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College of Agricultural SciencesCampus of Botucatu
BrazilCoordinatorCoordinator: Prof. Alcides Lopes Leão: Prof. Alcides Lopes Leão
EE--mail: mail: [email protected]@fca.unesp.br
55(14)381155(14)3811--7257 7257 -- BRAZILBRAZIL
POLYMER NANOCOMPOSITES WITH NANOWHISKERS ISOLATED FROM COIR
FIBRES
Alcides L. Leão & Sivoney F. SouzaUNESP - São Paulo State University, Botucatu, BrazilBibin Mathew Cherian – Mahatma Gandhi University,
India
.
unesp - Sao Paulo State University• Students: - Undergraduate: 34,425 (5,800/yr.)
- Graduate: 12,031 (2,000/yr)• Professors: 3,350 (more than 85% work full time in teaching,
research and extension services)• Staff: 6,984• Campuses: 23 in 21 cities• Laboratories: 1,900• Libraries: 30• Area Total: 62 million m2
• Area of Construction: 733,000 m2
• Budget 2008: USD 650 millions• Graduate Programs: 174 graduate courses at MSc. and PhD. levels
divided into 101 Master and 73 Doctorate courses• Undergraduate Programs: 168 undergraduate programs at
bachelor's level in nearly every knowledge areas and prepares students for 63 careers
4
Processes Utilized in Composites at UNESP - Botucatu
• Extrusion (profiles and pellets) – macro, micro and nano • Injection molding• Thermoforming• BMC (partnership with private companies)• SMC (partnership with private companies)• RTM (partnership with private companies)• LFRT – Long Fiber Reinforced Thermoplastics (profiles
and railroad crossties)
Plastic Products and Environment
Plastic packaging materials is a big environment issue (world production is ca. 50 millton/ year and the market is ca.100 mill USDPackaging products constitutes ca 50% of total plastic usage
Rigid PackagingBuilding
Automotive
HpuseholdAppliances
Electrical
Wire & CableFibre
Others
Flexible Packaging
Importance of Natural Fibers
Cost effective
Renewable
Eco-friendly
Thermal insulators
Nonabrasive to processing equipment
Under utilized
Social responsible
Engineering Materials (Repetitive, Homogenous, Predictable)
Engineering Materials
Classics Non-classics
Wood GlassCeramics Metals Man-made Polymers
Classificação dos materiais de engenharia (MANO, 2000)
Biowaste
Collection
COMPOST
BiologicalDegradation
RENEWABLE RAW MATERIALS
Photosynthesis
HarvestingExtraction
10 to 20 tons dry mass /ha annualy
Strach Celluloses, Agrochemicals, hemicelluloses, biopolimer
Processing
INTERMEDIATESConversion
Materials Cycle
endothermic (capturing) 2,86 kJ/mol of glucose formed
PRODUCTSTextiles, composites, agrochemicals, energy
–
340 l ethanol/1ton straw
CO2
H2
O10 ton Biomass collecting 2,5 ton CO2
CLASSIFICATION OF NATURAL FIBRESNATURAL FIBRES
PLANT ANIMAL
BAST LEAF SEEDS FRUIT GRASS
Flax(Linum Usitatissimum)
Hemp(Cannabis Sativa)
Kenaf(Hibiscus Cannabinus)
Jute(Corchorus Capsularis)
Ramie(Boechmeria Nivea)
Isora(Helicteres Isora)
Ananas(Ananas Bracteatus)
Sisal(Agave Sisalana)
Abaca(Musa Textilis Nee)
Curaua(Ananas Erectifolius)
Cabuya(Furcraea Andina)
Palm
Opuntia(Opuntia Galapagos)
Paja(Carludovica Palmata)
Jukka(Yucca L)
African Palm
Chambira(Astrocaryum Chambira)
Cotton(Gossypium)
Coir(Cocos Nucifera)
Kapok(Ceiba Pentandra)
Soya(Glycine)
Poplar(Populus Tremula)
Calotropis(Calotropis Procera)
Coir(Cocos Nucifera)
Luffa(Luffa Aegyptiaca)
Bamboo(Bambusa Shreb.)
