The document discusses advances in bio-based polyurethane technology for leather processing and coatings. It introduces probiotic technologies that use natural ingredients to soak, degrease and process hides more sustainably with reduced chemicals, waste and emissions. It also describes how polyurethane dispersions are traditionally used in leather finishing but can now incorporate renewable bio-polyols derived from plant oils to create bio-based polyurethanes with lower VOC and improved performance. The technology is advancing rapidly to develop polyurethanes with even higher bio-content and sustainability benefits.

1. Advances in Bio-based
Polyurethane Technology
Sustainability in the Leather Supply Chain Conference
M. Costello, March 31st 2016, Hong Kong

2. ▪ Introduction
▪ Technology for Leather Processing (Probiotics for Leather)
▪ Polyurethane Dispersions
▪ Renewables & Bio-Polyurethanes
▪ Processing & Performance
▪ Future
Advances in bio-based
Polyurethanes

3. ! Leading chemical supplier for leather processing
▪ Key player in the specialty coatings market
▪ 1800 employees
▪ 9 R&D Centres
▪ 38 applications labs/centres of excellence
▪ €600+ Million sales
▪ 6 Business units (4 in leather, 2 for coatings)
Introduction
Stahl

4. Technology
for Leather
Processing

5. Raw Material to Wet Hide Dyeing & Finishing
Probiotic Technology
Soaking & Degreasing
Biodegradable
Reduced COD
Reduced Weight
Reduced VOC
Reduced COD
Retanning4 5 Finishing1 Raw Hides 2 Beamhouse 3 Tanning
Less Salt
Less Water
Higher Yield
Renewable
Polymers
Sustainability-inspired technology
for Leather processing

6. Raw Material to Wet Hide Dyeing & Finishing
Probiotic Technology
Soaking & Degreasing
Biodegradable
Reduced COD
Reduced Weight
Reduced VOC
Reduced COD
Retanning4 5 Finishing1 Raw Hides 2 Beamhouse 3 Tanning
Less Salt
Less Water
Higher Yield
Renewable
Sustainability-inspired technology
for Leather processing

7. Key advantages
! Reduced chemical consumption
! Improved water waste
! Biodegradable
! Non-hazardous, non-toxic
! Reduced odour levels
Natural & Biodegradable
The Proviera® leather bio-chemicals are produced by a fermentation process
using probiotics cultures and natural raw materials.
Proviera®-Probiotics for Leather™
ProSpread and/or
ProSoak (0.1%-0.5%)
ProSpread and/or
ProSoak (0.2%-0.5%)
Replace surfactants, soaking,
agents and enzymes etc.
ProSpread (0.2%)
Rawhide > Prewash > Soaking > Liming + Unhairing >
ProDegreaze
(0.1%-0.4%)
Replace traditional
degreasing chemicals
Deliming >
ProDegreaze
0.1%-0.2% along
with bating enzyme
Bating >
ProSpread
0.2% to 1%
in tanning
Tanning >Pickle > Wet-Blue

8. Raw Material to Wet Hide Dyeing & Finishing
Probiotic Technology
Soaking & Degreasing
Biodegradable
Reduced COD
Reduced Weight
Reduced VOC
Reduced COD
Retanning4 5 Finishing1 Raw Hides 2 Beamhouse 3 Tanning
Less Salt
Less Water
Higher Yield
Renewable
Polymers
Sustainability-inspired technology
for Leather processing

9. Polyurethane
Dispersions

10. ▪ Polyurethanes (water- and solvent-based)
▪ Nitrocellulose (topcoats, non automotive)
▪ Acrylic emulsions
▪ Butadiene (basecoats)
▪ Casein
Polyurethanes are typically used in high performance Leather Finishes:
▪ Durability
▪ Cold crack
▪ Weather resistance
Polymers for Leather
Finish formulating

11. Polyurethane Dispersions

12. Polyurethane Dispersions

13. HO-R-OH + OCN-R’-NCO HO-R [-O-C-N]-R’-NCO
OH
Polyol PolyurethaneDiisocyanate
■ Prepolymer phase:
- Polyol + DMPA + Diisocyanate
- Build polymeric structure
■ Dispersion phase:
- Neutralization
- Water dispersion
- Diamine extension (build molecular weight)
Manufacturing
Process
Polyurethane Dispersions

