Development of Composites Based on Natural Fibers M.T. Ton-That & J. Denault Industrial Materials Institute The Institute of Textile Science Ottawa, ON April 13, 2007
Presentation outline Opportunities with natural fibres Challenges of natural fibre composites Canadian Natural Fibre Initiative on Flax and hemp fibre biocomposites Conclusions
Polymer Composites Polymer Composites = Reinforced Plastics Reinforcing phase ¾ Reinforcement usually has much greater mechanical properties and serves as the principal load-carrying members.
¾ Reinforcing effect determined by interface, aspect ratio, distribution and orientation The matrix ¾ Plays a role of a binder to keep the fibers in a desired location and orientation. ¾ Transfers load to the fiber through the fiber-matrix interface. ¾ Protects fiber from environmental damage.
The fiber-matrix interface plays a decided role on the transformation of load from the matrix to the fiber. Composites are more favourable than plastics
Eco-Composites: Composites of The Future Respond to the needs of materials in the 21st century ¾ ¾ To To cope cope with with limitation limitation of of petroleum petroleum supply supply ¾ ¾ To To cope cope with with environmental environmental pollution pollution concern concern
Economically favourable composites made of ¾ Sustainable ustainable crop-derived crop-derived plastics plastics ¾ ¾ Inexpensive Inexpensive crop-derived crop-derived fibres fibres as as reinforcement reinforcement
Case of success ¾ ¾ Natural Natural fibers: fibers: wood, wood, hemp, hemp, flax, flax, kenaf kenaf ¾ ¾ Bio-based Bio-based polymer: polymer: PLA PLA from from corn corn and and sweet sweet potato potato
Attention: bio-based products are not always sustainable
Natural Fibres vs Synthetic Fibres Bast Fibres: Flax, Hemp, Kenaf, Abaca, Banana, Bamboo, Jute, Totora Leaf Fibres: Sisal, Curaua, Fique, Phormium, Palm trees, Caroa, Kurowa, Pineapple Seed Fibres: Cotton, Capok Fruit Fibres: Coir, African palm Wood Fibres: soft & hard wood
Natural fibres
100 80 Price (cent/lb) 60 40
Wood fiber
CaCO3
Natural fibers
0
Fiber glass
20
NF Composites in North American
NF composites market
Driving force: purely economic Million lb
The market for NF composites in North America: mainly for construction ¾ 2000 = 200,000 tonnes ¾ 2005 = 3X
400 350 300 250 200 150 100 50 0
Other natural fibers Wood fiber
1980
1990
2000
Construction applications Toronto Broad walk
Deck
Mighty Mount Rusmore
Play ground
Construction applications Siding and soffit products
Pool
Marina
NF composites in Europe Consummation in tone of natural fibres in automotive industry in Europe
Driving force: Government Legislation Recycling concerns being driven by EU regulations end of life vehicle disposal: Jan 1st, 2005: 80 wt%; Jan 1st, 2015: 85 wt% GHG emission limit and tax incentive
Automotive Parts Made of NF Composites Volkswagen: back of seats,door panels, trunk panels (Golf, Passat, Variant, Bora, Fox, Polo) Audi: back of seats, side panels, trunk covering, speakers holders (A2, A4, Avant, A6, A6 Avant, A8) BMW: door panels, headliners, trunk floor panel (Serie 3, 5 and 7) Daimler Chrysler: door panels, business tables, padding-pillars reinforcing, dashboard parts (Class A, C, E and S) Opel: headliners, door panels, dashboard parts (Astra, Vectra, Zafira) Peugeot: back of seats, trunk coverings (406-607) Renault: rear shelf (Clio, Twingo) Mercedes Benz trucks: front sections for the trucks. ¾ HSK LS 1938, internal engine cover, insulation for the engine, sun-blades, interior insulation and bumper. ¾ HPN L 1622 -internal insulation; wheel box; roof; and back cover.
