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Cellulose Micro/Nano fibers (CMNF) from Bioresources in Malaysia Fauziah Abdul Aziz Physics Department Centre For Defence Foundation Studies National Defence University of Malaysia (NDUM) Sg. Besi, Kuala Lumpur. Regional Conference on Solid State Science and Technology
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Cellulose Micro/Nano fibers (CMNF) from Bioresources in MalaysiaFauziah Abdul AzizPhysics DepartmentCentre For Defence Foundation StudiesNational Defence University of Malaysia (NDUM)Sg. Besi, Kuala Lumpur
Regional Conference on Solid State Science and Technology (RCSSST 2014) Copthorne Hotel, Cameron Highlands, Pahang 25 – 27 November 2014
OUTLINE • Introduction • Term CMNF • Why Used CMNF? • Bioresources of CMNF • Some Analysis • Potential Benefits of CMNF • Conclusions
INTRODUCTION • Cellulose is a renewable, biodegradable & the most abundant natural biopolymer in the world • Natural cellulosic fibers are synthesized mainly in plants • cellulose constitutes 40 to 50% of wood
TERM CMNF(Chakraborty et al., 2006) • Microfibres are defined as fibres of cellulose of 0.1-1 µm in diameter • corresponding minimum length of 5-50 µm nanofibrils are at least 1-D at the nanometer scale (1-100 nm)
TERM CMNF (con’t) • While the small fibrils isolated from natural fibers normally have a wide range of diameters, most are below 100 nm & some are above 0.1 µm • A term of cellulose micro/nanofibrils (CMNF) used
Hardwoods-Tropical • dicot angiosperm trees; flowers / seeds ; • broad leaves; evergreen • presence of pores / vessels (obvious) • Gardening plants – shrubs, non-woody • Due to physical structure, hardwood tend to be more expensive than softwood
Some eg of cellulose (whiskers) from different cellulosic sources
Structural Formula of Cellulose, (C5H10O5)n (Cave & Walker, 1994)
Unit Cell of Cellulose Iβ Parallel mode of repeating unit of cellulose Iβ (Nishiyama et al., 2002; Penttilä, 2013) along the a-axis (left, centre chain only) and along the b-axis (right)
Cellulose I • Natural cellulose = native cellulose = cellulose I - ordered • best crystalline allomorph of cellulose • two allomorphs ie • cellulose Iα • cellulose Iβ
Cellulose I (con’t) • The parallel packing of native cellulose make it metastable arrangement • this irregular chain arrangement
Cellulose I (con’t) • the microfibrils, consisting of about • 36 parallel cellulose chains in a crystal are arranged into bundles with outer lateral dimensions in the order of 20 nm
Cellulose Iβ & Cellulose Iα • cellulose Iβ is more disordered of cellulose than cellulose Iα • cellulose Iα is more crystalline than cellulose Iβ • Iβ allomorph is recognized to be dominant in higher plants • higher stability of cellulose Iβ compared to cellulose Iα
WHY USED CMNF? • Renewable materials from nature • Most environmentally friendly materials combined with a biogradable polymer as a matrix • Low abrasion compared to glass-fibre • Non-toxic
WHY USED CMNF? (con’t) • Light • Porous • High mechanical strength
WHY USED CMNF? (con’t) • nonlinear • optical behavior has been the subject of many - design of smart materials
BIORESOURCES OF CMNF • Once upon a time, a living cell of biological origin • Natural sources • Organic • In this work, used plants • Non-Woody • Hardwood
Non-Woody Plants • Banana (Musa acuminata) pseudo-stem • Pineapple (Ananascomosus) leaf
Hardwood • Resak (Vatica spp.) waste • Merbau(Intsiabijuga) waste
Methods & Techniques • chemical treatment • Amorphous region - removed • Purification (lessen DP=no of repeating units per molecule) • Segal’s method • Scherrer equation
DIFFICULTY • producing purely single solid crystal due to its polymorphic behaviour • The increase of defibrillation of cellulose molecule & rearrangement of hydrogen bonds during isolation
STRUCTURAL CHARACTERIZATION • x-ray diffraction (XRD) • field emission scanning electron microscopy (FESEM)
The cellulose residue before dry of alkali treatment process
Cellulose delignification cellulose (DL) of Merbau (Intsia bijuga) After deliglification cellulose (DL) powder
Micrographic of FESEM of after delignification cellulose (DL) of Merbau (Intsia bijuga) Structure and appearance of CMNF by SEM - Regenerated cellulose fiber - nano-scale, Wang et al, 2006
Commercial celluloses, Moran et al, 2008 Product acid-bleached cellulose (BA) of Merbau (Intsia bijuga)
Micrographic of FESEM of acid-bleached cellulose (BA) of Merbau (Intsia bijuga) SEM Microstructure of PP/CMNF composites – overview (Wang et al, 2006)
Structure and appearance of CMNF by SEM, Wang at al, 2006 FESEM images of untreated :R1, M1, P1 & B1
Simulation Diffractogram [XRPD] of microcrystalline states of cellulose (Crowder & Fawcett, ICDD) • Estimates crystallites size parameters • Compute comparable FWHMs for peaks, 3.5nm • Software simulates pattern using d-space & intensity values
Simulation Diffractogram of microcrystalline states of cellulose (Crowder & Fawcett, ICDD)
Diffractogram (XRPD) - Experimental & Standard of Cellulose Iβ Crowder & Fawcett, ICDD
Diffractograms of untreated various CMNF of plants samples Diffractograms of cotton & tunicate cellulose whiskers, Pullawan, 2012
Simulation Diffractogram of microcrystalline states of cellulose (Crowder & Fawcett, ICDD) Diffractograms of treated various CMNF plants sample
CMNF Crystalline cellulose Iα & cellulose Iβ • Presents of cellulose Iα & cellulose Iβ • cellulose Iβ more dorminant than cellulose Iα • Lack of long range order means have no conventional Bragg diffractions • Broad features due to interatomic distances within the disordered structure
XRD of CMNF Pattern • Presents at least more than one phase system • Maxima are shifted from the underlying positions of the major Bragg peaks due to the significant overlap
ICDD Data Base • Best integral index fit is 50-2241, cellulose Iβ
Crystallite size, D (nm) & crystallinity, Xc ( % ) of various CMNF plants samples
Some XRD Results • The percentages of crystallinity of CMNF of all samples increased after passing the chemical treatment • CMNF banana (Musa acuminata) is more crystalline (79.29%) than other CMNF samples
Some Results (con’t) • Significance size reduction in diameter were seen when the fiber was treated during the chemical treatment process