M. Kazayawoko et al., X-RAY PHOTOELECTRON-SPECTROSCOPY OF LIGNOCELLULOSIC MATERIALS TREATEDWITH MALEATED POLYPROPYLENES, Journal of wood chemistry and technology, 18(1), 1998, pp. 1-26
The esterification reaction between lignocellulosic materials (ALCELL
lignin and Bleached kraft cellulose) and maleated polypropylenes (graf
t copolymerization of maleic anhydride into polypropylene chains) was
investigated. The reaction was conducted in a reactor in the presence
of xylene used as a solvent and sodium hypophosphite as a catalyst. Th
e reaction between lignocellulosic materials and pure maleic anhydride
was also conducted to determine the effect of the long polypropylene
chains on the formation of ester bonds. The XPS studies of maleated bl
eached kraft cellulose showed the emergence of C4 carbon type on high
resolution spectra, which was related to ester carbonyl functionality
formed by esterification reaction. No evidence of esterification was o
bserved between ALCELL lignin and maleated polypropylenes. The XPS stu
dies demonstrated that both ALCELL lignin and bleached kraft cellulose
chemically react with maleic anhydride with the formation of ester bo
nds.