1. How to tailor your material for
customer needs –
PLA coffee cup case study
Derek Atkinson - Purac
François de Bie – Purac
Sicco de Vos - Purac
Karin Molenveld – WUR
Gerald Schennink - WUR
Presenting to:

2. Outline
 Origin of the project
 Project partners
 Material development
 Results from composting study
 Next steps & Summary
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3. Market pull - Origin of the project
 In 2009 Wageningen University defines a
“ Sustainable business policy”
 Objective is to reduce the ecological footprint of the university
and encourage sustainable business practises
 Formation of working group: “Bioplastics in catering”
 Wageningen UR
 Facility service & Food and Biobased Research (FBR)
 Province of Gelderland
 Douwe Egberts
 Albron (catering)
 Other stakeholders
 The working group evaluates the possibilities & benefits
of introducing biobased materials in catering
applications – focus on coffee cups
Wageningen university uses 2.5Million PS cups/year
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4. What is the most environmentally
friendly coffee cup ?
PS PLA Paper/PLA Porcelain
 Carbon footprint: cradle to gate vs cradle to grave
-> Impact of end of life options ?
 Technical requirements
 Consumer experience
-> Multiuse vs single use ?
-> Separate collection system ?
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5. Technology push - Origin of the project
 In 2008 Purac and
Wageningen UR*
start a project.
 PLLA/PDLA
homopolymers
 Objectives:
Develop high heat
injection moulding
compounds in PLA
*) Wageningen University & Research centre,
Food & Biobased Research
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6. PLA coffee cup project kickoff
Technology push Market pull
Industrial
Partner
Develop a PLA coffee cup that:
- Can withstand hot coffee / 93oC
- Can be produced on existing PS
coffee cup production lines
- Can reach the same thermoforming
speed as PS today
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7. Feasibility study
 Several material formulations created
 High heat PLA concept of Purac based on PLLA/PDLA
 Compounding and sheet extrusion at Wageningen UR
 Thermoforming using industrial equipment and moulds
 Conclusions
 Processing conditions are of major importance (hot mould)
 Crystallisation speed of PLA homopolymers is sufficient
 Short cycle times (1-2 seconds) are possible
 See Table on next slide
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8. Results feasibility study on
thermoformed prototype cups
Conclusion:
Even at short cooling rates, PLA homopolymers
can reach a high level of crystallinity
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9. Results feasibility study
 Processing speed is OK .. BUT .. cup stiffness,
when filled with hot coffee (93°C), is NOT sufficient.
Amorphous PLA
Semi-crystalline PLA
E- modulus MPa
Target stiffness
50 93 100 150
Temperature oC
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10. How to increase stiffness at 93°C ?
Combine PLA homopolymers with fillers:
 Fillers increase the stiffness
 Fillers can introduce brittleness
 Fillers can impact crystallization behaviour
Calcium Carbonate (chalk) Talc
 Cheap  More expensive
 Limited effect on stiffness  High effect on stiffness
 No influence on crystallisation  Strong influence on crystallization
speed speed
Conclusion:
PLA homopolymers, in combination with a filler,
have an acceptable stiffness over the required
temperature range. ( see chart on next page )

11. DMTA - effect of fillers & crystallinity PLA 6400
1,E+10
1,E+09
1,E+08
E’ (───)
[Pa]
1,E+07
1,E+06
0x Unfilled PLA - amporhous
Filled PLLA homopolymers
7x at 115C
1,E+05
– high crystallinity
1,E+04
0 50 100 150 200
Temperature [°C]
Conclusion:
PLA homopolymers, in combination with a filler,
have an acceptable stiffness over the required
temperature range.
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12. Results reformulations with fillers
Promising formulations tested at pilot scale
 PLLA and PDLA homopolymers from Synbra/Purac
 Compounding done by Wageningen FBR
 Sheet production and thermoforming at industrial partner
Various formulations with following ingredients:
1) PLLA Homopolymer
2) PDLA Homopolymer
3) PLA
4) Filler
5) Nucleating agent
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13. Results semi-industrial trials
PLLA homo
polymers
polymers
PLA co
Conclusion:
The best results could be obtained with
combination of PLLA and PDLA homopolymers
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14. Main conclusions on thermoformed
PLA hot drink cup
 Thermoforming of high heat PLA is finding a balance
between formability and crystallization speed
 The best results could be obtained with combination of
PLLA and PDLA
 Fillers are necessary to provide sufficient stiffness above
the Tg of PLA
 Replacement of amorphous PS cups is possible
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15. Biodegradation of the PLA cup
 Cups were submitted to Organic Waste Systems (OWS)
to evaluate the compostability.
 Qualitative disintegration is part of EN13432 and is
considered to be the most significant hurdle for
obtaining the compostability according EN13432.
 Only the qualitative disintegration test was performed.
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16. Results from composting tests
Start 1 week 3 weeks 12 weeks
Test conditions:
The samples were added to a bin with compostable
waste @ OWS.
Conclusion:
Does not meet EN13432 standard.
Significant degradation, fungal growth,
size of left over’s 1 x 3 cm.
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17. Next steps and actions
 Finalize large scale industrial production run
 Commercial roll out of PLA cups
 Complete bio-based certification
 Evaluate options for end of life recycling
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18. Summary – key learnings
 Replacing traditional plastics in “high volume”
applications takes time & effort.
 Working closely with expert partners that have
knowhow in different areas of the process increases
the rate of success.
 PLA homopolymers can replace PS in hot coffee cups.
Many thanks to all partners that contributed to this
project:
Industrial
Partner
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19. Questions ? For info please contact d.atkinson@purac.com 19

20. For more information, contact:
Derek Atkinson
Business Development Director
PLA Asia
M +65 9093 9896
d.atkinson@purac.com
No representation or warranty is made as to the truth or accuracy of any data, information or opinions contained herein or as to their suitability for any
purpose, condition or application. None of the data, information or opinions herein may be relied upon for any purpose or reason. Purac disclaims any liability,
damages, losses or other consequences suffered or incurred in connection with the use of the data, information or opinions contained herein. In addition,
nothing contained herein shall be taken as an inducement or recommendation to manufacture or use any of the described materials or processes in violation
of existing or future patent of Purac or any party.
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