Functional Polymers Challenging ChromatographyChromatography
Ryan Mondschein, Alison Schultz, Justin M. Si ine Ch istophe B Williams and Timoth ESirrine, Christopher B. Williams, and Timothy E.
Long
Virginia TechDepartment of
ChemistryChemistryMacromolecules and Interfaces Institute
Blacksburg, VA 24061 USA
MII DREAMS LaboratoryMII DREAMS Laboratory1 mm
Where is Virginia Tech? Macromolecules and Interfaces InstituteMacromolecules and Interfaces Institute
Washington D.C.g
Blacksburg,g,Home of Virginia Tech
Macromolecules and Interfaces Institute From Molecules to ManufacturingFrom Molecules to Manufacturing
Founded 1975, currently 120 graduate students, 30 faculty, MACR graduate degreeInternational ranking, top-national ranking of polymer programs
Additive manufacturing: A synergy of novel geometry with materials designgeometry with materials design
vsvs.
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4
http://upload.wikimedia.org/wikipedia/commons/6/68/Fotothek_df_n‐20_0000140_Zerspannungsfacharbeiter.jpg
Additive manufacturing: layer-by-layer (LbL) creation of physical 3D objects(LbL) creation of physical 3D objects
3D Printer3D CAD .STL Slicing 3DLayer Slices 3D Printer3D CAD Model
SFile
S c gSoftware
3D Object
Layer Slices and
Tool Path
3D printing advantageously allows:STL
3D printing advantageously allows:Customization of almost any objectHighly detailed objects with intricate geometriesDigital design and distribution of parts
(STereoLithography) is a file format native to the stereolithographyCAD ft t d Digital design and distribution of parts
Improved sustainabilityCAD software created
by 3D Systems.
Challenge, Opportunity, and InvitationAdditive manufacturing needs:
– Larger catalog of working materialsSt t P t P d t di– Structure-Property-Process understanding
Polymer chemistry opportunities:T il i h l / i it f AM– Tailoring rheology/viscosity for AM platforms with new macromolecular architectures
– Understanding intermolecular interactions at interfaces, surfaces, and interfacial phenomena
http://wohlersassociates.com/roadmap2009.html
phenomena– Physical properties of layered architectures– New orthogonal synthetic methods and
6
New orthogonal synthetic methods and photo-reactive monomers/oligomers
What are the advantages of phosphonium-based ILs and phosphonium ionomers?based ILs and phosphonium ionomers?
Ammonium PhosphoniumC tiCation Cation Nitrogen exhibits a partial negative charge
Phosphorus exhibits a partial positive charge
Does the cation structure influence macromolecular properties such as thermal stability and conductivity?
Does the cation structure impact coacervate formation with negatively p g ycharged macromolecules?
