Preparation and Characterization of Poly (vinyl chloride) Polyblends with Fractionated Lignin

Abstract

Soda lignin was divided into three fractions by sequential extraction with i-propanol/ethanol mixture (4:1v/v) and methanol. Blends of poly (vinyl chloride) (PVC) and lignin were prepared from these lignin fractions. The influences of lignin on the processabilities of the blends, as well as on their mechanical performances and thermal properties, were investigated. The lignin fraction with low molecular weight accelerates the plasticization of blend. It can be dispersed in a rather uniformly form in PVC matrix than any other fractions. The blend prepared from low-molecular-weight lignin fraction exhibits higher mechanical performances than those of blends prepared from any other fractions. The initial decomposition temperature of blends shows a slight decrease, while the incorporation of high-molecular-weight lignin fraction improves the maximum decomposition temperature of blend. The heterogeneity of soda lignin results in the deteriorated mechanical performances of the blend prepared from un-fractionated lignin.

Keywords:

• blend
• fractionation
• lignin
• poly (vinyl chloride)

Acknowledgments

The authors appreciate Hi-Tech Research and Development Program of China (Contract Grant Number: 2007AA100704) and National Basic Research Program of China (Contract Grant Number: 2010cb732206) for financial support.

Notes

^a Mn, number average molecular weight; Mw, weight average molecular weight; D, polydispersity.