Blends of vinylic copolymer with plasticized lignin: Thermal and mechanical properties

The article presents an investigation into the use of plasticizers for redu cing the degree of association existing within lignin molecules, in order t o overcome adverse effects on the mechanical properties of its blends with a vinyl chloride-vinyl acetate (VC-VAc) copolymer. Infrared spectroscopy an d differential scanning calorimetry were performed to examine the effect of the plasticizer type and concentration in plasticizing Alcell, an organoso lv lignin. The results show that the compatibility and efficiency of a plas ticizer are strongly influenced by the solubility parameter, which should b e close to that of the lignin. Polyblends prepared with several plasticizer s, Alcell lignin, and the VC-VAc copolymer were also investigated by therma l analysis and mechanical testing. Variations in the mechanical properties of these blends were found to correlate with the lignin dispersion quality and with the plasticizer efficiency in Alcell lignin. (C) 2001 John Wiley & Sons, Inc.