Surface esterification of cellulose fibers: characterization by DRIFT and contact angle measurements.
The surface chemical modification of microcrystalline cellulose and cellulose fibers obtained from different sugar cane bagasse pulping processes, viz. Kraft, organosolv ethanol/water and organosolv/supercritical carbon dioxide, were studied in heterogeneous conditions using modest amounts of octadecanoyl and dodecanoyl chloride. The ensuing surfaces acquired a non-polar character, suitable for incorporating these fibers as reinforcing agents in composite materials based on polymeric matrices. The success of these chemical modifications was assessed by diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy, elemental analysis, scanning electron microscopy (SEM) and contact angle measurements. In particular, the dynamic and equilibrium contact angle measurements, before and after the treatments, revealed that the value of the polar component (gamma(s)p) of the surface energy had decreased very considerably following the modification.
Pasquini
Daniel
D
Instituto de Química de São Carlos, Universidade de São Paulo, C.P. 780, 13560-970 São Carlos, S.P., Brazil.
Belgacem
Mohamed Naceur
MN
Gandini
Alessandro
A
Curvelo
Antonio Aprigio da Silva
AA
D002482:Cellulose / Q000031:analogs & derivatives* / Q000737:chemistry* / Q000648:ultrastructure; D004951:Esterification; D008855:Microscopy, Electron, Scanning; D012542:Scattering, Radiation; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D014965:X-Rays
C020253:cellulose ester plastic; D002482:Cellulose