Nano Technology & Nano Materials by Ray Fernando, PHD California Polytechnic State University Polymers and Coatings Program Department of Chemistry and Biochemistry San Luis Obispo, CA www.polymerscoatings.calpoly.edu Delivered 22 June 2009 @ SLINTEC

1. Ray Fernando, PhD
Fernando
22 June 2009
California Polytechnic State University
Polymers and Coatings Program
Department of Chemistry and Biochemistry
San Luis Obispo, CA
p ,
www.polymerscoatings.calpoly.edu

4. Nanotechnology Overview
Nanomaterials Properties
Potential Benefits
Commercial Applications
Challenges

5. Nanotechnology is the understanding and
control of matter at dimensions of roughly 1
to 100 nanometers, where unique
phenomena enable novel applications….
……………encompassing nano-scale science,
engineering and t h l
i i d technology; nanotechnology
t h l
involves imaging, measuring, modeling, and
manipulating matter at this length scale
scale.
(www.nano.gov)

6. U.S. National Nanotechnology Initiative (NNI)
Initial phase funded by Federal Government in late
1990’s
Formal NNI proposal on March 11, 1999
Funded in 2001 with a$489 million
“…….a ‘new industrial revolution’ powered by
systematic control of matter at the nanoscale….”
y
NNI is largest nanotechnology investor
over last 7 years ($7 billion)
Now NNI involves 26 independent agencies $1.5
l d d $
billion (2008)
“Top ten advances in materials Science”, J. Wood, Materials Today, 1(12), 40

7. Global Initiatives
Over 65 countries have national research focus projects
on nanotechnology
2007 global nanotechnology related R&D budget was
g gy g
in excess of $12 billion
Industry investment surpassed governments’ in recent
years.
years
“Top ten advances in materials Science”, J. Wood, Materials Today, 1(12), 40

8. http://www.nano.gov/html/facts/The_scale_of_things.html

9. C-C bond – 1.5 angstroms
g
C-H bond – 1.1 angstroms
Ethanol: CH3-CH2OH
10-4 10-2 100 102 104 106 108 1010
Nanometer

10. Size and refractive index of particles are
important
Nanoparticles are smaller than the
wavelength of visible light; reduces chance of
light scattering

11. Polymer latex particle size 50 - 500 nm
Hiding
Hidi grade TiO2 particle
d ti l 200 - 250 nm
size
Polyurethane Dispersion 50 - 100 nm
particle size
Polymer molecular size in 2 - 100 nm
solution

12. A = 4Πr2

13. Volume = 4/3*π*r3 Surface area = 4*π*r2
1 gram of TiO2 Volume = 0.25 cm3
Particle
P ti l Particles
P ti l Surface
S f Surface
S f
diameter per gram area per Area /
(nm) gram (m2) Volume
200 6 x 1013 7.5 1.8 x 1012
20 6 x 1016 75 1 8 x 1016
1.8
2 6 x 1019 750 1.8 x 1020

14. Bulk properties are not scalable to nanoscale

15. A particle of 10nm diameter
has 20% surface atoms
A particle of 2nm diameter has
80% surface atoms
A particle of 1nm diameter has
ti l f 1 di t h
100% surface atoms
Single wall Carbon nanotube
A capped single-wall carbon nanotube with a slight bend.
http://www.thomas-swan.co.uk/pages/nano_images.html

16. Particle Diameter
(nm)
( ) 300 250 200 150 100 50
Interfacial 0.03 0.04 0.05 0.06 0.10 0.22
Volume Fraction
10 nm Interfacial Layer
Dispersed particle volume fraction is 0.3 in all cases

17. Extensive interfacial area
103 to 104 m2/ml
Large number density of particles
106 to 108 particles/μm3
Low percollation threshold
~0.1 – 2 volume%
Short d
Sh distance between particles
b l
~0.1 – 2 volume%
Bulk
B lk material properties not scalable
t i l ti t l bl
Optical clarity

