The Effect of Additive Cyclic Blends on Linear Block...
1
0.6 0.65 0.7 0.75 0.8 0.85 0.9 0.95 1 1.05 1.1 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 d/d 0 Φ Cyclic Series1 Series2 Series3 4 4.5 5 5.5 6 6.5 7 7.5 8 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Domain Spacing Φ Cyclic Linear N=12 and Cyclic N=24 at Different χ Values Series1 Series2 Pure Linear 1. M.W. Matsen, Macromolecules, 2012. 2. M.G. Buonomenna, et. al. RSC Adv., 2012. 3. C. M. Bates, et. al., Macromolecules, 2013. 4.C. Tang, C.J. Hawker, et. al. Science, 2008. 5.R.D. Groot and P.B. Warren, J. Chem. Phys., 1997 The Effect of Additive Cyclic Blends on Linear Block Copolymer Domain Spacing Maxwell Rick 1 , Jessie Troxler 2 , Amy D. Goodson 2 , Julie N. L. Albert 2 , and Henry S. Ashbaugh 2 1 Benjamin Franklin High School, 2 Tulane University Abstract Acknowledgements Thank you to the Albert Group and the Ashbaugh Group We thank the National Science Foundation for financial support through grants DMR-1460637 and IIA-1430280, and the Graduate Research Fellowship Program (ADG). Conclusions and Future Work • Blending cyclic block copolymers into their linear analogues reduces domain spacing linearly. • Blending ordered cyclic block copolymers into disordered linear block copolymers can result in ordered systems. This represents a way to reduce domain spacing, as lower χ values and chain lengths correspond to lower domain spacing but may be below the ODT. • More simulations of different χ values and chain lengths will be carried out to further test the effectiveness of cyclic-linear blends to induce order. • Ultimately, thin film simulations are necessary, as nanolithography uses thin films (these simulations are in the bulk, but should not have crucial differences to thin film simulations). Cylinder simulations (see figure 1a) are another future possibility, as cylinders are also used for nanolithography. Dissipative Particle Dynamics Cyclic-Linear Blend Domain Spacing . Order-Disorder Transition (ODT) Figure 1: Based on chain length and composition, block copolymers self assemble into nanoscale morphologies (a) 1,2 which have a variety of applications. This work focuses on the lamellar (banded) morphology (a) 1,2 Cyclic BCPs (b) form features 20-40% smaller than their linear analogues. Figure 4: Coarse graining allows DPD to simulate large systems over long periods of time 5 . Application - Block copolymers can be used for nanolithography. For the required scale, the width of the lamellar bands (feature size) must be as small as possible. One interesting way to reduce domain spacing is to use cyclic block copolymers instead of linear ones. - Cyclic block copolymers are much more difficult to synthesize than linear ones. - This research uses simulation to test the effectiveness of using cyclic block copolymer as an additive into linear block copolymers of similar composition to reduce domain spacing. - The order-disorder transition is the point (χN value) where a block copolymer transitions from a disordered state to an ordered one (see figure 1a). - Low χN values correspond to lower domain spacing but may be below the ODT. - Adding small amounts of ordered cyclic block copolymers to disordered linear block copolymers may induce order. Pure Linear N=12 10% Cyclic Blend 25% Cyclic Blend Pure Cyclic N=24 Figure 7: At chain lengths N=8, N=12, and N=16, the normalized (divided by their respective pure linear domain spacing) domain spacing has a strong linear relationship with percent cyclic BCP in the blend. For each simulation, a=65. a=35 (low χ) a=65 (high χ) Figure 9: Comparison of blends of Linear N=12 and Cyclic N=24 (which have similar pure domain spacings) at different χ values. At