14. Typical Building BlocksTypical Formula
HO
O
O
O OH
O
O
O
HO
O
O
O
O
OH
O
O
O
O
HO
O
O
O
O
OH
n
n
n
HO
O
O
O OH
O
O
O
HO
O
O
O
O
OH
O
O
O
O
HO
O
O
O
O
OH
n
n
n
HO
O
O
O OH
O
O
O
O
O
O
HO
O
O
O
OH
n
Polyester
Polyether
Polycarbonate
Isocyanate N=C=O
Polyurethane Dispersions
Ingredients %
Polyol 60 -80 (on solids)
Isocyanate 10 -15 (on solids)
Solvent 5 – 10
Water 60 – 70
Additives 0 – 5 (on solids)

15. Renewables &
Bio-Polyurethanes

16. Polyols like polyethers and polyesters can be derived from both petroleum
based resources or renewable plant oils & bio-mass.
Polyurethane dispersions with 40% bio-content have already been achieved
with polyols derived from natural oils.
Cutting millions of years off lead times …

17. nOH
O
nOH
O
OH
O
n
Cat
nnOH
O
OH
O
OH OH
+
m
- H2O
nnO
O
O
O
OH
OH m m
The unsaturated fatty acid from the (eg: rapeseed) oil is dimerized:
Then polymerized with a diol, yielding a polyester with renewable content:
Renewable Resources

18. Building BlocksTypical Formula
Bio-based Polyester:
Isocyanate N=C=O
Bio-based Polyurethane Dispersions:
Building Blocks
nnO
O
O
O
OH
OH m m
Ingredients %
Polyol 60 -80 (on solids)
Isocyanate 10 -15 (on solids)
Solvent 5 – 10
Water 60 – 70
Additives 0 – 5 (on solids)

19. Sourcing:
▪ Canada
▪ China
▪ India
▪ Europe
▪ Australia
Current Usage:
▪ Animal feed
▪ Vegetable oils
▪ Biodiesel fuel
Canola oil
Rapeseed example

20. Processing &
Performance

21. HO-R-OH + OCN-R’-NCO HO-R [-O-C-N]-R’-NCO
OH
Polyol Polyurethane
(with Co-solvent)
Diisocyanate
■ Prepolymer phase:
- Polyol + DMPA + Diisocyanate
- Build polymeric structure
Pre-polymer viscosity is critical in determining the co-solvent
Amount in the final product.
Volatile Organic
Content
Polyurethane Dispersions
Co-solvent

22. Bio-based polyols contribute to a lower pre-polymer viscosity.
Volatile Organic
Content
Polyurethane Dispersions
Low Viscosity Pre-polymer Reduced co-solvent need.
Reduced V.O.C

23. ■ With the latest advances in biotechnology, improved properties have
been achieved for bio-based Polyurethane Dispersions
■ Touch, feel, appearance
■ Film durability performance after hydrolysis
Higher Performance
Bio-Polyurethanes:

24. Bio-Polyurethanes:
Film Performance after Hydrolysis

25. Future

26. Bright Future
Bio-based Polyurethanes
■ Even higher performance
■ Higher % bio-content
How?
■ New bio-polyols (soy, linseed, palm…)
■ Isocyanates (from biomass)
■ Co-solvents (plant-based becoming available)

27. Land use for bioplastics 2014 and 2019

28. Conclusions
Bio-based Polyurethanes
■ Performance is driving the introduction of bio-polymer technology
■ Bio-based polyurethane technology is advancing rapidly
■ Oil price fluctuations can temporarily cloud the long term reality

29. Raw Material to Wet Hide Dyeing & Finishing
Soaking Degreasing
Biodegradable
Reduced COD
Reduced Weight
Reduced VOC
Reduced COD
Retanning4 5 Finishing1 Raw Hides 2 Beamhouse 3 Tanning
Less Salt
Less Water
Higher Yield
High Performance
Polyurethanes based
on Renewables
Sustainable Leather Processing:
Step by Step

30. If it can be imagined,
it can be created
Thank you