ZealaFoam™ A Functional Alternative to Polystyrene Foam
Outline
• Biopolymer Network Ltd
• The ZealaFoam™ process
• Fish box production and testing
• Scale up and current research
Biopolymer Network Limited
Biopolymer Network Limited
• New Zealand research company
• Established 2004
• Research & Technology Focus
– NZ Natural Extracts & their Biopolymer Products
• plastics‐coatings‐cosmetics
• ultrafine starches and functional proteins
• tannin – Non‐wood Natural Fibres & Biocomposites
– Thermoset Biobased Resins
– Biofoam Technologies
The ZealaFoam™ Process
The ZealaFoam™ Process
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Use commercial polylactic acid (PLA) beads
Particle foam approach
Drop‐in technology for polystyrene moulders
CO2 as a "green" blowing agent
Patented US 8283389, also granted NZ, Australia, China and Japan. Pending Canada, Europe.
ZealaFoam™ Process
Impregnated with CO2
Pre‐foamed with heat
Fused with heat
ZealaFoam™ Technology: Impregnation
Commercial PLA beads
• Liquid CO2 as a "green" blowing agent • Low pressures / ambient temperatures
• Short impregnation time ZealaFoam™ Technology: Pre‐foaming
Impregnated PLA beads
• heat (steam, water, air)
• do not instantaneously foam
• short foaming time (size / density / temp dependant)
• do not need a second impregnation after being pre‐foamed
ZealaFoam™ Technology: Moulding
Pre‐foamed PLA beads
• Rapid moulding
• Current density >24 g/L
• No additional chemicals/materials required
Our ZealaFoam™ technology: Final foam
• Fine cell structure
ZealaFoam™ : Molecular weight distribution
• Molecular weight of PLA not compromised during prefoaming or moulding
PLA original
PLA extruded
PLA pre-foamed
PLA moulded
Lab Scale
Impregnated with CO2
Pre‐foamed with heat
Fused with heat
Pilot Plant CO2 Impregnation
Easy to use
1 tonne pallet of beads
Colour for difference
Pilot Plant Impregnation
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Recycling of CO2 critical for cost
Adapted existing equipment to process
Easy installation and operation
Small footprint – actual and environmental
Pilot Plant Pre‐foaming
Density determined by pre‐foaming
Impregnated beads
Pre‐foamer
Pre‐foamed beads
Pilot Plant Moulding
Approx 43 L Fish Box
750 x 330 x 240 mm (L x W x H)
Fish Box Production and Testing Export Simulation Trials
• Use current export packing methods
– Fresh fish packed directly on ice
• Simulate temperature profile (NZ – Singapore 38 hours)
• Record temperatures both inside fish and internal box wall temp
• Compare ZealaFoam™ and EPS performance
Export Simulation Results
Mean Air Temp at Surface of Boxes
Mean EPS Internal Wall Temp
Mean ZealaFoam™
Internal Wall Temp
Export Simulation Results
Mean Air Temp at Surface of Boxes
Mean EPS Fish Temp
Mean ZealaFoam™ Fish Temp
Mechanical Testing Trials
• Industry driven property testing
• Lab testing based on industry standards
• Densities of EPS / ZealaFoam™ boxes differed
ZealaFoam™ Mechanical Properties
EPS
ZealaFoamTM
Shear modulus (MPa)
3.2
3.0
Shear strength (MPa)
0.12
0.11
Shear stress, maximum (MPa)
0.17
0.18
Cross-breaking strength (kPa)
327
418
At 25 g/L
Density
(g/L)
Thermal
conductivity
(W/m.k)
EPS
~30
0.032
ZealaFoamTM
~30
0.032
Stack Test
• 18 kg of PLA inside
• Compression tested at 10 mm/min
• Buckling at maximum load
• Max load at ~12 kN –
GOOD
• AS 2582.3
Drop Test
• 25.3 kg of PLA inside
• Box put in freezer for 24 hours
• Box dropped 3 times from 500 mm (on corner, short edge and long edge)
PASS
• AS 2582.4
Puncture Test
• A 7 kg, 40 mm diameter dart was dropped from 100 mm onto a 150 mm diameter plastic disk
• Repeated on each surface and inspected for indentation
PASS
• IATA Dangerous Goods Regulation 42 ed Paragraph 6.5.2
Scale up and Current Research
Commercial Scale up ‐ Challenges
• Beads may require resizing
• Impregnation required
• Looks like EPS, uses same equipment but  Very different processing windows – impregnation –
pre foam ‐ mould
 Different processing parameters – temp / pressure
 Foam not as heat tolerant
Current Research
Ongoing research program
• Use of additives to alter properties
• Addition of biomass
Use of Additives to Alter Properties
• Foaming increases HDT of PLA • Modifying PLA can increase the HDT of PLA foam
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Extension (mm)
-0.5
PLA (4060D) 1.5mm
PLA + Additive 1
PLA + Additive 2
-1
-1.5
-2
Temperature (C)
Addition of Biomass
• Biomass can be added to PLA prior to impregnation
• Successful pre foam and mould
• Reduce cost and alter properties
• Further work on going
Acknowledgements