26 Feb Applications of FiberLean microfibrillated cellulose in and out of the paper industry
Biopolymerkolloquium, Potsdam, 24th January 2019
Jonathan Phipps
FiberLean microfibrillated cellulose – what is it?
- Simple wet media grinding process reduces cellulose paper pulp fibres to microfibrils
- Product has fibrils and fibre fragments over a wide range of length scales
- Fibres are mixed with micron-sized mineral particles to aid separation of fibrils
FiberLean microfibrillated cellulose – microstructure and properties
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FiberLean production for paper applications
- Satellite plant located at paper mill (3 operational)
- Pulp received, processed and delivered at low solids (<4% cellulose in water)
- Product fed direct to papermaking process (no dewatering or drying required)
Rheological properties of FiberLean Microfibrillated Cellulose
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FiberLean in Papermaking
Papermachine Schematic
Paper structure, fillers and microfibrillated cellulose
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Optimisation of filler content
Property Changes with microfibrillated cellulose and filler increase
Paperboard grades
![]() Corrugated board |
![]() “White top” |
![]() Folding boxboard |
- Packaging grades are multilayer structures because they need to be resistant to bending
- Filler is used only in the surface layers for optical and printing properties
- Layers are formed individually and pressed together when wet – web is only placed in tension afterwards
Paperboard stiffness
- Bending a sheet of material causes stretching of the outer surface and compression of the inner surface
- At small deformations, resistance to stretching and compression must be equal
- Resistance to bending – bending stiffness – is therefore directly related to the elastic modulus of the material
- Modulus (E) = Force / (x-section area x strain)
- For paper, x-section area depends on pressing and calendering, so instead we define tensile stiffness index (TSI): –
TSI = Force/ (width x gsm x strain) - TSI is not very sensitive to pressing or calendering
For a single layer, Bending stiffness = (E x thickness3 ) /12
= (TSI x gsm x thickness2) /12
Stiffness is very sensitive to thickness
FiberLean mfc in paperboard outer layer
- Addition of mfc allows filler increase and weight reduction without loss of tensile stiffness
FiberLean microfibrillated cellulose in boxboard – full scale example
Improved brightness, constant stiffness, lower cost
Coating FiberLean Microfibrillated Cellulose at the ‘wet end’
Alternative method for making white top paperboard
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Coating FiberLean Microfibrillated Cellulose at the ‘wet end’
![]() Coating onto wet, rough base at 500 m/min |
![]() High quality print on low speed coated base |
![]() Coating from 500 m/min trial |
Using FiberLean Microfibrillated Cellulose as a precoat for barrier coatings
- Food packaging needs water and/or oxygen vapour barrier
- Aim to replace laminated polyethylene layers with water-based latex barrier coatings
- Recyclable, repulpable, reduction in plastic content
- Current paperboard products are too rough to allow defect-free coatings
- Microfibrillated cellulose applied by wet end technique provides enhanced smooth surface
Porosity and Barrier properties
Sample Details | Base Paper | Base Paper + MFC Layer |
Base Paper + barrier coating |
Base Paper + MFC + barrier coating |
Plastic Coated Freezer Paper |
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Base Layer | g/m2 | 32 | 32 | 32 | 32 | Unknown |
MFC Layer | g/m2 | 0 | 9 | 0 | 9 | |
Coating Layer | g/m2 | 0 | 0 | 14 | 12 | |
COBB (Water penetration) | g/m2 | 50 | 58 | 46 | 1 | 0.8 |
Solvent resistance (1=lowest, 16=highest) | g/m2 | <1 | 16 | 3 | 16 | 16 |
Water Vapour Transmission (38C, 95% RH) | g/m2 day -1 |
1031 | 992 | 351 | 23 | 45.4 |
Using Microfibrillated Cellulose as a thickener in decorative paint
Component | Function | Weight% in dry film |
TiO2 | White pigment | 19% |
Kaolin/talc | Mineral extender | 30% |
CaCO3 | Mineral extender | 35% |
PVA latex | Binder | 14% |
HEC/MFC | Thickener | 0.75% |
Others | Additives | 1.25% |
Formulation |
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Pigment Volume Fraction | 66% | |
Wt% solids | 52% |
![]() HEC (hydroxyethyl cellulose) |
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![]() FiberLean MFC |
Dry film properties with Microfibrillated Cellulose – illustrative example
Spinning fibres from suspensions of FiberLean Microfibrillated Cellulose
- Fibre Spinning by hand from syringe with hypodermic needle
- Narrow needles and low solids make stronger fibres – fibril alignment