Coating Technology and Encapsulation – Closely

Titel van de presentatie
14-11-2014 10:52
Coating Technology and Encapsulation –
Closely Connected
dr. ir. Nicole Papen-Botterhuis, Scientist
TNO Materials Solutions
Eindhoven
Nicole Papen-Botterhuis
TNO Encapsulation Team
Encapsulation Technologies – Characteristics
barrier
barrier
release
release
Core-shell
Matrix
release
Sandwich
High performance materials as well as processing technologies are
required to meet the product demands
Properties:
Size (macro, micro, nano)
Size distribution (monodisperse, polydisperse, bimodal)
Morphology (matrix, core-shell, multicore-shell, double walled, sandwich)
Loading efficiency (maximize active vs. encapsulation material)
Encapsulation efficiency (minimize loss of active material)
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Titel van de presentatie
14-11-2014 10:52
Nicole Papen-Botterhuis
TNO Encapsulation Team
Encapsulation – Why?
Protect ingredients
(against oxygen, water)
Separate components,
prevent interaction
Delayed/slow: Prevent
burst release / premature
leaching (drugs, nutrients
antimicrobials, fertilizers)
Triggered: pH, water,
temperature, enzymes,
pressure/force
Keep
outside
out
Keep
ingredient
inside
Easy & safe handling (solid vs.
liquid, decreased volatility)
Enzyme immobilization
Taste masking
Biocompatibility
Controlled
release
Adjust
properties
Change physical properties
(solubility, structure, density)
Flowability
Hygroscopic control
Microencapsulation can bring you new products, new functionalities,
better product properties, higher added value – if done right
Nicole Papen-Botterhuis
TNO Encapsulation Team
Coating Technology and Encapsulation –
Closely Connected?
Encapsulation is in fact the coating of particles at the micro/nanoscale
Different processes/materials
What can we learn from each other?
Capsules can be applied in coatings to obtain an added value or
functional coatings
Isolation
Self-healing
Controlled release of active ingredients such as biocides
Stabilization of pigments
Sometimes added value can also we obtained without capsules, if the
barrier value of the coating itself can be adjusted.
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Titel van de presentatie
14-11-2014 10:52
Nicole Papen-Botterhuis
TNO Encapsulation Team
Development of encapsulation technologies
BASE TECHNOLOGY
Year
ADDITION
Controlled Release
Spray Drying of Solids
1872
Emulsified Oils, 1925,
Special Disk, 1949,1987
Spray Dried Flavors,
Reservoir Structure
Extrusion of Synthetic
Fibers into a bath
1920
Flavor Oils, 1957
Sunkist Process
Fluid Bed Drying
Top, Side, Bottom Spray
Nozzle & Partition 1965
Wurster Coating,
Agglomerization
Emulsion polymerization
Add Oil to Polymer
APS Polytrap
Spun Sugar (Cotton Candy)
Emulsify Oil into Hotmelt
Fuisz 1991
Droplet Stabilization With
Surfactants
Form a Massive Wall
Coacervation 1951
Parylene Coating
Tumbling of Powder
Parylene μE 1983
Polycondensation of Nylon
>1930’s Water Medium
Interfacial
Polymerization
U/F Resins
<1920
Polymethyleneurea, U/F
Pan Coating
19th
Specialty Coating, e.g.
Century enteric, “tunnel coating”
Coacervation Formation
Enhanced Release,
continuous process
Ronald Versic, RT Dodge Company, USA
Nicole Papen-Botterhuis
TNO Encapsulation Team
Ron Neufeld, Queen’s University, Canada
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Titel van de presentatie
14-11-2014 10:52
Nicole Papen-Botterhuis
TNO Encapsulation Team
Common microencapsulation technologies
Technology
Matrix or
Core-shell?