18. Polymer molecules at i t f
P l l l t interface Surfactants t
S f t t at water/air i t f
t / i interface

19. “Thermo-mechanical properties of LLDPE/SiO2 nanocomposites”, E.
Kontou and M. Niaounsikis, Polymer, 47, 1267, 2006 - Tg
K t d M Ni iki P l 47 1267 T
increases of 25 to 30oC observed with up to 10% nano silica
“Glass-Transition Temperature Behavior of Alumina/PMMA
Glass Transition
Nanocomposites”, B. J. Ash, R. W. Siegel, and L. S. Schadler, J.
Polym. Sci.: Part B: Polym. Phys., 42, 4371, 2004. – Nano
alumina / PMMA composites. 25oC drop in Tg with less
p p g
than 1% 38nm and 0.5% 17 nm. Up to 10% further addition
did not lead to additional Tg reductions

20. “Glass Transition of the Polymer Microphase”, Bares, J.,
Macromolecules, 8, 244, 1975 - Tg of finely dispersed phases
(~12 nm) was 20oC lower than the analogous bulk phase;
proposed the first equation (modified Fox-Flory) relating the
Fox Flory)
Tg to the enhanced surface to volume ratio
“Nanofiller effect on the glass transition of a polyurethane”, J. G.-I.
Rodriguez, al., J.
Rodriguez et al J Thermal Anal Calorimetry, 87(1), 45, 2007 -
Anal. Calorimetry 87(1) 45
DSC study on polyester PU with “nano” silica. Silica
particle sizes are 175, 395, 730 nm, and levels are up to 10
wt.%; PU Tg ( oC) did not change with the nanoparticles
; g (-10 ) g p

22. y
“Dynamic and viscoelastic behavior of natural
rubber/layered silicate nanocomposites
obtained by melt blending”, Ramorino, et al.,
Polym. Eng Sci
Polym Eng. Sci., 2007
“Natural rubber nanocomposite reinforced
with nano silica”, Chen, et al., Polym. Eng. Sci.,
silica ,
2008
“Sol-gel process of alkyltriethoxysilane in latex
for alkylated silica formation in natural
rubber”, Siramanont, et al., Polym. Eng. Sci.,
2009

23. Dispersion of layered inorganics in polymer
In-situ generation of nano-phases
Incorporation of nano-particles

24. Nylon/Clay
Nanocomposites
(Toyota/Ube,
1980’s)
1980’ )
70% higher tensile
modulus
125% higher flexural
modulus
Heat distortion
H t di t ti
temperature
increased from 65 oC Epoxy / Layered Silicate (Vaia –
to
t 152 oC Materials Today, 2004)

25. X-ray diffraction pattern
Dispersed Intercalated Exfoliated
•Pinnavaia, T.J., and Beall and G.W. (Ed.), “Polymer-Clay Nanocomposites”, Wiley
(2000)
•Gao F Materials Today November 2004
F., Today,
•Vaia, R.A. and Wagner, H.D., Materials Today, November 2004

26. Barrier
Gas, Water etc
Gas Water, etc.
Anti-Corrosion
Fire Retardancy
Mechanical Properties
Microcomposite
Aspect Ratio
25:1
Nanocomposite
Aspect Ratio
250:1

27. Nano-Clay Suppliers
Elementis
Nanocor
Southern Clay
Others
Product Manufacturers
P d M f
Inmat, Inc.
2001 Wilson double core tennis balls
Recent efforts on PET, PP film barrier coatings
Others

28. TEOS Hydrolysis/condensation

30. Sol-
Sol-Gel Hybrid Nano-Composite
Nano-
Coatings
OCH3
TEOS H3CO
Si
OCH2CH2CHCH2 Cyclo-aliphatic Epoxy
OCH3
O
OC2H5
+ + O
H2
GPTMOS C C
Si O
C2H5O OC2H5 O O
OC2H5
Inorganic / Organic Nanocomposite
g g p

