Water of functionalized microfibrillated cellulose as foaming agent for the elaboration of poly(lactic acid) biocomposites
This article presents a study on the foam processing of sustainable biocomposites made of polyl(actic acid) (PLA) and functionalized microfibrillated cellulose (MFC) using water as a foaming agent. MFC contains moisture and can be used as a water carrying agent in a 'green' foaming process. The quantity of water, that is, of foaming agent, was adjusted by chemically modifying the fibrils, changing their surface hydroxyl groups, and thus tailoring their hygroscopicity. Functionalized carboxymethylated and acetylated MFC were processed with PLA in a two-step microextruder and various foams were produced. The thermal behavior of the MFC was fully investigated to determine the amount of available foaming agent. Densities and morphologies of resulting foams were correlated to processing temperatures and to water contents ranging from 3.7 to 98 wt%. A low processing temperature and MFC water content of 9 wt% provided uniform foams with the lowest densities. However, too high water content showed poor foaming efficiency and high densities. The obtained foams were compared with foam processed with a chemical foaming agent, used alone or in combination with the MFC.
WOS:000292998700006
2011
30
8
709
719
[Boissard, Carole I. R.; Bourban, Pierre-Etienne; Manson, Jan-Anders E.] Ecole Polytech Fed Lausanne, Lab Technol Composites & Polymeres, CH-1015 Lausanne, Switzerland. Manson, JAE (reprint author), Ecole Polytech Fed Lausanne, Lab Technol Composites & Polymeres, Stn 12, CH-1015 Lausanne, Switzerland jan-anders.manson@epfl.ch
ISI Document Delivery No.: 795TM
Cited Reference Count: 52
Boissard, Carole I. R. Bourban, Pierre-Etienne Tingaut, Philippe Zimmermann, Tanja Manson, Jan-Anders E.
European Commission
This study was supported by the European Commission under the FP7 project SUSTAINCOMP.
Sage publications ltd
London
REVIEWED