Size
(distribution)
Cost
Production
Use
Spray drying
large variations
2 - 100 µm
low
continuous
+++
Spray chilling
20- 200µm
low
continuous
+++
Extrusion
> 50 µm
low
continuous
++
Pan coating
>500 µm
low
batchwise
++
Fluidized bed
>50 µm
medium
batchwise
/continuous
++
Coacervation
1 - 500 µm
high
batchwise
++
Interfacial/ in situ
polymerization
1 - 500 µm
high
batchwise
+
Nicole Papen-Botterhuis
TNO Encapsulation Team
LOW
COST
HIGH
COST
Adjusted from www.SWRI.org
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Titel van de presentatie
14-11-2014 10:52
Nicole Papen-Botterhuis
TNO Encapsulation Team
Spray-drying
Widely used in food industry, e.g. to:
convert liquids into powders
protect flavour oils or other ingredients against degradation
Typically aqueous formulations of shell / matrix material
Ingredient either dissolved in matrix or present as emulsion (multi-core)
Advantages:
(Possible) Disadvantages:
+
+
+
+
− incomplete encapsulation
− mix of particle sizes
cheap, flexible process
continuous process
high throughput
small particles possible
Nicole Papen-Botterhuis
TNO Encapsulation Team
New TNO technology: printing-drying
Alternative to spray drying
Droplet generation by inkjet technology
viscosity upto 500 mPa·s
printing
low shear
droplet size ~50 to 120 m
droplet size variation <1%
100 L/h using multiple nozzle head
Advantages:
(Possible) Disadvantages:
+
+
+
+
− incomplete encapsulation
Energy saving
monodisperse
drops
drying
Continuous process
Monodisperse powders, no fines
High density powders
monodisperse
powders
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Titel van de presentatie
14-11-2014 10:52
Nicole Papen-Botterhuis
TNO Encapsulation Team
Methods for droplet extrusion
Dropping
Vibration / coaxial air flow (Nisco)
Vibration / electrostatic (Büchi)
Lists are not exhaustive!
Jet cutter (Genialab)
Rotating extruder (SWRI, Sprai, PCT)
Multiple nozzles (Inotech, Brace, TNO)
From R. Neufeld, Queen’s University
Nicole Papen-Botterhuis
TNO Encapsulation Team
Encapsulation by fluidized bed coating
+ Suitable for a wide range of shell materials
+ Tuneable shell thickness
- Only for solid core materials
- Standard not suitable for particles < 50 µm
- Moderate pay-loads, especially for small particles
- Polydisperse products, agglomeration during coating
Typical (food) ingredients: vitamins, minerals, leavening agents
Also used for much larger food components (flakes, grains)
Also used for pharmaceutical & cosmetic applications
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Titel van de presentatie
14-11-2014 10:52
Nicole Papen-Botterhuis
TNO Encapsulation Team
Encapsulation by (complex) coacervation
Phase separation of one or more hydrocolloids by changing pH,
salt concentration, etc.
+ High payloads possible
+ Good core-shell morphology
- Expensive & complex (batch) process
- Limited choice in shell materials
- Polydisperse capsules
Typical ingredients: flavour oils, also fish oil, vitamins etc.
Typical application areas of flavour microcapsules:
chewing gum, toothpaste, baked foods
Release mechanisms: sustained, mechanical or heat trigger
Nicole Papen-Botterhuis
TNO Encapsulation Team
Core-shell particles by co-extrusion
piezoelectric
vibrating unit
core liquid
shell liquid
Non-solvent stream (optional)
Concentric nozzle to process core & shell material
Collection in non-solvent or coacervation bath
Advantages:
+ narrow size distribution
+ high payloads possible
+ good core-shell morphology
(Possible) Disadvantages:
− no dry powders
− large size (w.o. non-solvent)
− interaction between core & shell
material may occur at the nozzle
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Titel van de presentatie
14-11-2014 10:52
Nicole Papen-Botterhuis
TNO Encapsulation Team
Core-shell particles by encapsulation printing
New processing technology for microencapsulation:
Generate core droplet by inkjet technology
Encapsulation by a liquid film / curtain of shell material
Nicole Papen-Botterhuis
TNO Encapsulation Team
Example: Encapsulation of oil droplets
aqueous solution of carrageenan and/or gelatin
oil droplets
gelation
by cooling
Core: 82 – 86 %
mechanical
release
shell = 5 – 8 m
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Titel van de presentatie
14-11-2014 10:52
Nicole Papen-Botterhuis
TNO Encapsulation Team
Example: Encapsulation of water-soluble core
