
380 Green Composites from Natural Resources
reinforcement (Thielemans and Wool 2004). The effect of butyrated kraft lignin as
renewable compatibilizer in the composites was assessed instead of traditional com-
patibilizer. The composites were prepared by the vacuum-assisted transfer molding
process with varying amounts of butyrated kraft lignin dissolved in the unsaturated
resin system. It was observed that the butyrated kraft lignin improved the interface
between the resin and reinforcing ax bers, which ultimately enhances the mechani-
cal properties of the composites. For example, the exural strength increased by 40%
for a 5 wt% butyrate