Topchim produces organic nanoparticles from poly(styrene-maleic anhydride) (SMA) using various techniques, including imidization of SMA in the presence of oils or waxes to create core-shell nanoparticles, and applies these nanoparticles in coatings for applications like paper, packaging, textiles, and inks to provide properties such as hydrophobicity, barrier properties, and encapsulation of active ingredients. The nanoparticles can be tuned based on the raw materials and processing used to suit different market needs.
1. Surface modifications by applying
organic nanoparticles from a water
dispersion
Dr. Dirk Stanssens
2. Topchim introduction
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- Established in 1996
- Offices + laboratories in Belgium and Brazil
- R&D mainly focused on paper and card board coatings
- 3 actual core-domains:
- Rheology and water retention
- Barrier coatings (ecological alternatives)
- Organic nano-pigments
- New development group started for non-paper applications
3. Market drivers
• Better performing products at competitive prices
• Growing awareness for more sustainable solutions
• Use of renewable materials
• Recycling of used materials
• Reduction of VOC
• Water as an environmentally friendly and save
solvent
• Cradle to cradle solutions
4. Topchim’s Nano-particles
• Development of organic nanoparticles
– Good interaction with other materials
– High surface area
– Tunable properties
– Water borne
– High solid content
– Without use of external surfactants
– High bio-renewability content
• Applicable on most substrates
• Approved for food contact
5. Technologies to produce organic nano-particles
1. Straight synthesis by chemical transformation of
SMA polymers
2. Precipitation on inorganic carriers
3. Core-shell nanoparticles; encapsulation of active
ingredients
6. Technology 1: Nanoparticle Synthesis
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SMA: Poly(styrene maleic anhydride) SMI: Poly(styrene maleimide)
Nanoparticle formation:
•d = 100 to 150 nm (not filled with oil)
= 30 to 50 nm (when filled with oil)
•Tg > 1900C
•Possibility to make the particles
non-thermoplastic
7. Technology 2: Hybrid systems: precipitation of
the nano-particles on inorganic carriers 7
Carriers: e.g. glass, kaolinite, CaCO3, delaminated talc, TiO2:
8. Technology 3: Nano-encapsulation
+oils or
waxes
SMA: Poly(styrene maleic anhydride) SMI: Poly(styrene maleimide)
• Imidization in presence of oils or waxes leads to nano-
particles that include the oils or waxes
• Resulting particles have a core shell structure
• Particles can contain up to 70% of oil
• The oil can contain active ingredients such as dyes, UV-
absorbers, optical brighteners, perfumes, biocides.
9. -Technical solution: tunability by SMA type
-Paper (Ra = 60 nm)
174.78 nm
-SMI 1 (Ra = 15 nm) -SMI 2 (Ra = 11 nm)
122.74 nm 55.73 nm
-2 µm x 2 µm
0.00 nm 0.00 nm 0.00 nm
-Clustering of particles -Homogeneous distribution
-(higher imidide content)
-Lotus leaf
surface
10. SMI coating: Chemical interactions
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Chemical interaction of SMI-nanoparticles with paper surface
Interaction of nanoparticles with cellulose fibers occurs through
hydrogen-bonds and provides good adhesion without need of further
binder components
SMI-1
SMI-2
Paper
Raman shift (cm-1)
Region 1000-1100 cm-1: C-O stretching of C-OH groups Cellulose structure
11. Mechanical Stability
Upon drying, the nano dispersed particles coagulate to clusters.
Cohesion between the particles and adhesion to the substrate are
quite strong. No nano-particles are released upon friction.
SMI before friction SMI after friction
(Ra = 15.3, Rt = 92 nm)
56.08 nm (Ra = 11.2, Rt = 86 nm)
80.10 nm
height
height
400nm 400nm
0.00 nm
0.00 nm
13. Hydrophobicity
Static contact angle measurements at different temperatures
uncoated paper
SMA-coated paper
Contact angle (°)
SMI-coated paper
SMI-coated paper
250°C
Time (s)
15. Obtained results for paper coating applications
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• Good print quality and paper strength with less
coating weight
• Replacing environmental unfriendly substances
used in paper and card board production:
- Fluorine based additives
- Wax emulsions
- Polyethylene
• Improved repulpability
16. Environmental solution
• Water based dispersion of 50-65% solids
– Without use of external surfactants
– High bio-renewability content (up to 70% vegetable oil)
• Recyclable and compostable alternative for wax and PE treated paper and
board
• Applicable on online coaters (economically attractive compared to cost for
off-line wax treatment or PE-extrusion)
• 100% repulpability
18. Applications
• Corrugated board and boxes for fruit and vegetables
• Frozen food packaging
• Beverage cups and food plates
• Precoat for siliconised paper
• Liquid packaging
• Meat, Poultry and Fish wrap
• Compostable waste packaging (home recycling)
• Pizza and fast food containers
• Sandwich packaging
20. Market cups
• 220 billion paper cups/year worldwide
• 58% North America
• Growing consumption in emerging markets
21. TopChim’s technology
• Coated cup stock
• No thermoplastic film (like PE or PLA)
• Standard sealing process
• Coating chemistry based on particles containing vegetable oil
• Competitive alternative for PE treatment
• Suitable for cold and hot drinks
22. Performances
• No leaking, even after 24 hours
• Tunable for cost efficiency
– Layer thickness can be chosen
• Condensation barrier; 2 gsm of coating layer sufficient
• Additional oleophobicity (e.g. pop-corn cups or salad bowls)
25. Process cup stock production
• Surface treatment immediately at cup stock production
• No off-line extrusion treatment
– Less transport
– Less energy
– Less waste
• Treated cup stock is repulpable (broke and waste)
• Higher flexibility on barrier layer weight
26. Process cup production
• Standard cup production machines
• Standard sealing processes
• Waste is repulpable
• Printable
27. Ecological advantages
• Reduced manufacturing process
– Less energy and waste
– Less transport
• Higher degree of recyclability and compostability
• Highly reduced dependency on mineral oil based materials
28. Potential non-paper applications
• Use of nano-pigments and nano-dispersions for a.o.:
– Cosmetics
– Fibers
– Inks
– Paints
• Focus on:
– Applying coatings that make substrates hydrophobic
– Nano-encapsulating of active ingredients (dyes, optical
brighteners, perfumes, sun screen,…)
• Market approach by co-operation with development partners
29. Textile industry: semi-permeable coatings
• Fully water-borne coatings
• Good adhesion to several textile substrates
• Transparent coatings with good water repellency
• Nano-particles have a high Tg and are not film
forming
• The coating layer keeps its porosity and its
breathability
30. Ink applications
• Water borne formulations, no external surfactants
• Encapsulated dyes behave as nano-pigments
• Upon drying ink shows water repellency
• Very stable dispersion of pigments in water
– Carbon black, carbon nanotubes
– Can be used for ink-jet ink applications
31. Conclusions
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The imidisation of poly(styrene-maleic anhydride) results in
SMI nanoparticles:
- of 100 to 150 nm diameter
- Tg = 190 – 220°C
- with good mechanical resistance
- high dispersion stability in water
- leading to favorable processing characteristics
- having high interaction with other materials
32. Conclusions
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The SMI nano-particles can be produced in the presence of
a carrier material andor in the presence of oils and waxes.
Furthermore, these oils or waxes can contain active
ingredients. Properties such as e.g. water repellency, color,
UV absorption, gloss can be tuned by choosing the
appropriate combination of raw materials.
Topchim is open for collaborations on specific projects with
clear market needs.