Synthesis and Characterization of Novel Cellulosics
Transcript of Synthesis and Characterization of Novel Cellulosics
Synthesis and Characterization of Novel Cellulosics
Problem statement
Petroleum based polymeric materials• Limited existing quantities of fossil supplies • Escalating cost • Problem of non biodegradability of petroleum based polymers Th t i t ti l ti• The recent environment conservative regulations.
Natural polymers Renewable Renewable Environment friendlyContain many functional groups suitable to chemicalfunctionalization
Cost effective
2
Background
Cellulose is the most abundant renewable biopolymer. Over ~1010 tons are produced per year and only 3% are explored.and only 3% are explored.
‐ Linear homopolymer of D‐anhydroglucopyranoseunits connected by β(1‐4) glycosidic linkages u ts co ected by β( ) g ycos d c ages
Cellulose source DP
Cotton 8000-15000Cellulose
WoodPulpValoniaRayon
8000-9000500-210025000-27000300
‐ Semicrystalline in nature‐ High degree of polymerization (DP)
RayonBagasseAcetobacter xylinum
300700-9002000-6000
3
Cellulose
Cellulose exists in four different polymorphs I (Iα, Iβ), II, III, IV
∆
∆
Hydrogen bonds of cellulose I cellulose II
4
Hydrogen bonds of cellulose I cellulose II
S. Kamel et al. Polymer Letters, 2008, 2, 758–778M. De Souza Lima et al.. Macromolecular Rapid Communication, 2004, 25, 771‐787
Cellulose I and II particle types
Particle TypeParticle size
Length (μm) Width(nm) Crystallinity (%)
Wood fiber &Plant fiber
>2000 20‐50 43‐65
Microcrystalline cellulose
Mi fib il t d
10‐50 10‐50(μm)
0 5 10’ 10 100
80‐85
45 58Microfibrilated
Nanofibrilated Cellulose
0.5‐10’s 10‐100
0.5‐2 4‐20
45‐58
51‐69
Cellulose nanocrystals
Algae cellulose
0.05‐0.5 3‐8
>1 20‐30
54‐88
>80
Bacterial cellulose
Cellulose II
>1 6‐50
Regenerated cellulose
65‐79
27‐43
5
g
R. J. Moon, A. Martini, J. Nairn, J. Simonsen and J. Youngblood, Chem. Soc. Rev., 2011, 40, 3941–3994
Applications of cellulose fiber derivatives
Cellulose esters Cellulose ethers Oxidized cellulose
Films, fibers, explosivescoatings heat
Food additives, fibers, coatings, oil‐well drilling,
Wound dressing, pharmaceuticalcoatings, heat
resistant fabricsg , g,
gelling and foaming , paints, detergents, cosmetics controlled‐
pharmaceutical, skin care
cosmetics, controlledrelease drug tablets
6S. Kalia et al. (eds.), Cellulose Fibers: Bio‐ and Nano‐Polymer Composites, Springer‐Verlag Berlin Heidelberg 2011
Cellulose beads
Important features of bead cellulose•Excellent mechanical stability
Cellulose fiber solutionExcellent mechanical stability •Rigid spherical particles•Narrow particle size distribution•High chemical resistance and compatibility with
Regeneration
Bead cellulose•High chemical resistance and compatibility with most commonly used solvents
•High temperature stability •High selectivity of separation
Bead cellulose
•High selectivity of separation
Application of bead celluloseMetal adsorption Immobilization support ChromatographyChromatography Drug delivery
7D. Zhoua, L. Zhanga and S. Guo, Water Res. 39, 3755 (2005). W. De Oliveira and W. Glasser, J. Appl. Polym. Sci. 60, 63 (1996).V. Weber, I. Linsberger, M. Ettenauer, F. Loth, M. Höyhtyä and D. Falkenhagen, Biomacromolecules 6, 1864 (2005)
Cellulose nanowhiskers (CNWs)
Cellulose nanowhiskers are defined as crystalline rod‐like nanoparticles which are obtained by acid hydrolysis ofnanoparticles which are obtained by acid hydrolysis of cellulose fibers
Plant cell
Microfibril
Acidhydrolysis200nm
8G. Siqueira, J. Bras, A. Dufresne, Biomacromolecules 2009, 10, 425‐432. M. A. S. Azizi Samir, F. Alloin, A. Dufresne, Biomacromolecules 2005, 6, 612‐626. S. Beck‐Candanedo, M. Roman, D. G. Gray, Biomacromolecules 2005, 6, 1048‐1054. M. M. de Souza Lima, R. Borsali, Macromol. Rapid Commun. 2004, 25, 771‐787.
