Studies on polymers and composites from lignin and fiber derived from sugar cane

Sugarcane fiber (i.e. bagasse) lignin has a larger fraction of aromatics unsubstitution in the ortho position than hardwood or softwood lignin and hence has the greater ability to be derivatized. Furthermore, organosolv lignin has a higher purity than sulfonated and kraft lignins. This work examines the purification of organosolv lignin derived from bagasse and the physico-chemical properties of the lignin and lignin-phenol formaldehyde (PF) resin coatings, and composites. The wetability tests have shown that lignin and lignin-PF resin films are effective water barrier coatings, though the contact angles of lignin-PF resin films were considerably less than the wax films. The overall mechanical properties (i.e. peak stress, peak strain and modulus) of the bagasse fiber composites were lower than the values obtained with the composites without the inclusion of bagasse fiber. Copyright (C) 2007 John Wiley & Sons, Ltd.