aqueous core droplets
(with model dye)
molten
shell material
solid microcapsules
with waxy shell
capsule diameter 400 µm
solidification
by cooling
capsule diameter 70 µm
Size depends on parameters: flow rate, frequency, nozzle diameter
Nicole Papen-Botterhuis
TNO Encapsulation Team
Tuning shell thickness / core-shell ratio
Shell thickness depends on flow rate of liquid film:
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Titel van de presentatie
14-11-2014 10:52
Nicole Papen-Botterhuis
TNO Encapsulation Team
Advantages & challenges encapsulation printer
+ High payloads
+ Continuous process
+ Suitable for wide range of materials (aqueous, oils/waxes, polymers,
solutions, dispersions)
+ High viscosities & temperatures possible
+ Mild process conditions (low T, shear) possible
+ Separate conditions for core & shell materials
+ Well-defined, homogeneous product properties
- No recycling of shell material yet
- Early stage development
Nicole Papen-Botterhuis
TNO Encapsulation Team
Characteristics of encapsulation processes
load (%)
90%
core-shell
matrix type
sandwich type
complex
coacervation
70%
encapsulation
printer
fluidized bed
simple
coacervation
50%
spray drying
30%
… or print-drying
clay Intercalation
spray chilling
10%
1 µm
10 µm
100 µm
concentric
nozzle
melt
extrusion
1 mm
particle diameter
Information adapted from: Zuidam et al, Encapsulation Technologies for Active Food Ingredients and Food Processing, 2010
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Titel van de presentatie
14-11-2014 10:52
Nicole Papen-Botterhuis
TNO Encapsulation Team
Application Markets
Pharmaceuticals / Medical/ Animal Healthcare
Food / Nutraceuticals
Feed
Personal Care / Cosmetics
Home Care
Consumer Products
Agriculture / Aquaculture
Building materials / Paints & Coatings
Oil & Gas
Textiles
Energy storage
Skip examples
Nicole Papen-Botterhuis
TNO Encapsulation Team
Pharmaceuticals / Medical / Animal Healthcare
Sustained release (less pills, therapeutic window, from pills to implants)
Targeted release
Taste masking
Enteric release (protection against stomach)
Improved bioavailability
Animal/human cells (islets of Langerhans)
LCTglobal.com
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Titel van de presentatie
14-11-2014 10:52
Nicole Papen-Botterhuis
TNO Encapsulation Team
Encapsulation for Food Innovations
Flavors & Fragrances (aroma)
Immobilization during processing
Edible oils (omega-fatty acids)
Microorganisms (probiotics)
Levening agents
Vitamins
Shelf-life
Taste masking
Enteric release
Bioavailability
Quick dissolving powder
Free-flowing sugar
In situ generation of bactericides
Nicole Papen-Botterhuis
TNO Encapsulation Team
Personal Care/Cosmetics
Controlled release of fragrances: perfume, deodorant
Stabilization / Shelf-life
Bioavailability
Control of odour
Liquid to solid conversion
Cosmeto-textiles
Appearance
Marketing
Pelletech
Robert Blondel
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Titel van de presentatie
14-11-2014 10:52
Nicole Papen-Botterhuis
TNO Encapsulation Team
Home care / Consumer goods
Detergents (enzymes)
Adhesives
Controlled release fragrance
Masking odour
Shelf-life
Self-healing
Scratch ‘n sniff
Visual indicators
Liquid crystal displays
Liquid to solid conversion
Nicole Papen-Botterhuis
TNO Encapsulation Team
Agriculture/Aquaculture
Herbicides/pesticides
Handling & Safety
Fertilizers
Pheromones
Plant growth promoting bacteria
Food supplementation
Structuring fish food
Bioavailability
Ingredient stabilization
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Titel van de presentatie
14-11-2014 10:52
Nicole Papen-Botterhuis
TNO Encapsulation Team
Chemical Industry
Lubricants
Adhesives (pressure-sensitive glue)
Enzymes
Inks/pigments
Flavors/Fragrances
Thermochromic dyes
Fermentative production of ethanol, biogas, lactic acid (microorganisms)
Aid in processing: Immobilization, easy to separate
Chemicals for Enhanced Oil Recovery
Phase Change Materials (PCMs) for textiles and energy storage
Nicole Papen-Botterhuis
TNO Encapsulation Team
Building Materials / Paints & Coatings
Controlled release biocide coatings
Pigments
Self-healing coatings
Phase change materials
Antimicrobial coatings
Thermochemical storage
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Titel van de presentatie
14-11-2014 10:52
Nicole Papen-Botterhuis
TNO Encapsulation Team
Nanoencapsulation
Why?