8
Aqueous SEC determined absolute molecular weights for all polyelectrolytesmolecular weights for all polyelectrolytes
M MPolymer dn/dc
(mL/g)
Mn(kg/mol)
Mw(kg/mol)
PDI
PTMA 0 203 225 311 1 38PTMA 0.203 225 311 1.38PTEA 0.179 251 395 1.57PTPA 0.197 167 238 1.43 0.80
1.00
nsit
y
PTBA 0.165 250 391 1.56PTMP 0.185 235 292 1.25PTEP 0 190 270 388 1 44
0.40
0.60
tive
Int
en
PTEAPTBAPTEPPTEP 0.190 270 388 1.44
PTPP 0.189 342 553 1.62PTBP 0.195 314 499 1.59 0.00
0.20
15 25
Rel
at PTEPPTBP
Aqueous SEC: 54/23/23 H2O/MeOH/AcOH 0.1M NaAcetate, MALLS 9
15 25Time (min)
RAFT polymerization created the desired phosphonium diblock copolymersphosphonium diblock copolymers
RAFT polymerizationRAFT polymerization successfully controlled the molecular weight
10
Anion exchange of phosphonium 4-vinylbenzyl trioctyl phosphonium chloride achieves a photo-curable ILcurable IL
Low Tm for TOPTf2N enables
5 eq LiTf2N
Acetone, 23 oC24 h
PCl PTf2NTOPClT (oC)
TOPTf2NT (oC)
2IL photocuring
Tm (oC) Tm (oC)87 < -90
hv
Mask projection micro-stereolithographyachieves well-defined 3D objectsachieves well defined 3D objectsSpecifications:Build Volume: 6 mm x 8 mm x 36 mmmm Resolution: 10-30 micronsLayer Thickness: 25 micronsBuild Rate: resin dependant
ComputerBuild Rate: resin dependant
Light Source Conditioning
OpticsMirror
PhotopolymerContainer
Linear Actuator
8 mm tall Hokie Bird
3D Printer: UV LED 365 nm, build surface intensity 5 mW/cm2, Digital micro image device 1080 p
C&E News, December 2014
X-Ray microCT reconstructs poly(PEGDMA90-co-TOPTf2N10) 3D cones to reveal reproducibility of CAD designs object
OO
x z
2D x-rayrotation
t
x-ray source
O
OO
PTf2N
MPµSL
2D x-ray detector
stageO
y
MicroCT: SkyScan 1172, 180O scan, 0.4O step
X-Ray microCTCAD Design MicroCT Image
SEM images of 3D hyperboloid reveals structural definitionstructural definition
0.5 mm1 mm
SEM: NEO Scope JCM 5000
Polyester cylinders provide structural advantages in tissue-engineered scaffolds
Inner layer:Endothelium
Middle layer:Smooth muscle & elastic tissue
Outer layer:Elastic and collagen fibers
llumen
SEM: NEO Scope JCM 5000
SFC-ELSD allows for high sensitivity oligomer separationoligomer separation
2 750 R
8 000
9.000
10.000
Range: 11Area
1.500
1.750
2.000
2.250
2.500
2.750
5.84922.57
7.58334.69
m=1
m=2
3
Species Molecular Weight (g/mol)
6.000
7.000
8.000
LSU
0.000
0.250
0.500
0.750
1.000
1.250
8.64150.88
9.3471.41
9.8539.05 10.20
31.86 10.6018.40
m=3m=0 495
m=1 2813Etc…
LSU
3.000
4.000
5.000
5.84
5.00 6.00 7.00 8.00 9.00 10.00 11.00
-0.250 m=2 5131
m=3 7450
m=4 9768
0.000
1.000
2.000922.57
7.58334.69 8.64
150.88 10.2031.86
m 4 9768
*Peaks assumed to be oligomers with increasing number of repeat units
Time-0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 20.00 22.00
0.000
17
Aquity UPC2 SFC-ELSD, in collaboration with Dr. Mehdi Ashraf-Khorassani
Swiderski, K. W. et. al. Ind. Eng. Chem. Res. 2004, 43, 6281-6284.
