Materials and methods
PLA-based polymer, PLA Ingeos Byopolymer 3251D supplied by Nature Works, was used as a biodegradable thermoplastic matrix. Kraft bleached fibers derived from softwood (Pinus radiata), prepared by Celulosa Arauco y ConstituckSn (Chile) and supplied by Torraspapel S.A. (Spain) were used as lignocellulosic reinforcement.
Bis(2-methoxyethyl) ether (diglyme), with a 134.17 g/mol molecular weight, and a 162°C boiling point, provided by Clariant, was used as a dispersing agent during the composite compounding
X-ray photoelectron spectroscopy analysis of fibers
The analysis was carried out using a Kratos Axis Ultra DLD instrument. Survey scans were collected between 1200 to 0 eV of binding energy, at 1 eV of resolution, using a monochromatic aluminum source. In addition, high resolution scans were collected over the C1s and O1s peaks at 0.05 eV of resolution. The survey scans were quantified using CASA software and the high resolution scans curve fitted.