Optical clarity (drinks, motor oil)
Better surface interactions
Stability of suspensions
Higher penetration depth/uptake (cosmoceuticals, cell therapy)
How? Liposomes, micelles, molecular entrapment, nanoclay
Challenges:
Loading efficiency is a challenge for core-shell particles
Very thin shells needed: ALD, CVD techniques?
Fragility of capsules
Use of large amounts of surfactants for nanoemulsions
Nanopowders not easy to handle (nanotox, flowability)
Nicole Papen-Botterhuis
TNO Encapsulation Team
Conclusions
Encapsulation can provide a solution to enhance products
There are many encapsulation technologies and materials
Encapsulation process should be designed to meet exactly the product
requirements: ask a specialist if you are new in the field
Encapsulation is used in many application areas
Challenges
Better barrier materials/layers
Smaller particles with high loading
Milder encapsulation processes
Biobased encapsulation materials
Overcome regulations
Low-cost solutions
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Titel van de presentatie
14-11-2014 10:52
Smart release of biocides in finishing materials for
the sector of construction
The EU project “Axioma”
‘To develop, adapt and apply smart release concepts of
eco-acceptable bio-inhibitors to extend service life of
finishing materials substantially.’
Moulds
Algae
Axioma why?
• Short bio-resistance of materials leads to early
replacement
• Environmental legislation restricts use of biocides
and chemicals
(Biocidal product directive 98/08/EC)
(Biocidal Product Regulation EU 528/2012, 1st Sept 2013)
Nicole Papen-Botterhuis
TNO Encapsulation Team
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14/11/2014
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Titel van de presentatie
14-11-2014 10:52
Modified inorganic particles
1.
2.
3.
swelling in a solvent (water)
cation exchange (modifier)
filtration + drying (de-swelling)
Possibility to load cationic
compounds onto clays, or anionic
compounds onto layered double
hydroxides.
Charge interactions can also take
place with neutral molecules (e.g.
amines).
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Nicole Papen-Botterhuis
TNO Encapsulation Team
Change of equilibrium
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Eversdijk, J., et al (2012). Development and evaluation of a biocide release system for prolonged antifungal activity
in finishing materials. Progress in Organic Coatings, 74(4), 640-644.
Nicole Papen-Botterhuis
TNO Encapsulation Team
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Titel van de presentatie
14-11-2014 10:52
Sample preparation
Loaded nanoclay
Rain setup
Coating
Biological and chemical tests
Nicole Papen-Botterhuis
TNO Encapsulation Team
Results paint
Improvement obtained by biological testing
Nicole Papen-Botterhuis
TNO Encapsulation Team
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Titel van de presentatie
14-11-2014 10:52
Results from gypsum
Artificial rain tests and Fungal growth tests
1. free biocide (red)
2. bound biocide with 100 wt%
hydrophobic modifier (blue)
With Clay
Without Clay
Fungal growth
5 times performance improvement
Nicole Papen-Botterhuis
TNO Encapsulation Team
Nicole Papen-Botterhuis
TNO Encapsulation Team
Conclusion
Coating Technology and Encapsulation –
Closely Connected!
Encapsulation
coatings
can be applied to improve the functionality of
Coatings
capsules
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Titel van de presentatie
14-11-2014 10:52
Nicole Papen-Botterhuis
TNO Encapsulation Team
TNO: Netherlands Organisation for Applied Scientific Research
TNO connects people and knowledge to create
•
innovations that boost the sustainable competitive
strength of industry and well-being of society
•
•
Den Helder
Groningen
Soesterberg
Hoofddorp
Leiden
Rijswijk
Enschede
The Hague
Apeldoorn
Helmond
Delft
Utrecht
Zeist
Eindhoven
Independent Dutch nonprofit
research institute
Approximately 3500 FTE
TNO Encapsulation team
– 9 FTE core + 20 part-time
– New encapsulation processes
– New encapsulation materials
For more information please contact:
Nicole Papen-Botterhuis M.Sc., Ph.D.
TNO
Dept. Materials Solutions
PO Box 6235
5600 HE Eindhoven
The Netherlands
[email protected]
+31 88 866 6234
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