Totora(ScirpusCalifornicus)
WOOLS AND HAIR
SILK
Sheep(Ovis Aries)
Alpaca(Lama Pacos)
Camel(CamelusBactrianus)
Natural(Bombyx Mori L)
Spider Silk(Araneus Diadematus)
Goat(Genus Capra)
Horse(Equus Caballus)
Rabbit(OryctolagusCuniculus)
Vicuna(Lama Vicugna)
MINERAL
Asbestos
Glass
Mineral Wool
Basalt
Ceramic
Aluminium
Borate
Silicate
Carbon
WOOD
hardwood
softwood
10
Natural Fibers in South America Brazil is the biggest producer and consumer
• Abaca – Ecuador• Fique – Colombia, Ecuador• Totora – Ecuador, Peru and
Bolivia• Flax – Argentina (?)• Embira – Brazil• Caroá – Brazil• Bamboo - Brazil• Phormium (imbira) - Brazil• Curaua – Brazil, Venezuela• Kurowa (curaua) - Guiana• Sugar cane bagasse – Brazil,
Cuba and Colombia,• Pineapple (Brazil)
• Sisal – Brazil, Cuba, Haiti México
• Buriti, Carnauba, Buriti, and Tucum – NE of Brazil (native palm trees
• Malva & Jute – Brazil• Coir – Brazil• Banana – Brazil• Hemp – Chile• Taboa (Typha) - Brazil• Piteira – Brazil and Ecuador• Tagua – Ecuador• Jarina – Brazil (Vegetable ivory)• Piaçava – Bahia, Brazil
Totora – Huros at Lake Titicaca
Arrangement of Fibrils, Microfibrils and Cellulose in the Cell Walls
Components Arrangement
Arrangement of Cellulose, Hemicellulose and Lignin in cell wall
Fibers CompostionItem Taboa Curaua Pineapple Banana Coir
ExtractivesHot Water (%)
8.5 5.5 6.0 10.6 6.4
Lignin Klason(%)
16.4 11.1 10.5 18.4 32.8
Holocellulose(%)
71.3 81.2 80.5 68.6 58.4
Cellulose(%)
35.0 70.4 73.4 64.2 44.2
Ashes(%)
3.8 2.2 3.0 2.4 2.4
16
Advantages of Cellulose NanofibersRenewableBio-basedLow densityGood Surface appearanceReduced smoke emission.
Decreased permeability to gases, water and hydrocarbons.
Optical transparency
Nanofiber Scale
Nanocomposites
Bio based polymers and nano reinforcements
Improve the polymer properties:
Thermal stabilityMechanicalToughnessBarrierExpect that these materials
can be used in packaging, medical, automotive and textile
Why Bio-nanocomposites ?Nanocomposites from renewable rawmaterials for automotives Biodegradable films for packaging applications (barrier layers)Biodegradable packaging materialsMedical devices compatible with the human body
Bio-nanocomposites
Toyota
Bio based nanoreinforcements in biopolymers
Improve biopolymer properties:−
Thermal stability
−
Mechanical−
Toughness
−
Barrier
Expect that these materials can be used in packaging, medical, automotive and textile applications
Nanoparticles vs. Microparticles
Big variation of properties inherent to the natural products (climatic conditions, maturity, type of soil,...)
The basic idea to achieve further improved fiber and composite is to eliminate the macroscopic flaws by disintegrating the natural grown fibers, and separating the almost defect free highly crystalline fibrils
Increase of the specific area (~100 m2.g-1 vs. ~1 m2.g-1)The average inter-particles distance decreases as their size
decreasesParticle-particle interactions
Improved properties for low filler content without detrimental effect on impact resistance and plastic deformation
Reduction of gas diffusion (barrier effect)
Because these microfibrils contain only a small number of defects, their axial Young's modulus is close to the one derivedfrom theoretical chemistry and potentially stronger than steel and similar to Kevlar
100 nm 5 µm
Native cellulose consists of hierarchical structure (built up by smaller and mechanically stronger entities-
cellulose
fibrils)
Fibrils = crystalline + noncrystalline domains (surface + along the main axis)
Noncrystalline domains form weak spots along the fibrils
Cellulosic Nanoparticles
CELLULOSE FIBERS STRUCTURAL ENGINEERING
Source of Cellulose Fibers
Coir
Cellulose Microfibrills and Whiskers
• Wood fiber, diam 20-30 μm, length 2-5 mm• Microfibrills, diam <30 nm, length > μm• Whiskers, diam 3-10 nm, length < 300 nm• Mechanical properties increases when size
decreases• Fiber 40 GPa whisker 160 GPa
•
The isolation of MF and CNW from wood resources•
Whiskers are the crystalline parts of cellulose
Cellulose Nano-entity Research Value Chain: Economics and Environment
Cellulose Whiskers
Cellulose Nanofibers Isolation Process
Cellulose Nano Whiskers from MCC
Commercial available microcrystalline celluose (MCC)MCC is aggregated cellulose crystallites which needs
to be swelled or isolated before processing to nanocomposites