Initial polymerization attempt, but serendipitous cyclic ionic liquids formp y q
Formation of highly favored six-membered ring
Theoretical m/z: 425.1583 g/molExperimental m/z: 425 1564 / l
membered ring results in quantitative yields
N i ifi t 425.1564 g/molNo significant oligomerization
Hemp, S.T. et al. Polymer Chemistry 2013, 4(12), 3582-3590. 18
APC reveals the presence of cyclics in polycondensation reactionspolycondensation reactions
Column Set:450 Å x 150 mm 2 Low M
Scal
e
200 Å x 150 mm200 Å x 150 mm
2 Low MwPeaks
mal
ized
SN
orm
1 5 2 2 5 3 3 5 4 4 5 5 5 5 6
Waters® ACQUITY APC, RI Detector, THF, 1.0 mL/min flow rate, XT Columns 19
1.5 2 2.5 3 3.5 4 4.5 5 5.5 6
Time (min)
Altering column set to smaller pore sizes, low molecular weight peaks are resolvedlow molecular weight peaks are resolved
Column Set:450 Å x 150 mm
cale
200 Å x 150 mm45 Å x 150 mm
mal
ized
Sc
Nor
m 5 Low MwPeaks
1.5 2 2.5 3 3.5 4 4.5 5 5.5 6
Waters® ACQUITY APC, RI Detector, THF, 1.0 mL/min flow rate, XT Columns 20
Time (min)
Using smallest column set, low molecular weight peaks are fully resolved, possibly cyclicsp y , p y y
Column Set:45 Å x 150 mm
Å
cale
45 Å x 150 mm45 Å x 150 mm
aliz
ed S
c
5 Low Mw
Nor
m Peaks
1.5 2 2.5 3 3.5 4 4.5 5 5.5 6
Waters® ACQUITY APC, RI Detector, THF, 0.8 mL/min flow rate, XT Columns 21
Time (min)
Aqueous SEC elucidated the presence of oligomeric cyclics in certain compositionsoligomeric cyclics in certain compositions
2p,2-cyclic6p,4-ionene pre-dialysis6p 4-ionene post-dialysis
ensi
ty
6p,4 ionene post dialysis
ve R
I Int
eR
elat
iv
Aq. SEC RI, 54/23/23 H2O/MeOH/AcOH 0.1 M NaAc 22
20 22 24 26 28 30 32 34 36Elution Time (min)
Absolute molecular weights determined using aqueous SECusing aqueous SEC
Hemp, S. T.; Zhang, M.; Tamami, M.; Long, T.E. Polymer Chemistry 2013.y y
IoneneMn
(kg/mol)a
Mw
(kg/mol)a PDIbdn/dc
(mL/g)c Cyclics?b(kg/mol) (kg/mol) ( /g)
4P,4 17.9 24.0 2.36 0.225 Yes (10 ring)
4P,6 15.3 18.2 2.34 0.224 Yes (12 ring)
6P,4 16.1 18.6 2.00 0.224 Yes (12 ring)
6P,6 20.6 27.2 2.51 0.213 No (14 ring)
2P 12 10 7 12 4 1 84 0 210 No (16 ring)2P,12 10.7 12.4 1.84 0.210 No (16 ring)
4P,12 23.6 28.4 2.07 0.205 No (18 ring)
6P,12 15.3 19.6 2.05 0.201 No (20 ring)
aAq. SEC MALLS, 54/23/23 H2O/MeOH/AcOH 0.1 M NaAc; bAq. SEC RI, Relative 23
12P,12 18.8 19.5 1.31 0.191 No (26 ring)
Molecular weight increased during phosphonium ionene polymerizationphosphonium ionene polymerization
115 min30 min
0 6
0.8
Inte
nsity 45 min
60 min90 min
Increasing molecular weight with time
0 4
0.6
aliz
ed L
S I
120 min180 min240 min360 i
0.2
0.4
Nor
ma 360 min
480 min1440 min
022 24 26 28 30 32 34 36
Aq. SEC MALLS, 54/23/23 H2O/MeOH/AcOH 0.1 M NaAc
22 24 26 28 30 32 34 36Elution time (min)
Kinetic analysis confirmed expected step-growth kinetics for phosphonium ionenesgrowth kinetics for phosphonium ionenes
Recall Xn = 1/1‐p
Aq. SEC MALLS, 54/23/23 H2O/MeOH/AcOH 0.1 M NaAc 25
Hemp, S. T.; Zhang, M.; Tamami, M.; Long, T.E. Polymer Chemistry 2013.
Acknowledgments Dr. Chris Williams and the DREAMS Lab for collaboration with 3D printing Dr. Mehdi Ashraf-Khorassani for his help with UPC2 SFC-ELSD
Thank you for Your Attention!Thank you for Your Attention!