Automotive Parts Made of NF Composites
Advantages of Natural Fibre Reinforcement Renewable source of raw material Biodegradable Sustainable? Excellent specific strength and high modulus ¾ High flexural and tensile modulus -up to 5×base resin, high notched impact strength -up to 2×base resin
Reduced density of products Lower cost Reduced tool wear Safe manufacturing processes ¾ No airborne glass particles, relief from occupational hazards. ¾ Reduced dermal and respiratory irritation and no emission of toxic fumes when subjected to heat and incineration
Challenges of Natural Fibre Reinforcement Challenges ¾ Concerns over fibre consistency/quality ¾ Low impact strength (high concentration of fibre defects) ¾ Problem of stocking raw material for extended time Possibility of degradation, biological attack of fungi and mildew Foul odor development
¾ Fibres are hydrophilic Issues of compatibility with polymers: fibre-matrix interface and fibre dispersion challenges Sensitive to humidity
¾ UV resistance – not better than plastics ¾ Fibre degradation during processing ¾ Fibre orientation and distribution
Solutions ¾ Fibre treatments ¾ Compatibilization ¾ Textile technologies: mat and fabric structures
Composite Evolution Structural Composites
Platform 1950 Technologies
Structural composites Thermosets
and materials
1980-2000 Thermoplastics Nanocomposites
2005 Biocomposites Nanocomposites Biobased polymers
Industrial Sectors
Microelectronics Ground transportation Aerospace
•Biomedical •Transportation •Construction •Energy •Sport •Environment •Aerospace •Packaging…
Natural Fibres in Canada National level: federal government: sustainable economy ¾ Bio-fibres to produce value-added products: chemicals, textile, composites, etc ¾ Agriculture and Agri-food Canada: 145 M$ funding for this year alone: multidisciplinary research (soil, genetic modification, refinery, extraction, processing) Canadian biomass innovative network (CBIN) Carbonhydrate: starch (wheet, corn, etc) Oil: canola Cellulose: flaxseed fibres and hemp Present acttraction: triticale corp in Western Canada (carbonhydrate and cellulose)
Local level: ¾ ¾ ¾ ¾ ¾ ¾ ¾
AB: BioAlberta, AVAC NB: BioAtlantech SK: Flax Canada 2015 ON: Bioproducts Business Network, AUTO 21, Ontario Agri-Food Technologies (OAFT), QC: Centre québécoise de valorisation des biotechnologies BC: BioProducts BC BIOCAP
Natural Fibres Initiative for Biochemicals and Biomaterials
AAFC
Kemestrie
Saskflax NRC-PBI
Biolin
Feedstock Producer John Baker (Stone Hedge Hemp)
BioEnergy/ BioFuel
NRC-BRI
Harvest + PostHarvest
Preparation of Feedstock
Seed Oils Process Heat
BioMaterials
Biolin Saskflax
Black boxes – Industry Research Contributions Red boxes – Project Modules
Module 1
Processing of Fibers •Two methods: 1 – Enzymatic 2 – ‘Green’ Mechanical/Chemical •Two Primary Tracks 1 - For Fibre 2 - For Biochemicals
NRC-IBS
TRACK 1 Biocomposites
NRC-BRI
End Users (Private Sector)
NRC-ICPET
TRACK 2 BioChemicals • such as ferulic acid
NRC-ICPET
Module 2 AAFC
Biopolymers
NRC-IBS
Ferulic Acid Platform
Module 3
Module 5 NRC-IMI
NRC-BRI NRC-IMI
Module 4
• Composite Innovation Centre (Links to Boeing, Dow BioProducts and others), Biolin, Hemptown
Related CBIN Threads
GHG Reduction
NRC-IMI NRC-BRI NRC-ICPET
Biocomposites Objectives Development flax (hemp) fiber composites and applications based on synthetic (PP) and biobased (PLA) polymers Improvement of processability Improvement in mechanical properties, humidity resistance and flammability resistance
Evaluation of the performance of value-added products coming from recycling sources Use of recycled plastics
Processing Extrusion: short fibre Injection moulding: short fibre Compression moulding: short, long, continuous, matt, fabric Flax composite compound
