Surface characterization by XPS, contact angle measurements and ToF-SIMS of cellulose fibers partially esterified with fatty acids

authors	Freire, CSR; Silvestre, AJD; Neto, CP; Gandini, A; Fardim, P; Holmbom, B
nationality	International
journal	JOURNAL OF COLLOID AND INTERFACE SCIENCE
author keywords	cellulose fibers; fatty acids; surface and in-depth esterification; surface characterization; XPS; contact angle; ToF-SIMS
keywords	RAY PHOTOELECTRON-SPECTROSCOPY; MECHANICAL PULP FINES; FTIR; ECF
abstract	The topochemistry of the controlled heterogeneous esterification of cellulose fibers with fatty acid chlorides of different chain length, both in swelling and non-swelling media, was assessed by X-ray Photoelectron Spectroscopy (XPS), Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) and contact angle measurements. On the one hand, the results provided by the combined use of these three powerful techniques showed unambiguously the occurrence of the reaction at the fibers' surface and, on the other hand, the XPS results showed that the surface coverage with the fatty acid moieties increased with their chain length, but was only modestly affected by the degree of substitution (DS), suggesting that when the esterification yield was increased (higher DS values), an in-depth reaction also occurred, particularly when DMF was used as a cellulose swelling medium, involving the OH groups buried below the fibers' surface. (c) 2006 Elsevier Inc. All rights reserved.
publisher	ACADEMIC PRESS INC ELSEVIER SCIENCE
issn	0021-9797
year published	2006
volume	301
issue	1
beginning page	205
ending page	209
digital object identifier (doi)	10.1016/j.jcis.2006.04.074
web of science category	Chemistry, Physical
subject category	Chemistry
unique article identifier	WOS:000239538300024