High mechanical properties, theoretical modulus calculated to ~167GPa (Tashiro.K., Koayashi. M, Polymer (32), 1991)
High Shear Refining of Cellulose (Nano)-fiber Production
Isolation of Cellulose Nano Whiskers
Acid hydrolysis with HCL or H
20 µm 200 nm
MCC 10-15 µm Cellulose Whiskers
Nanofiber Isolation by Heat Treatment
Raw Plant Fiber
Steam explosionBleaching
Acid HydrolysisCrushing
Nanofibrils
Mechanical agitation Acid Treatment
Isolation of Nanocellulose From NF
Pressure Drop
Nanostructure Characterization
Microscopy
Scanning Electron Microscopy(SEM-5 nm, ESEM -1 nm-especially
for biomaterials)
Transmission Electron Microscopy(TEM-0.2 nm)
Atomic Force Microscopy (AFM-1nmx,y , 0.1nmz)
Biobased nanoreinforcements and nanocomposites (≤3nm)
Raw Coir Fiber Steam Exploded Coir Fiber
Bleached Coir Fiber
ESEM Micrograph of Acid Treated Coir Nanofibril Suspension
Transmission Electron Micrographs of Cellulose Nanofibrils of Coir
•Well defined nanofibrils•The diameter of the whiskers are ~ 5nm•Narrow size distribution, reduced agglomerates
Atomic Force Microscograph of Coir Whiskers
Well defined nano whiskersThe diameter of the whiskers are ~ 15nmNarrow size distribution, no big agglomerates
HCL prepared whiskers better thermal stability compared to H2
SO4
K. Oksman, P. Syreand
D. Bondeson, Patent appl. NO20065147 and US 10/560190 D. Bondeson, P. Syre, K. Oksman, Journal of Biomaterials and Bioenergyin
press
Thermal Stability of the Whiskers
IsolationFind suitable chemicals
Freeze dryingRe-aggregates
Re-dispersionDifficult in other than water
Preparation of CNW
Processing of Nanocomposites
Preferred processing medium = water because of high stability of aqueous polysaccharide nanocrystal
dispersions.
Matrix = hydrosoluble polymers
Water evaporation Nanocomposite film
Nanocomposite Process: Solution Casting
Advantages: + low temperature+ only a few grams+ uniform thickness
Drawbacks: -
use of solvent-
lab scale
- time consuming-
difficult if non water soluble polymer are used
Processing of Nanocomposites
Alternative = use of an aqueous dispersed polymer (latex)
Water evaporation (T>Tg) Particle coalescence Nanocomposite film
Alternative = non aqueous systems
Dispersion of polysaccharide nanocrystals in an organic medium
Coating of nanoparticlessurface with a surfactant
Chemical modificationof nanoparticles surface
High specific area : high amount of surfactant
(x4 for tunicin
whiskers)
Involves reactive OH groups from the surface
Processing of Nanocomposites
Processing of Nanocomposites
Alternative = non aqueous systems
Dispersion of polysaccharide nanocrystals in an organic medium
Use of anadequate solvent
Solvent exchange procedure
Dispersion of cellulose whiskers in Dimethylformamide(DMF), dimethyl
sulfoxide(DMSO) or N-methyl surface modification
Water Acetone Toluene
Alternative = dry nanoparticles
Processing of Nanocomposites
Aggregation of polysaccharide nanocrystals
Filtration of the suspension film + immersion in a polymer solution
Melt extrusion
Bio-nanocomposite Solid Phase Processing
Nanocomposite Process: Melt Compounding
Mixing the melt polymer and nano
whiskers in a twin screw
extruderPossible to scale upPossible to compression mold
or injection mold samplesHigh temperature processLarge amount of materials is
needed
Challenges in Melt Compounding
5 µm
100 nm
Feeding of nano whiskers into the extruderLiquid feeding – Suitable feeding liquid – Concetration– Remove the high amount of liquidDry feeding– Avoid re-aggregation druring drying– Low bulk density material– Get uniform dispersion of nano whiskers – Processing parameters; Surface modifications– Compatibilizers; Processing aids
Thermoforming
Injection
Moulding
Electrospinning
Dynamic Mechanical Thermal Properties
The dynamic modulus was improved in elastic and plastic areas and the tan delta peak is moved towards higher temperature, 117°C 148°C better thermal stability
Mechanical Properties
Dramatic improvement of modulus and strengthElongation to break and toughness were decreased
D. Bondeson, P. Syreand
K. Oksman, Journal of Biomaterials and Bioenergy, in press.
Cellulose and Polyurethane Nanocomposite
TEM image of PU/CW XRD patterns of cellulose and PU/C3
Process
Magnetic Field
I. Kvien
and K. Oksman, Orientation of Cellulose Nanowhiskers in Polyvinyl Alcohol (PVA), Applied Physics A, 87, (2007), 641-643.