31. Aluminum Oxide Copper Oxide
Antimony Tin Oxide Indium Tin Oxide
Barium Sulfate Iron Oxide
Bismuth Oxide Nano-Clays
Boehmite POSS
Calcium Cabonate Silicon Dioxide
Carbon Nanotubes Titanium Dioxide
Cerium Oxide Zinc Oxide
Cobalt Aluminate ...……

32. Anti-microbial Optical Properties
Antistatic Photocatalysis
Gas/Stain Barrier Surface Energy
Corrosion Modification
Fire Retardant UV Stability
IR-Absorption X-Ray Shield
Magnetic ………..
Mechanical

33. 100
90
Gloss Retention (20 )
o
80
70
Alumina C
60
Alumina D
%G
50 Silica A
40
0 0.5
05 1 1.5
15 2 2.5
25 3 3.5
35
Nanoparticle Content (Wt.%)

35. Transformation of a Simple Plastic into a Superhydrophobic Surface
Erbil, Demirel, Avci, and Mert, Science, Vol 299, Issue 5611, 1377-1380 , 28 February 2
Figure 1. (A) The profile of a water drop on a smooth i-PP surface that has a
contact angle of 104° ± 2° Th i PP film was prepared by melting at 200°C
t t l f 2°. The i-PP fil db lti t
between two glass slides and crystallizing at 100°C. (B) The profile of a water
drop on a superhydrophobic i-PP coating on a glass slide that has a contact
angle of 160°. The i-PP was dissolved in a 60% p-xylene/40% MEK mixture by
volume at an initial concentration of 20 mg/ml at 100°C. The solvent mixture
was evaporated at 70°C in a vacuum oven The morphology of the i-PP coating
70 C oven.
is shown in Fig. 4.
Fig. 4. SEM picture of an i-
PP coating obtained using
the nonsolvent MEK as
described in Fig. 1B

36. θ
θ - Contact Angle
Zero Contact Angle
Spontaneous Wetting
& Spreading

37. Rainwater cleans lotus leaves
because of their bumpy surface.
Abramzon, et al., Chemistry & Life (1982)
y ( )
Barthlott et al., Annals of Botany (1997)

38. Nano-Structuring Methods
Nun, Oles, & Schleich, Macromol. Symp., 187, 677-682 (2002)
“Nanostructured superhydrophobic surfaces”, H. M. Shang, Y. Wang, K.
Takahashi, G. Z. Cao, D. Li, and Y. N. Xia, J. Mater. Sci., 40, 3587, 2005

39. 1.0 Wt. % Alumina D ~25nm Avg. 0.67 Wt. % Alumina C ~25 nm Avg.
particle size, 10 micron scan area particle size, 10 micron scan area

40. g
Self-cleaning surface
Antibacterial Activity
Super hydrophilicity
Anti fogging
Anti-fogging activity

41. 1.2
1
UV Visible Region IR
ce
0.8
08
Reflectanc
0.6
R
0.4
Rutile
Anatase
0.2
0
360 400 440 480 520 560 600 640 680 720
Wavelength (nm)
W l th ( )

42. TiO2 + UV light ⎯→ e- + hole+
e- + hole+ ⎯→ TiO2 + heat
hole+ + OH- ⎯→ OH•
e- + O ⎯→ O •
2
-
2
•
O2- + OH• + (-CH2-) ⎯→ intermediates
•
O2- + OH• + intermediates ⎯→ CO2 + H2O
UV light + O2 + (-CH2-) ⎯→ intermediates
→
UV light + intermediates ⎯→ CO2 + H2O
Self-Cleaning Surfaces