Cellulose nanowhiskers (CNWs)
OO O
OHO
HOOH
OH HO OOO
OH
HOHO
OHOH
H2SO4 /HCl
Acid Hydrolysis
O OHOOH
OOHOOH
OH OH
H2SO42 4
Chracteristics of CNWs
dNano dimensionHigh aspect ratioHigh surface areagHigh mechanical property
9Y. Li, A. Ragauskas, Advance in diverse applications of nanocomposites 2011, pp.17‐36.
Cellulose nanowhiskers
The geometric dimensions depend on the source of the cellulosicmaterial and hydrolysis conditions.
Cotton Ramie Wood Tunicate
L/D=67.0L/D=25.0L/D=11.8 L/D=28.6
Dimensions:Length: 100 – 1000 nm; Diameter: 4 – 50 nm.
10
Habibi, Y.; Goffin, A.‐L.; Schiltz, N.; Duquesne, E.; Dubois, P.; Dufresne, A. J. Mater. Chem. 2008, 18, 5002. Azizi Samir, M. A. S.; Alloin, F.; Paillet, M.; Dufresne, A. Macromolecules 2004, 37, 4313. Roohani, M.; Habibi, Y.; Belgacem, N. M.; Ebrahim, G.; Karimi, A. N.; Dufresne, A. Eur. Polym. J. 2008, 44, 2489.Favier, V.; Canova, G. R.; Cavaille, J. Y.; Chanzy, H.; Dufresne, A.; Gauthier, C. Polym. AdV. Technol. 1995, 6, 351.
Effect of reaction parameters on cellulose nanowhiskers properties
Reaction diti
Length Aspect ti
Sulfur Surface charge d it ( / 2)
Effect of reaction conditions on whisker properties (H2SO4 hydrolysis, softwood pulp)
conditions(reaction time (min), acid/pulp)
(nm) ratio content(%) density (e/nm2)
25, 8.75 141±6 28.2 0.89±0.06 0.33±0.0245, 8.75 120±5 24.5 1.06±0.02 0.38±0.0145 17 5 105±4 23 3 1 26±0 01
Sample Amounts of acidic groups on
45, 17.5 105±4 23.3 1.26±0.01
Sample Amounts of acidic groups on surface (mmol kg‐1)
Strong acid groups
Weak acid groupsgroups groups
H2SO4 84 26
HCl 0 <18TEM images of (a) H2SO4 (b) HCl hydrolyzed whiskers
11J. Araki et. al. Colloids Surfaces A, 1998, 142, 75 – 82. J. Araki et. al. J. wood Sci. 1999, 45, 258 ‐ 261
TEM images of (a) H2SO4 (b) HCl hydrolyzed whiskers
Cellulose nanowhiskers potential areas of application
Nanocomposites Paper & Paperboard Biomedicalp p p
Packaging, AdhesiveElectronic displays Foams
Bioimaging nanodevice drugElectronic displays, Foams
Aerogels, FilmsCoatings / barriers nanodevice, drug
delivery technology, skin care
Arboranano* is a new Canadian Forest NanoProductsNetwork whose objective is to develop high value products from nanocrystalline cellulose.*C d ’ B i l d N t k f C t f E ll FPI ti
12
*Canada’s Business‐led Networks of Centers of Excellence program, FPInnovationsand NanoQuébec.
Typical chemical modification of cellulose
SubstitutionOxidation
Acid hydrolysis
Oxidative cleavage of l l
SubstitutionOxidation
C2‐C3 glycol
Mild reactionHighly selectiveHighly selectiveDAC acts as a reactiveintermediateDialdehyde celluloseCellulose
13
Dialdehyde cellulose(DAC)
Research Studies
To investigate and explore the versatility of cellulose, a renewable resource of raw materials using periodate oxidativerenewable resource of raw materials using periodate oxidative fragmentation synthetic approach
Chemical modification of cellulose through periodate oxidation
Cellulose nanowhiskersCellulose fibers Cellulose beads
14