Mat or fabric construction ¾ Compression moulding ¾ Thermo-forming
Dried blend of flax, polymer and additives
NF Composites
IMI Patented technology licensed to Formulation based CaO additive
5000
75 Modulus
65 3000 55 2000 45 1000
0
35 Recycled PP
Licensed technology applied to transportation and construction sectors
Wood com posite
IMI 's com posite
Increase of material cost (%)
Improvement in flexural performance (%)
3.6
28
* Compared with commercial system
Flexural stress (MPa)
Flexural modulus (MPa)
Stress
4000
Roles of CaO CaO Absorbs humidity in wood Neutralizes acidity in wood Æ minimize degradation during processing Reacts with maleic anhydride group of coupling agent ÆImprove interface between wood and PP matrix ÆIncrease molecular weight of coupling agent ÆLimit a loss in toughness and impact
Thermal and flammability resistance Improvement of the thermal resistance Slow down the burning process of the composites since the burning rate of the sample with CaO at 1 min (L1) and 5min (L5) is smaller than that of the REF. No
T10%
T20%
(oC)
(oC)
Weight loss at 500oC
No
L1
L5
(mm)
(mm)
No CaO
12
65
10% CaO
7
36
(wt%) No CaO
334
364
91
10% CaO
346
398
73
Recycling Wood-PP composites (with maleic anhydride coupling agent and CaO) can be reground, extruded and injection moulded 3 times without important loss of performance 6500
30
6000
28
5500
26
5000
24
4500 1st process 2nd process 3rd process
Unotched Izod impact strength 2 (kJ/m )
Tensile strength (MPa)
Strength Modulus
110
Tensile modulus (MPa)
32
100
90
80
70 1st process
2nd process
3rd process
Flax Fiber Composites Compression moulding
40
7000 5500
35 4000 2500
25
1000
30 %
30 %
FL AX
FL A X+ PB 30 31 % 50 FL A X+ EP 30 30 15 % FL 30 AX % +E FL 43 AX +E 43 +C aO
30
Modulus and strength of the composites improve significantly with the presence of coupling agent Type of coupling agent also plays an important role The presence of CaO provide a great increase in modulus
Tensile modulus (MPa)
Strength Modulus
PP
Tensile strength (MPa)
45
Interface No coupling agent Very poor interaction between the fiber and the matrix
Interface With coupling agent and CaO Good interface
Mechanical properties –
Strength
35.00
Modulus
4000
30.00
3000
25.00
2000
20.00
1000 PP
30% FLAX +E43 +CaO
2
5000
Tensile modulus (MPa)
Tensile strength (MPa)
40.00
Izod impact strength (kJ/m )
Injection moulding 18.00
15.00
12.00
9.00
6.00 PP
30% FLAX +E43 +CaO
Flax fibres improved significantly the performance of PP, but the properties can be further improved ¾ Fibre retting and the fibre isolation process is not optimized ¾ Flax composite processes are not optimized
It should be interesting to work with flax fabric as reinforcement
Conclusions Natural fibres like wood, ricehusk and flax can improve significantly the polymer performance The composite properties are determined by many different factor: fibre source, formulation, processing equipment and processing parameters The incorporation of some selective mineral fillers can greatly improves the thermal and the flammability resistance, the stiffness and the impact properties without sacrifying the strength. Forms as continuous fibres and fabric should be of great interest for producing high performance composites!
Opportunity of textile industry in composites Mass productions ¾ Transformation of NFs into different forms of reinforcement for composites, such as unidirectional NFs, NF fabrics, NF matt, comingle of NFs and synthetic polymer fibres, at low cost and low energy consumption ¾ Hybrid of NFs or NF and synthetic fibres ¾ Fibre treatment to improve performance and overcome limitation
Special applications ¾ Functionality: surface coating (thermally and electrically conductive)
Recycling of fibres???
