Typical PSA dispersion can be much improved in adhesive performance by adding tackifier dispersions. Especially the tack and peel on low surface energy sustrates like untreated PE and PP is affected positively, while cohesion is still sufficient for the application. When developing tackifier dispersions we need to walk a fine line between creating a stable final adhesive dispersion and not affecting the tackifier action negatively. In the current presentation we will show the nature and the action of the tackifier, the surfactant, and the influence of surfactant packages to come to a stable, fast running PSA dispersion which has excellent adhesive performance.
2. Content
• Introduction Arizona Chemical
– Sustainable, Green and low Carbon Footprint
• Rosin Ester Tackifiers
– Their action – looking at molecular scale
– Chemistries
• Rosin Ester Dispersions
– How are they made?
• Stable adhesive dispersions with tackifiers
– Testing at high shear
• Performance
• Conclusions
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3. At Arizona Chemical we believe the key to
success is through understanding our
customers’ businesses, working in close
partnerships for mutual benefit.
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4. Our company
• 10 Manufacturing facilities
• Broad-based research and development
• Regional headquarters in Jacksonville, Florida and Almere, Netherlands
• 2 Research, Development
& Technical Service labs
– Almere, The Netherlands
– Savannah, Georgia US
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5. Our locations
Oulu
Sandarne
St. Petersburg
Chester le Street Almere
Dover
Gersthofen
Pensacola Savannah Niort
Valdosta
Panama City
Jacksonville
Miami
Singapore
10 production sites, 5 sales offices
US Headquarters in Jacksonville, Florida
European headquarters in Almere, The Netherlands
Sales offices
Production sites
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7. Sustainability
Biorefining- A New Word for our Decades of Experience!
Biorefinery:
“A facility that integrates biomass conversion processes and equipment to
produce fuels, power and added-value chemicals from biomass”
Source: Wikipedia
Renewable raw Co-product of pulp Refining and Providing sophisticated products
material production producing chemicals for the global chemical industry
Arizona
PULP MILL
Chemical
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8. Arizona Chemical creates value
from the tree
TOFA
CTO
Pulp
DTO
Rosin
Pitch
CTO
Kraft
Process
CST
α-Pinene
β-Pinene
CST
δ-3-Carene
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9. Arizona Chemical- Biorefining in its
Truest Sense
“By producing multiple products, a biorefinery takes advantage of the various
components in biomass and their intermediates therefore maximising the value
derived from the biomass feedstock.”
Source: Wikipedia
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10. The CTO and CST derivatives produced by Arizona
Chemical in Oulu and Sandarne have a lower carbon
footprint compared to substitutes
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13. Green in Three Ways
TRUE BIOREFINERIES
TRUE BIOREFINERIES
Extracting the most value from
Extracting the most value from
the biomass
the biomass
LOW CARBON FOOTPRINT
LOW CARBON FOOTPRINT CUSTOMERS’ GREEN ADVANTAGE
CUSTOMERS’ GREEN ADVANTAGE
Nordic refineries with
Nordic refineries with Additional environmental benefits as
Additional environmental benefits as
demonstrated low footprint
demonstrated low footprint an enhancement to the biorenewable
an enhancement to the biorenewable
compared with similar operations
compared with similar operations content
content
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16. Rosin Ester Dispersions
• Upgrade adhesive performance for
dispersions
• Need for high solids content
• Easy in use
• Ever faster running coaters
• “Green” – APEO free and renewable resource
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17. Why would an adhesive stick?
• What is the gain for the molecules?
– Basic thermodynamics: Free Energy
∆ G = ∆ H - T∆ S
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18. Basic thermodynamics
∆ G = ∆ H - T∆ S
Free energy:
gain if negative Entropy:
value order = loss
(negative),
Enthalpy:
thus bad
interaction = gain
with polymer
(negative value)
chains
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19. Adhering to low surface energy substrates
• No possibilities for specific interactions
– only Van der Waals
• The surface of PE is “liquid-like”
– …and bonding to a liquid surface …
Very little inter-chain interaction
(just Van der Waals)
Top
Small difference in free energy
bulk and top-layer Bulk
Very mobile chains (Tg: -90 C!)
