical stirring and then oven‐dried. A poly(lactic acid) (PLA)/poly(ε‐caprolactone) (PCL)/MFC‐copolymer blend is prepared by melt extrusion to assess the dispersiveness of the treated MFC into the polymer matrix. Fourier Transform Infrared (FTIR) results suggest that the copolymer terminal hydroxyls can interact with the reactive hydroxyls present on the MFC surface, decreasing MFC hydrophilicity. Scanning Electron Microscopy (SEM) confirms that the copolymer covers parts of the MFC surface, which enables the microfibrils' redispersion. The solvent‐free, eco‐friendly, and low‐cost MFC‐copolymer treatment facilitates MFC redispersion by melting extrusion process in a low polarity polymeric matrix.