2011 Jornada Científica de la Sociedad Española de Arcillas 14 de ...

Jornada Científica de la Sociedad Española de Arcillas. 14 de Noviembre de 2011
BIONANOCOMPOSITES BASED ON CELLULOSE DERIVATIVES AND
SMECTITES
Y. Koriche* , ** P. Aranda*, M. Darder*, S. Semsari**, E. Ruiz-Hitzky*
* Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco, 28049
Madrid, Spain
** Laboratory of Chemical Engineering, University of Blida, 09000, Blida, Algeria
Bionanocomposites represent an emerging group of advanced materials
resulting from the assembling of different clay minerals and biopolymers [1].
Applications of this type of materials range from their use as green plastics, in
regenerative medicine and as new substrates to immobilize living entities,
sorbents for pollutant removal to the development of novel active phases of ionsensors
of interest in environmental applications [2]. Natural or synthetic clay
minerals (layered silicates such as montmorillonite or fibrous minerals such as
sepiolite and palygorskite) are additives usually incorporated into the
biopolymer matrix. Depending on the geometry and the nature of the nanofiller,
new and improved properties (gas barrier, mechanical stiffness, transparency,
thermal stability...) can be obtained.
In this context, the present work introduces a study on the development and
characteristics of bionanocomposites based on cellulose derivatives,
hydroxypropylmethylcellulose (HPMC) and cellulose acetate (CA), assembled
to two types of smectites, commercial Cloisite®Na and a purified bentonite from
deposits in Maghnia, in the West of Algeria. The chemical composition of this
bentonite is 69.4% SiO 2 , 14.4% Al 2 O 3 , 1.2% MgO, 0.3% CaO, 0.5% Na 2 O,
0.8% K 2 O, 0.2% TiO 2 and 0.05% of As, and its CEC is 80 meq/100 g [3]. One of
the aims of this work is to valorize this natural resource as a potential
component of advanced materials. In a first stage, HPMC was cationized by
treatment with glycidyltrimethylammonium chloride and there after used to
produce its ion-exchange with Cloisite®Na + . Alternatively, CA was mixed with
the bentonite in acetone to produce the bionanocomposite CA/bentonite. The
resulting materials were characterized by using various techniques (FTIR, XRD,
CHN analysis and SEM). XRD characterization of the resulting
bionanocomposites confirms the intercalation of the cationized HPMC between
the layers of Cloisite, as well as the exfoliation of bentonite in the CA matrix.
The affinity of these bionanocomposites towards different heavy metal ions has
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