C E N T E R S O F E X C E L L E N C ECenter for the Study of Polymer Systems
manias @psu.edu
Tailored Polyolefin/layeredTailored Polyolefin/layered--silicate silicate Nanocomposites with Novel Functionalities Nanocomposites with Novel Functionalities
Nanotechnology at ton quantities?Nanotechnology at ton quantities?
Evangelos ManiasEvangelos ManiasMaterials Science & Engineering deptMaterials Science & Engineering dept
Polymer Nanostructures Lab / CSPSPolymer Nanostructures Lab / CSPS
[email protected]://zeus.plmsc.psu.edu/
NanocompositesNanocomposites
A Definition1:
Polymer Nanocomposites The proper incorporation of nanoscale inorganic fillers to polymer matrices, so as to achieve novel (non-bulk) properties and multifunctionality(molecular hybrids or genuine nanocomposites 1 ).
Or (more common approach) design concurrent property improvements across a selected set of properties (nanofilled composites 1 ).
Today’s focus:
Polyolefin/Clay Nanocomposites Thermomechanicalenhancements and antimicrobial functionality
1 E. Manias, Nature Materials 6, 9-11 (2007)
Property Enhancements due to nm FillersProperty Enhancements due to nm Fillers
Concurrent Property Changes (cf. the respective pure polymers):improved novel mechanical propertiesdramatically reduced gas permeabilityincreased thermal stabilityincreased fire resistance(environmentally friendly FR additives)
AND Maintainrecyclability flexibility, optical claritylight weight, processability
Examples of “requests” in applications:non-permeable (to gasses/liquids), but flexible and light-weightstiff, but tough and flexible (even for thin films)synergy with conventional-fillers, high-volume, …, cheap (!!)
(in high(in high--performance performance nanofillednanofilled composites)composites)
Achieved with:extremely low filler content (typ. 1-5 wt%)simultaneous and non-trivial improvement in many propertieston-scale quantities
starting particle: agglomerate
• several μm in size (5-20 μm)
• millions of individual plateletsmorelikely
The Challenge: Achieving MiscibilityThe Challenge: Achieving Miscibility
desired
Courtesy: RA Vaia, AFRL, 2oo4
Thermodynamic ArgumentsThermodynamic Arguments
Designing miscible nanocomposites
introduce favorable excess interactionsi.e. polymer-clay interactions better than
clay-surfactant interactions
( )( ) ( )
fillerinorganic,surfactantpolymer,:,
2with
2
jijiji
ABij
LWj
LWi
LWijAB
ijLWijij
−−++ −−=
−=+=
γγγγγ
γγγγγγ
Vaia & Giannelis, Macromolecules, 30, 7990 (1997)
0<− fillersurffillerpol γγ
Structure of nanocompositesStructure of nanocomposites
For naturally occurring fillers (e.g. montmorillonite clay)there coexist intercalated/exfoliated filler structures
TEM A: intercalated layersB: exfoliated/disordered E. Manias et al, Chem. Mater. 13, 3516 (2001)
2D fillers2D fillers
eg. shown: PP/mmt
Mechanical property changesMechanical property changes
0 2 4 6 8 10600
800
1000
1200neat PP / C18H37 -MMT (conv. filler)neat PP / C18H37 & C8H4F13 -MMT
Mod
ulus
(MP
a)
inorganic concentration φ (wt %)
INSTRON; thin film ASTM protocol
0 2 4 6 8 100
200
400
600
800
1000
neat PP / C18H37-MMT (conv. filler)neat PP / C18H37 & C8H4F13 -MMT
Bre
ak s
trai
n (%
)
inorganic concentration φ (wt %)
0 2 4 6 8 1010
15
20
25
30
35
neat PP / C18H37-MMT (conv. filler)neat PP / C18H37 & C8H4F13 -MMTYi
eld
Stre
ss (M
Pa)
inorganic concentration φ (wt %)
“General” changes:tensile modulus 60% increase (small changes in yield stress)(small changes in break strain)
functionalizedfunctionalized0.5%0.5% PP / organoPP / organo--mmtmmt
E. Manias et al, Chem. Mater. 13, 3516 (2001)
Other Thermomechanical PropertiesOther Thermomechanical Properties
0 2 4 6 8 10
110
120
130
140
150
160
PP/ f-mmt (melt) PP/ f-mmt (extr) PP/ 2C18M (extr)
HD
T (o C
)
φ (wt %)E. Manias et al, Chem. Mater. 13, 3516 (2001)
PP heat deflection temperature
Similar trends for:
apparent Tgscratch resistancesurface moduluscompressive G’…
functionalizedfunctionalized0.5%0.5% PP / organoPP / organo--mmtmmt
Polar groups added as a block to PPPolar groups added as a block to PP
A single end-group(appropriately selected) can drive high miscibility.
