Stabilization effect of lignin in polypropylene and recycled polypropylene

Application of Differential Scanning Calorimetry to the Characterization of Biopolymers

“…On the other side lignin with the important functional groups and the low molecular weight with the narrow polydispersity can be used as the stabilizer for polypropylene (Gregorova et al, 2005a). This section shows that DSC is the sensitive method able to determine the stabilizing effect of lignin in polypropylene.…”

Natural antioxidants as stabilizers for polymers

“…Most of the attempts proved the antioxidant effect of lignin. The antioxidant and stabilizing characteristics of lignin have been studied in several polymers, but mainly in PE [153][154][155][156], PP [153,[157][158][159][160][161][162][163][164], PLA [165,166], poly(3-hydroxybutyrate) (PHB) [167], PCL [168] and in natural rubber [169,170].…”

“…Most other studies also indicated almost invariably that lignin stabilizes polyolefins, unfortunately less attention was paid to the effect of lignin type on stabilization efficiency and to the comparison of its effect to existing stabilizer systems. Gregorová et al [162] proved that lignin increases the thermo- Similarly to lignin, condensed and hydrolysable tannins can be used as polyols for polyurethane synthesis [174,175]. The application of condensed tannins as processing stabilizers is hindered by the same problems as in the case of lignin.…”

The thermo-oxidative stability and flammability of wood/polypropylene composites

“…Due to its structure, lignin has been investigated as antioxidant [47,66]. The high thermal stability of lignin is due to the presence of complex phenylpropanoid units, which consist of aromatic phenyl groups.…”

“…The high thermal stability of lignin is due to the presence of complex phenylpropanoid units, which consist of aromatic phenyl groups. Gregorova et al [66] presented increased antioxidant efficiency when lignin was added into polypropylene. Also, Bettini et al [47] showed that incorporation of lignin in the polypropylene/ coir composites resulted in increase in both the initial thermal decomposition temperatures and oxidation induction time.…”