Resulting in “liquid floating top”
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20. Tackifiers work by bridging the top…
Work almost like a surfactant
Bonding two phases…
Adhesive polymer
Tackifier
molecules
Small
Molecules have
little issue with Top
entropy! Bulk
∆ G = ∆ H - T∆ S
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21. Tackifying resins based on rosin
• Bonding
– The molecule has 2 distinct areas
CH3
• Lipophilic
enabling embedding in apolar areas
CH3
CH3
• Polar
for interaction with the
adhesive polymer
HO2 C
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22. Tackifying resins: Rosin derivatives
• Chemistry
– The 2 functional groups also allow versatile modifications
CH3
• Esterification
• Disproportionation CH3
CH3
• Hydrogenation
• Polymerisation
or dimerisation
• “Fortification”
HO2 C
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23. Esterification – Rosin esters
Number of rosin molecules
2 3 4
CH3
H3C
CH3
CO O
C H2
COO H2C CH2 OOC
O COO CH C
COO H2C CH2 OOC
H3C H2 H2 CH2
C O C CH3
C
C C O
O H2 H2 OOC
O
H3C
CH3
Diethylene Glycol Ester H3C
Di-ester Glycerol Ester
Tri-ester Tetra-ester
Rosin Pentaerythritol Ester
liquid 85ºC 100ºC
Softening point,ºC
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24. Rosin ester dispersions
Dispersion of a rosin ester in water
with surfactant(s) and possibly other additives.
CO O
C H2
CO O C H
C H2
O O C
G lycerol Ester
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25. Dispersing rosin esters
• In a dispersion the rosin ester is considered to be
the oil phase
How does a rosin
ester disperse in water?
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28. Adhesive dispersion
• Typically acrylate polymer dispersion
– Optimised for fast trouble free running
• Add 20 – 40 % rosin ester dispersion
– To improve tack and peel
• BUT: Polymer – resin mixture can become
sub-optimal for high speed running
– … if not carefully designed re surfactant package
– Final dispersion mixture needs to be stable
at high shear stresses
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29. Shear stability in high speed coating
Suspect Adhesive
Good Adhesive
25,000 sec-1 with a 20 micron gap
- Suspect would run OK on Gravure or Curtain, but not on Slot-Die
- Good adhesive runs well on all three
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30. Optimised surfactant packages
• Make the total adhesive – tackifier dispersion
mixture stable
– even at high loading, at the high shear stresses
seen at high coating speeds
• Prevent sedimentation
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31. Effect of surfactant package
Old formulation
New formulation
low visc
New formulation
high visc
Market sample
Shear Rate = 25,000 s-1, Gap = 10 microns
running
time
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32. Adhesive performance
• Surfactant undoubtedly has impact on
adhesive performance
– It counteracts the “surfactant action” of the resin
– Hence negative for both peel and shear
– Lower surfactant level should be better
– …need careful balance for optimal stability
but this can be done!
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33. Comparison performance
14
Optimised
12 surfactant
package
10 system
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6
4
2
0 Tackified system
Tack PE Neat system
Tack Steel
Peel PE
Peel Steel
Shear
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34. Examples commercial grades
• Aquatac® XR4316 • Aquatac® XR4324
– General purpose high solids – Coater-ready when added
product to adhesive polymer
– Designed for use on curtain – Designed for use on curtain /
coaters gravure / slot die coaters
• High mechanical stability
• Unique wetting package
• Low viscosity included
• High mechanical stability
• low viscosity
– Good adhesion / cohesion
– Good adhesion / cohesion
properties with several
polymers properties with several
polymers
– APEO free – APEO free
Copyright Arizona Chemical
Confidential 34
35. Rosin Ester Dispersions
Upgrade adhesive performance for
dispersions
Need for high solids content
Easy in use
Ever faster running coaters
“Green” – APEO free and renewable resource
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36. Conclusions
• It is possible to design optimal surfactant
packages
– Combining excellent high shear stability
– …Without impeding adhesive performance
• Rosin ester dispersion upgrade adhesive
performance drastically
• Ideally, each polymer – resin combination
needs to be studied individually:
Let’s work together
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37. Contact Details
Dr Evert Smit
Technical Leader Resins
Arizona Chemical
Transistorstraat 16
1322 CE Almere
The Netherlands
Mobile: +31 653 29 50 32
Office: +31 36 54 62 924
evert.smit@azchem.com
http://www.arizonachemical.com
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