Tensile Modulus 60%HDT 30oC
Z-M. Wang, H. Nakajima, E. Manias , and T.C. Chung, Macromolecules 36, 8919 (2003)
500nm
H CH2 CH CH2 CH2 NH3
CH3n
endend--functionalized PP / organofunctionalized PP / organo--mmtmmt
Technology leased toMitsubishi, Japan
Tensile Modulus
(MPa)
Tensile Strength (MPa)
Elongation at break
(%) unfilled
(0% Clay)
306 (±15)
24 (±1)
324 (±11) unfilled-TS*
(0% Clay)
329 (± 5)
24 (±1)
291 (± 5)
3% Clay 587 (± 9) 23 (±1) 325 (±11) 6% Clay 825 (±17) 24 (±1) 396 (± 6)
met
hod
A
9% Clay 1120 (±25) 23 (±1) 295 (±23)
3% Clay 581 (±32) 22 (±1) 316 (±17) 6% Clay 842 (±33) 25 (±1) 400 (± 1)
met
hod
B
9% Clay 1106 (±66) 22 (±1) 294 (±13)
Mechanical property changes (LDPE)Mechanical property changes (LDPE)
Heat Deflection TemperatureHeat Deflection Temperature
HDT (oC)
Neat 64.5
3%-Clay 70.5
met
hod
A
9%-Clay 87.0
Neat 63.0
3%-Clay 68.1
met
hod
B
9%-Clay 84.3
E. Manias, J. Zhang, et al., Macromolecular Rapid Comm., 30, 17-23 (2009)
Origin of thermomechanical behaviorOrigin of thermomechanical behavior
30 40 50 60 70 80 90 100 110
0
50
100
150
200
250
300
LDPE film (control) 3% MMT (B, o.66 gauge) 3% MMT (A, o.66 gauge) 3% MMT (B, o.60 gauge) 3% MMT (A, o.60 gauge) 3% MMT (B, o.50 gauge) 3% MMT (A, o.50 gauge)
6% MMT (B, o.60 gauge) 6% MMT (A, o.60 gauge)
Stor
age
Mod
ulus
(G',
MPa
)
Temperature (0C)
Origin of thermomechanical behaviorOrigin of thermomechanical behavior1 10 100
400
600
800
1000
1200
1400
1600
1800
2000
2200
2400
2600
Sto
rage
Mod
ulus
(MP
a)
1 10 100 1 10 100
1 10 100
40 0C0 0C 20 0C-20 0C
F requency (H z)
1 10 100
50
100
150
200
250
300
350
400
450
500
1 10 100
100 0C80 0C60 0C
1 10 100
DMA vs. freq(torsion mode)
LDPE (black) 6% MMT (red) 3mm flex-bars
Barrier propertiesBarrier properties
0.0
0.2
0.4
0.6
0.8
1.0
0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4
Volume Fraction Silicate
Rel
ativ
e Pe
rmea
bilit
y
Nanocomposite(PCL Nanocomposites)
Conventionally filled systems
AB
Data adopted from Giannelis et al., 1994
Origins:path tortuosity
“General” Trend:(amorphous polymers)PDMS PU PUUPS Elastomers...(few semi-crystalline) PVA polyamides
PermeabilityPermeability--Structure RelationStructure Relation
R. Xu, E. Manias, A.J. Snyder & J. Runt Macromolecules, 34, 337-339 (2001)
0
0.005
0.01
0.015
0.02
0.025
0.03
0 200 400 600 800 1000 1200 1400
Extension (%)
PUU
0.3%
0.8%
2%
3.8%
5.9%vol% silicate
Microtensile die (ASTM D1708-93)
PUU Nanocomposites:PUU Nanocomposites:elastomeric character retainedelastomeric character retained
R. Xu, E. Manias, A.J. Snyder & J. Runt Macromolecules, 34, 337-339 (2001)
Still Highly Rubbery !!Still Highly Rubbery !!