CNW TEM
PVA PVA-CNW
“The most environmentally friendly thing that you can do for
a car that burns gasoline is to make lighter bodies”
“They (automobiles) will be
lighter and much of them will be
built of plastics developed from
farm products”.Henry Ford, from an article written by James Schweinehart published in The
Detroit News of July, 30rd, 1942.
Automobile Applications
TOYOTA BODY
Composite spare-tyre carrier for Mercedes-Benz A-Class minicar made from banana fibre reinforced composites
Natural Fbres & High Impact?
(Sonntag & Barthel, 2002)
Plant Fibre Utilisation per vehicle (Brazil – 13 kg)
• Front door liners: 1.2-1.8 kg• Rear door liners: 0.8-1.5 kg• Boot liners: 1.5-2.5 kg• Parcel Shelves: <2 kg• Seat Backs: 1.6-2.0 kg• Sunroof Interior Shields:<0.4 kg• Headrests: ~2.5 kg
61
Auto Production by Country
Production (in
Millions) - 2009
Japan 9.62USA 7.22Germany 4.82S. Korea 2.91Brazil 3.10France 2.23
Fox Models: parts made of curauá
FOX Moulded
Headliner
Carrier: 50/50 Curauá
Fiber
+ Polymeric
Resin
FOX Trunk
Lid
FOX Sliding
RoofDeveloped in partnership with UNESP
Artificial Hip Joints
Artificial Ligaments
Biomedical Application
Features of the Nanocellulose PackThree dimensional gauze
With the intensity of a high gel phase, the three dimensional gauze has a close-Knit structure 500 times
that of non-woven fabrics and 10 times its moisture.
Removes dirt through high density structure It is highly absorbent, and with its high density
structure, it effectively stays on and revitalizes the skin, It an also be used for medical purposes.
Deep moisturizing As a deep moisturizing pack, it contains vitamin,
collagen, aloe, chamomile and rosemary, and shows visible results in a short time.
Skin safety It is developed by fermented fruit juice and its safety
has already been verified.
Cosmetic Application (Nanocellulose Pack)
Sanitary Napkin Nanocellulose Coated Sanitary Pad Utilized for the Repeated
Absorption of Menstrual Fluid
Biomedical Application Continued…….
Plate Type Dialyser
Hollow Fibre Dialyser
Surgical Equipments
Disposable Plastic Blood Bag
Biomedical Application Continued…….
Biomedical Application Continued…….
Artificial
Ligaments
Artificial Hip Joints
Biomedical Application Continued…….
Dental Bridges
Biomedical Application Continued…….
Metal-free orthodontic retainers which
strengthens the tooth after Root Canal treatment
Artificial Heart Valve
Biomedical Application Continued…….
Heart Valve Top View
Nanobial Cellulose Membrane
Conformability to the various body contours, maintains a moist environment, and significantly reduces pain
Wound covering for skin problems such as burns and chronic ulcers
Biomedical Application
Packaging: Cellulosic nanofibers perform outstandingly as a oxygen and water barrier in the polymer matrices.Application: food and pharmaceutical packagingRadio Frequency ID Tags: ID tags printed on cellulosic paper possess impressive computer power and RF capability, and are inexpensiveApplication: track commercial products remotely, detect counterfeit drugs and protect product integrity
Biomedical Application
Cellulosic nanofibers have unique mechanical, optical, electrical and chemical properties that can be utilized in a variety of diverse applications.
Successful and positive results have been achieved through the efforts of many dedicative research and studies.
However, the scaling-up and the long-term durability of the nanocomposites remain as a question.
Conclusions
The Future
The future of the materials based on FPC composites depend on many factors, such as:
1. Identification of new products;2. Quality of the products;3. Consumers perception;4. Performance of the products; and5. Identification with innovation
Life is pretty simple:You do some stuff. Most Fails. Some
Works. You do more what works. If it works big, others quickly
copy it.Then you do something else. The trick is the doing
something else
Leonardo da Vinci
75
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ACKNOWLEDGMENTS• CNPq – National Council for Research – Brazil• FAPESP – São Paulo Research Support Agency