the lower χ value, ordered cyclic block copolymers are blended into disordered linear block copolymers. At the higher χ value, both linear and cyclic are ordered. The lower χ value results in lower domain spacing. Domain spacings are only measured for ordered systems. Block Copolymer Self Assembly Figure 2 3 : A lamellar block copolymer with one polymer type removed Figure 3 4 : The process of block copolymer nanolithography 0.0 0.5 1.0 1.5 2.0 2.5 0 2 4 6 8 10 g(r) r d Figure 5: Domain Spacings are measured using radial distribution functions. Figure 6: Visual Molecular Dynamics (VMD) is used to generate snapshots of the simulated polymers. Analysis Methods Pure Cyclic N=8 N=12 N=16 a) b) Pure Cyclic d 0 N=16 Pure Linear d 0 Pure Linear Block copolymers (BCPs) can be used as templates for nanolithography. Advancing technology demands smaller lithographic features. Cyclic BCPs have smaller features than their linear analogues but are difficult to synthesize in high purity. We use DPD simulation to investigate the potential of cyclic BCPs as an additive to shrink domain spacing of linear BCPs. We have found a strong linear relationship between cyclic content and reduced domain spacing. Additionally, adding an ordered cyclic BCP can induce order in an otherwise disordered linear BCP. This approach may allow for further shrinking of domain spacing, as lowering the parameters χ and N results in smaller features but potentially disordered systems. S C G L Figure 8: Blends of linear N=12 + cyclic N=24 at a=35 (low χ) show a transition from disorder to lamellar between 10% cyclic and 25% cyclic. r dr References Linear N=12 Cyclic N=24 Pure Cyclic
Transcript of The Effect of Additive Cyclic Blends on Linear Block...
0.6
0.65
0.7
0.75
0.8
0.85
0.9
0.95
1
1.05
1.1
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
d/d 0
ΦCyclic
Series1Series2Series3
4
4.5
5
5.5
6
6.5
7
7.5
8
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
DomainSpacing
ΦCyclic
LinearN=12andCyclicN=24atDifferentχ Values
Series1Series2
PureLinear
1. M.W.Matsen,Macromolecules,2012.2. M.G.Buonomenna,et.al.RSCAdv.,2012.3.C.M.Bates,et.al.,Macromolecules,2013.4.C.Tang,C.J.Hawker,et.al.Science, 2008.
5.R.D.GrootandP.B.Warren,J.Chem.Phys., 1997
The Effect of Additive Cyclic Blends on Linear Block Copolymer Domain Spacing Maxwell Rick1, Jessie Troxler2, Amy D. Goodson2, Julie N. L. Albert2, and Henry S. Ashbaugh21Benjamin Franklin High School, 2Tulane University
Abstract
AcknowledgementsThankyoutotheAlbertGroupandtheAshbaughGroupWethanktheNationalScienceFoundationforfinancialsupportthroughgrantsDMR-1460637andIIA-1430280,andtheGraduateResearchFellowshipProgram(ADG).
ConclusionsandFutureWork• Blendingcyclicblockcopolymersintotheirlinearanaloguesreducesdomain
spacinglinearly.• Blendingorderedcyclicblockcopolymersintodisorderedlinearblock
copolymerscanresultinorderedsystems.Thisrepresentsawaytoreducedomainspacing,aslowerχ valuesandchainlengthscorrespondtolowerdomainspacingbutmaybebelowtheODT.
• Moresimulationsofdifferentχ valuesandchainlengthswillbecarriedouttofurthertesttheeffectivenessofcyclic-linearblendstoinduceorder.
• Ultimately,thinfilmsimulationsarenecessary,asnanolithographyusesthinfilms(thesesimulationsareinthebulk,butshouldnothavecrucialdifferencestothinfilmsimulations).Cylindersimulations(seefigure1a)areanotherfuturepossibility,ascylindersarealsousedfornanolithography.
DissipativeParticleDynamics
Cyclic-LinearBlendDomainSpacing
. Order-DisorderTransition(ODT)
Figure1:Basedonchainlengthandcomposition,blockcopolymersselfassembleintonanoscalemorphologies(a)1,2 whichhaveavarietyofapplications.Thisworkfocusesonthelamellar(banded)morphology(a)1,2CyclicBCPs(b)formfeatures20-40%smallerthantheirlinearanalogues.