barrier incr. bybarrier incr. by 500%500%modulus incr. modulus incr. 500%500%strength incr.strength incr. 400%400%
‘Tortuous Path’
Macromolecules 2001, 34, 9189
effective α alignment
PermeabilityPermeability--Structure RelationStructure Relation
Strategies to orient nanofillersStrategies to orient nanofillers
Sd = 0.8 @ mg systemsabove 20mg sample aligned
with 1500VAC for 10min @ AFRL
Sd = 0.6 @ kg/h systems
above at 50–150 lb/h two independent blow molding lines*
(2D nanoparticles)(2D nanoparticles)Electric-field AlignmentEpoxy/MMTEpoxy/MMT
Flow-induced AlignmentHDPE/MMTHDPE/MMT
* E. Manias, J. Zhang, MM Jimenez-Gasco, et al. Macrom. Rapid Comm., 30, 17-23 (2009)
100μm
Poly(ethylene oxide)Poly(ethylene oxide) PolypropylenePolypropylene syndiosyndio--PolystyrenePolystyrene
PEO/3 wt% mmtPEO/3 wt% mmt PP/3 wt% mmtPP/3 wt% mmt sPSsPS/3 wt% mmt/3 wt% mmt
Nanofillers and polymer crystal morphologyNanofillers and polymer crystal morphologynegative contributions to barrier performance
Antimicrobial ActivityAntimicrobial Activity
Our best performing* nanocomposites, which canbe/are used for flexible packaging, are based on commercial organo-nanofillers and are not antimicrobial
How can we design a nanofiller that affords antimicrobial activity?
Employ surfactants that are promoting dispersion andhave antimicrobial activity !
(in collaboration with Plant Pathology/PSU)
* High-barrier flexible films, Peelable heat-sealants, etcE. Manias, J. Zhang, MM Jimenez-Gasco, et al. Macrom. Rapid Comm., 30, 17-23 (2009)
J. Zhang, E. Manias, C.A. Wilkie, J. Nanoscience and Nanotechnology, 8, 1597 (2008)
Antimicrobial ActivityAntimicrobial Activity(in collaboration with Plant Pathology/PSU)
Polymer/Organo-Filler ActivityActivity retained even when organofillers are
encapsulated in polymer at very low loadings (3% and 6%)
Ponusa Songptiya, M.M. Jimenez–Gasco, E. Manias
Beyond Dispersion Control of Hierarchy of Structurese.g. alignment, house of cards, control at the μm scale, preferential dispersion in one phase or at the interphase
what can be done tomorrow…
PET
PC
Future Outlook: A Personal Perspective Future Outlook: A Personal Perspective
Design and Incorporate Multiple Desired FunctionalitiesAdded beyond barrier + stiffness, cf. antifouling, biodegradable, (di)electrical or radiation, heat-sealing, independently manipulate and tailor specific properties…
Design and Incorporate an Adaptive CharacterIncorporate responses to environmental or chemical changes (not just sensors, but ‘smart’ stimuli-responses)…
Bioinspired Nanostructured Polymers and CompositesHere the opportunities are almost limitless… Look at nature’s examples of structural materials, skins, structures with specific processes, and imagine if we could make synthetic equivalents of such systems/structures…
what can be in the near future…
what can be in the not-so-near future…
Future Outlook: A Personal Perspective Future Outlook: A Personal Perspective
Concluding RemarksConcluding Remarks
Nanotechnology is not nanobots or Star-Trek gadgets !!It can be a polymer nanocomposite that you may already use (e.g. medical/food packaging, automotive, construction,…).
Polymer/inorganic nanocomposites can afford high-impact real-life applications:(1) by affording substantial improvements in performance, overcome property trade-offs of conventional composites (cf.nanofilled polymers new materials, disruptive technologies).(2) by affording new and novel functionalities (cf. genuine nanocomposites transformative research, radically new materials & applications)
Polymer/Inorganic nanocomposites are a viable technology for many “new” materials for near-future structural applications.However, they are not the solution to all problems (!!!)
Collaborators:Collaborators:E. Giannelis (Cornell)
T.C. Chung (PSU)J. Runt (PSU)R. Krishnamoorti (UH)R. Vaia (AFRL)C. Wilkie (Marquette)M. Jimenez-Gasco (PSU)D. Macdonald (PSU)J. Genzer (NCSU) J. Floros (PSU)C. Randall (PSU)
Fuel-Cells:Zijie Lu Hungoo ChoA. Karatrantos Y. Chang
Grad. students:Grad. students:... Jie ChenKen StrawheckerZhiming WangVikram KuppaSung Woo WeeAlexei KisselevMatt HeideckerGreg HogsheadTheresa FoleyPonusa SongptiyaNgoh ManokruangRomesh Patel Financial Support:Financial Support:NIST NSF PDA DoE ONR AFOSR
Air Products UTC/IFC BAYER MATSCCoca-Cola Asahi-Kasei Arrow-BioMedSumitomo Chem PPG Samsung Kraft
Postdocs:Postdocs:Lixin Wu Yang JiangHiroyoshi NakajimaM. RackaitisS. ChowdhuryJin-Huh YoungGeorge PolizosJinguo ZhangK.S. Andrikopoulos
AcknowledgementsAcknowledgementsall cited papers (full-text) here:
http://zeus.plmsc.psu.edu/want a copy of the presentation?
[email protected] groupManias group
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