43. Chalking: loose pigment particles form on the surface from the
erosion of the binder as a result of photodegradation.
photodegradation
Type I Type II Type III Type IV
Anatase Rutile Rutile Rutile
Product Name LW R-900 R-900, R-901 R-960
TiO2 min %
min.% 94 92 80 80
Chalking free medium medium medium
resistant resistant resistant
Surface treatment none Al2O3 SiO2 +Al2O3 SiO2 +Al2O3
Complete encapsulation to protect TiO2 from UV free radical reaction

44. www.nanotechproject.org
www.nanoshop.com

45. Umicore – transparent Cerium Oxide and Zinc Oxide in Waterborne and
solvent-based PU coatings for wood.
Nanovations - Lignol® Wood Coating with nanoscale UV absorber; Nano-
Silver, antimicrobial and energy saving façade paint from Bioni Paints
“Bioni Paints are the only chemical free coatings in the world that can prevent
Bioni
the growth of moss, algae and mildew permanently”
Teak Guard® Marine with Nanotechnology UV protection
Nanotec Ultra® Coating UV protection
Nanolinx™ “First wood floors finishing system to use a network of crosslinked
g y
nanoparticles”
Nanoseal® Wood by Nanotec “…is not a sealer; nano particles adhere directly
to substrate molecules……hydrophobic surface”; Nanoprotect® AntiG is a
molecules hydrophobic surface ;
water based nanotechnology treatment that provides a layer against Graffiti on
concrete and natural stone surfaces

46. •Nichiha Fiber Cement - “Nichiha uses Nanotechnology to create self-
Nichiha self
cleaning fiber cement panels”
•Markilux – Awning fabric SNC (Swela Nano Clean); dirt and water repellant
•STO Lotusan® Self Cleaning Paint – water repellant surface
•AVM Industries – E-85 Nano 2000™ Self cleaning and deodorizing
Titanium Dioxide coatings – water based
based.
•Akzo Nobel – Herbol® brand for professional architectural paints and
coatings has introduced Symbiotec based on BASF’s COL.9 technology for
façade coatings. Water based, water-thinnable, easy to handle, less
thermoplastic, low dirt pick-up
•Behr – Nanoguard
Behr

47. •Nanoclean - supplier of ultrathin glass treatments
•NanoSafeguard - supplies photocatalytic self-cleaning hydrophilic
NanoSafeguard self cleaning
coatings for outdoor.
•Saint-Gobain Glass supplies BIOCLEAN for window glasses (UV
activated)
ti t d)
•Pilkington Activ™ Self Cleaning glass – nano thin layer
•Nanoprotect® Glass Coating by Nanotec – easy to clean; self-cleaning;
hydrophobic
•nanoCotz™ Eco Refresh and nanoCotz™
Eco-Refresh,
•Eco-Clean by Inspiraz, “The best self-cleaning clay roof in the world” by
Erlus, Germany
•n-tec, Germany – Photocatalytic Self-Cleaning Coatings – titania

48. •Centrosolar supplies glasses with or without nano-coated anti-reflective
properties
•Bioni Roof by Bioni – Heat reflecting roof coating with unique nano effects
Bioni,–
•Delphi Labs– “Asgard™ is comprised of a strong, ultra-thin, transparent
silica binder that holds tin-oxide and other functional ingredients in place
•NaturalNano – supply cell phone blocking paint based on nanotechnology
•Halloysite nanotubes 100nm X 500nm; claim that the tubes are inserted
Halloysite
with copper particles to reflect radio signel; other applications claimed as
well.

