Download Hemicelluloses

Designed lignocellulosic-based films
for tunable physico-chemical and
spectral properties
Aguié-Béghin V, Muraille L., Paës G, Chabbert B
COST FP1105 - 8-9 May 2014, Coimbra, Portugal
Objective & Strategy
 Physical , chemical , and cytochemical studies of LC deconstruction and
properties
 Determining and isolating individual features that limit LC deconstruction,
and govern LC properties : role of polymer interactions
•
Designing Lignocellulose-based self-assemblies (films)
Assemblies of plant cell walls which mimic some of the interactions,
composition, physical states found in plant cell wall
Nanostructured LC with variable properties
COST FP1105- Coimbra, Portugal - V. AGUIE-BEGHIN
8-9 May, 2014
Designing bioinspired LC assemblies
Elementary building brick:
40
50 ≤ L ≤ 300 nm
Lmean = 130 ± 5 nm
 ~ 5-6 nm
n= 185
35
Number
30
Cellulose: Cellulose nanocrystals, nanofibrils (CNCs, CNF)
(from ramie, flax, hemp fibers)
25
20
15
10
5
0
Ramie CN
Flax CN
0,05
0,1
0,15
0,2
Length (nm)
0,25
Aspect ratio ~ 30-50
Hemicelluloses: feruloylated arabinoxylans, xylan, glucomannan
H
H
H
Lignin: model lignin (DHP) and lignin from biorefinery
Mw ~3000 g mol-1
Ralph et al., 2007
COST FP1105- Coimbra, Portugal - V. AGUIE-BEGHIN
8-9 May, 2014
0,3
Designing bioinspired Lignocellulose-based films
Nanostructuration of bio-inspired LC assemblies:
Interactions
Non-covalent and covalent
Modulation of polymer interactions (non covalent/ covalent linkages):
- physical blending
- polymerization or cross-linking of phenyl propane units via enzymatic reaction
or chemical oxidation
H
H
H
Hemicellulose
(Xylan or Feruloylated
ArabinoXylan (FAX))
Non cellulosic
polysaccharide- lignin (LCC)
Cellulose Nanocrystals
(CN)
Hemicellulose - CN
H
H
H
H
H
H
H
H
H
Hydrogen-bonds
van der Waals and Hydrophobic
interactions
Ether bonds
Bioinspired assemblies complexity
COST FP1105- Coimbra, Portugal - V. AGUIE-BEGHIN
8-9 May, 2014
Main results
Bioinspired LC model systems
Nanostructuration of LC polymers
chemical properties :
generate bioinspired
systems with enhanced physico-
Modulation of interactions (covalent, non-convalent) between polymers
– Impact on physico-chemical (water sorption and spectral properties),
– Impact on mechanical properties,
– up-grading value of lignin in nanocomposites
Relevant templates which emphasize the relative and quantitative importance of selected
parameters (LC network, protein) on probes mobility:
– Characterization and understanding of probe mobility in lignocelluloses
– Model to predict macromolecular design of efficient lignocellulolytic enzymes
COST FP1105- Coimbra, Portugal - V. AGUIE-BEGHIN
8-9 May, 2014