Poly(Lactic Acid) Blended with Cellulolytic Enzyme Lignin: Mechanical and Thermal Properties and Morphology Evaluation

Potential of Lignins as Antioxidant Additive in Active Biodegradable Packaging Materials

“…The relatively low decrease of yield stress and strain at break were certainly due to the counterbalance of two effects: the addition of high molecular mass lignin lead to increase of yield strength and decrease of strain at break, while the plasticization of PLA by low molecular mass lignin lead to decrease of yield strength and increase of strain at break. The effect of lignin on the mechanical properties data was also consistent with Ouyang et al [46] who observed a decrease in the maximum strength for the blend of PLA/cellulolytic enzyme lignin and a slight decrease of strain at break. Comparable behaviour was also observed for PLA/Vanillex HW lignin samples [47].…”

“…In conclusion, the blending of PLA with lignin did not worsen the good mechanical performance of the materials. This pointed to compatibility between lignin and PLA, a result also pointed out by Ouyang et al [46] and Li et al [47]. This compatibility might be optimized in choosing proper lignin grades, following the suggestion of Pouteau et al [26].…”

“…The inclusion of natural antioxidants in PLA in the aim of developing an active material has already been suggested in literature [43][44][45]. Furthermore, some studies already exist pointing to the feasibility of inclusion of lignin into PLA [5,9,46,47]. Two commercial alkali lignins were chosen because of their expected radical scavenging activity and their difference in the free phenolic monomers content.…”

Competitive Interactions in Aromatic Polymer/Lignosulfonate Blends

“…The importance of hydrogen bonds was pointed out in several publications by a number of authors. They were thought to be significant in poly(vinyl chloride) [31,33], poly(vinyl alcohol) [34,35], poly(lactic acid) [37][38][39], and polyhydroxybutyrate [42,43]. In spite of the importance of hydrogens bonds, Doherty et al [54] claimed that they alone are not sufficient to compete successfully with the strong interactions among lignin molecules and to result in complete miscibility.…”

“…A considerable number of papers have been published on the blends of lignin with a wide range of polymers including proteins [10][11][12], starch [13][14][15], polyolefins [16][17][18][19][20][21][22][23][24][25][26], vinyl polymers 4 [18,19,21,[27][28][29][30][31][32][33][34][35] and polyesters [19,21,22,[36][37][38][39][40][41][42][43]. The chemical modification of lignin [10,14,16,[20][21][22]27,29,36,40,…”