49. Nanoparticle Suppliers
Altair Nano
BYK-Chemie
Clariant
Degussa
g
Fuso Chemical Co.
Hybrid Plastics
Ishihara
Nanophase
Nanoscale Corp.
Sachtleben Chemie
Solvey
Sukgyung A.-T.
Sumitomo Osaka Cement Co
Co.
…..& many more

50. Carbon Nanotubes (CNTs)
Multiwalled
Sumio Iigima Nature 354 56 1991
Iigima, 354, 56,
Radushkevich and Lukyanovich, Zurn. Fisic. Chim., 26, 88,
1952
First direct observation reported
p
Oberlin et al.. J. Cryst. Growth, 32, 335, 1976
First image published
Single-walled
Iigima and Ichihashi, N t
Ii i d I hih hi Nature 363 603 1993
363, 603,
Bethune et al., Nature 363, 605, 1993
Nano-buds; Bucky-ball
Graphene
Calling all Chemists, Nanure Nanotechnology, 3, 10 January 2008
by Rod Ruoff UTexas
Recent report b P d’h
R t t by Prud’homme – F
Functionalized G h
ti li d Graphene N Nano-
Sheets. Tg of PMMA increased to 118C from 95C at 0.25 wt.%
level

51. Mechanical Properties
Light Weight
Conductivity
Metallic to Semiconductor

52. p
More than 50 companies worldwide
Aerospace Corp.
Applied Carbon Nanotechnologies
Arkema
Bayer Materials
Nanoledge
Canatu
Nanocyl
N l
ZYVEX Performance Materials
Hyperion
Ilgin Nanotech
Shenzhen Nanotech
Mitsui-Hodogaya

53. Dispersion and Dispersant Demand
Surface Functionalization
• Application Specific
Rheology
Aggregation & Flocculation
Characterization
Cost/Performance Balance
Health Safety
Health-Safety Concerns

54. BASF COL.9 Nano binder (Example)
Nano-binder
Herbol (Germany) Façade coating
Major US Paint Manufacturer
j
Low dirt pick-up and better durability claimed
Composition: Nano-silica embedded in polymer
latex particle d i synthesis
l i l during h i
Avoids dispersion by formulator
Minimum interference with polymer particle
coalescence

59. Characterization Techniques
For Bulk/Surface Morphology, Microstructure and Dispersion
Micro- (Meso-) Macro-
Nano
Nano-
nm μm mm
AFM
TEM - SEM Optical Microscopy
Laser Scanning Confocal Microscopy
Light Scattering
Neutron Scattering
SANS USANS Scattering
metrology
X-ray Scattering
SAXS/WAXS USAXS
Courtesy of LiPiin Sung - NIS

60. •Nanoscale Materials Stewardship Program – launched by EPA
January 28, 2008. TSCA Inventory Status of Nanoscale
Substances – Jeneral Approach 2008 pdf available at website
website,
•Epa.gov/oppt/nano/stewardship.stm
•“The potential risks of nanomaterials: a review carried out for
p
ECETOC”, P. J. A. Borm and 10 other authors, Particle and Fibre
Toxicology, 3(11), 2006. Open Access at Journal website.
ECETOC – European Centre for Ecotoxicology and Toxicology of
Chemicals - 35 page review with 172 references
•Nanosafe2.org

62. Volume / Mass:
y
Gravity
Volume
Vol me d3
Surface:
Friction
F i ti
Surface Energy
Van der Waals
Charge capacity
Surface
S f d2
10-9 10-8 10-7 10-6 10-5 10-4 10-3 10-2 10-1 100 101
meters

63. Dispersion and Dispersant Demand
d d
Rheology
Characterization
Material Safety/Health Effects
Cost/Performance Balance
*FSCT Virtual Learning Conference -- 2004

64. Theory
DLVO Th
(Two Particles)
S
Inter Particle
Inter-Particle Forces
a - Van der Waals, Long-range (Attractive)
b - Electrostatic, Long-range (Attractive or
Repulsive)
R l i )
c - Steric, Short-range (Repulsive)
g (
d - Solvation, Short-range (Attractive or
Repulsive)
e - Born, Atomic-range (Repulsive) 64

65. Repulsive
Potentia Energy
c
b
e S
al
d a
Attractive
Att ti
Repulsive
ergy
otential Ene
S
Flocculation/
Po
Aggregation Agglomeration
Attractive
65