Figure4:CoarsegrainingallowsDPDtosimulatelargesystemsoverlongperiodsoftime5.
Application- Blockcopolymerscanbeusedfornanolithography.Fortherequiredscale,
thewidthofthelamellarbands(featuresize)mustbeassmallaspossible.Oneinterestingwaytoreducedomainspacingistousecyclicblockcopolymers insteadoflinearones.
- Cyclicblockcopolymersaremuchmoredifficulttosynthesizethanlinearones.- Thisresearchusessimulationtotesttheeffectivenessofusingcyclicblock
copolymerasanadditiveintolinearblockcopolymersofsimilarcompositiontoreducedomainspacing.
- Theorder-disordertransitionisthepoint(χNvalue)whereablockcopolymertransitionsfromadisorderedstatetoanorderedone(seefigure1a).
- LowχNvaluescorrespondtolowerdomainspacingbutmaybebelowtheODT.
- Addingsmallamountsoforderedcyclicblockcopolymerstodisorderedlinearblockcopolymersmayinduceorder.
PureLinearN=12 10%CyclicBlend25%CyclicBlendPureCyclicN=24
Figure7:AtchainlengthsN=8,N=12,andN=16,thenormalized(dividedbytheirrespectivepurelineardomainspacing)domainspacinghasastronglinearrelationshipwithpercentcyclicBCPintheblend.Foreachsimulation,a=65.
a=35(lowχ)
a=65(highχ)
Figure9:ComparisonofblendsofLinearN=12andCyclicN=24(whichhavesimilarpuredomainspacings)atdifferentχ values.Atthelowerχ value,orderedcyclicblockcopolymersareblendedintodisorderedlinearblockcopolymers.Atthehigherχvalue,bothlinearandcyclicareordered.Thelowerχ valueresultsinlowerdomainspacing.Domainspacingsareonlymeasuredfororderedsystems.
BlockCopolymerSelfAssembly
Figure23:Alamellarblockcopolymerwithonepolymertyperemoved
Figure34:Theprocessofblockcopolymernanolithography
0.0
0.5
1.0
1.5
2.0
2.5
0 2 4 6 8 10
g(r)
r
d
Figure5:DomainSpacingsaremeasuredusingradialdistributionfunctions.
Figure6:VisualMolecularDynamics(VMD)isusedtogeneratesnapshotsofthesimulatedpolymers.
AnalysisMethods
PureCyclic
N=8N=12N=16
a)
b)
PureCyclicd0N=16
PureLineard0
PureLinear
Blockcopolymers(BCPs)canbeusedastemplatesfornanolithography.Advancingtechnologydemandssmallerlithographicfeatures.CyclicBCPshavesmallerfeaturesthantheirlinearanaloguesbutaredifficulttosynthesizeinhighpurity.WeuseDPDsimulationtoinvestigatethepotentialofcyclicBCPsasanadditivetoshrinkdomainspacingoflinearBCPs.Wehavefoundastronglinearrelationshipbetweencycliccontentandreduceddomainspacing.Additionally,addinganorderedcyclicBCPcaninduceorderinanotherwisedisorderedlinearBCP.Thisapproachmayallowforfurthershrinkingofdomainspacing,asloweringtheparametersχ andNresultsinsmallerfeaturesbutpotentiallydisorderedsystems.
SCGL
Figure8:BlendsoflinearN=12+cyclicN=24ata=35(lowχ)showatransitionfromdisordertolamellarbetween10%cyclicand25%cyclic.r
dr
References
LinearN=12
CyclicN=24
PureCyclic
![Cyclic nucleotide phosphodiesterase 3B is …cAMP and potentiate glucose-induced insulin secretion in pancreatic islets and β-cells [3]. Cyclic nucleotide phosphodiesterases (PDEs),](https://static.fdocument.org/doc/165x107/5e570df60e6caf17b81f7d2a/cyclic-nucleotide-phosphodiesterase-3b-is-camp-and-potentiate-glucose-induced-insulin.jpg)
