Complex Fluids Design Consortium (CFDC)

www.mrl.ucsb.edu/cfdcOverview and Update

University of California at Santa Barbara

January 23, 2006

CFDC Annual Meeting Agenda –1/23/2006 – Morning Session

9:00-9:30 Welcome and Update (Glenn Fredrickson, Director, CFDC)9:30-10:00 Stiffening effects in nanoparticle reinforced gels and elastomers (Andrei Gusev, ETH)10:00-10:30 Coffee Break10:30-11:00 Progress on a force-bias algorithm in hybrid particle/SCFT simulations (Scott Sides, Tec-X Corp.)11:00-11:30 Field-theoretic simulations at large N (Kirill Katsov, UCSB)11:30-12:00 High resolution methods with SCFT (Eric Cochran, Iowa State U.)12:00-1:00 Lunch

CFDC Annual Meeting Agenda –1/23/06 – Afternoon Session

1:30-2:00 Inhomogeneous polymers with reversible intermolecular bonding(Ed Feng, Miller Inst. UCB, Won bo Lee, UCSB)2:00-2:30 Microdomain defects in 2d block copolymer thin films on flat and curved surfaces (August Bosse, Tanya Chantawansri, and Alexander Hexemer, UCSB)2:30-3:00 Polyelectrolyte brushes in poor solvents: A field theory simulation study (Jonghoon Lee, UCSB)3:00-3:30 Coffee Break3:30-4:00 Beyond the mean field: Efficient implementation of the complex Langevin method (Edward Feng, UCSB)4:00-4:30 Hydrodynamic self-consistent field theory: the continuing saga(David Hall & Sanjoy Banerjee, UCSB, Turab Lookman, LANL)4:30-4:45 Wrap-up, Adjourn CFDC Meeting5:00-6:00 CFDC Steering Committee Meeting (Members Only, Rm 3014 MRL)

CFDC Dinner – 7pm Ming Dynasty—sign up at break

What is the CFDC?The Complex Fluids Design Consortium is an academic-industrial-national laboratory partnership aimed at developing computational tools for:

Designing soft materials, including polymer alloys and complex fluid formulationsAnalyzing the coupled flow, microstructure, and processing behavior of multiphase complex fluids

UCSB Participants

Glenn Fredrickson, Chem. Engr. & Materials (Polymer physics, field theory, mesoscopic simulations)Sanjoy Banerjee, Chem. Engr. & Mechan. Engr. (Turbulence modeling, multiphase flow of structured fluids)Hector Ceniceros, Mathematics (Numerical methods, multiscale PDEs, computational fluid mechanics)Carlos Garcia-Cervera, Mathematics (Numerical methods, stochastic PDEs)Others, as per interest

National Lab ParticipantsLANL

Turab Lookman (kinetics of phase transitions)Tony Redondo (multiscale materials modeling)

SNLJohn Curro (liquid state theory, PRISM)Gary Grest (MD, MC of polymers)Amalie Frischknecht (Density functional theory, PRISM)

Other Academic CollaboratorsAndrei Gusev, Materials, ETH Zurich

Finite element methodsComposite media modeling (Mechanical, transport, and optical properties)

David Morse, Chemical Engineering, U. Minnesota

SCFT theory and algorithms

David Wu, Chemistry and Chemical Engineering Depts., Colorado School of Mines

Molecular simulationsPRISM

Current Industrial Partners

Arkema Chemicals (Full)Mitsubishi Chemical (Sustaining)Rhodia (Sustaining)General Electric CR&D (Full)Dow Chemical (Full)Nestle Research Center (Full)

The Problem—Design of Polymer FormulationsPolymer formulations are complex fluids:

Multiphase plasticsSolution formulationsProcessed foods…Can exhibit complex self-assembly and phase behavior

Relationship between formulation, structure, and properties difficult to establish

Trial and error experimentation is norm

Can Theory/Simulation help?

What do we hope to accomplish?

To create a suite of models, theoretical approaches, numerical methods, and software that:

Can be shared among the members of the consortiumCan be applied to address materials design problems and fluid processing problems of collective or individual interest

Objectives -- continuedCreate a world-class center for complex fluid and soft materials modelingEnhance interactions among the academic, industrial, and national lab partners and pool funding for supporting research projects of mutual interestCreate employment opportunities for the students and post-docs of the consortium

Organization and Partnership Model

UCSB is focal point for the CFDCCFDC “Steering Committee” will guide collective research agendaAcademic partners will contribute:

Time and expertiseAccess to graduate students and postdocsFunding though group grants

National lab partners will contribute:Time and expertiseAccess to computational facilitiesFunding though group grants, and/or DOD/DOE programs

Partnership Model -- continued

Industrial partners will contribute:Staff timeComputational resourcesFunding

As a sustaining memberAs a full member

CFDC Steering Committee 1/06Jun Endou (Mitsubishi)Chris Roger (Arkema)Magali Charlot (Rhodia)Azar Alizadeh (GE)Raffaele Mezzenga (Nestle)Valeriy Ginzburg (Dow)Turab Lookman (LANL)John Curro (SNL)Andrei Gusev (ETH)Sanjoy Banerjee (UCSB)Glenn Fredrickson (UCSB), Chair

Update--Leveraged Activities

Institute for Collaborative Biotechnologies (ICB)

Our grant was renewed for 06-07 to support a post-doc working in extending SCFT to polyelectrolytes

PD – SCFT for Polyelectrolytes (Jonghoon Lee)

IGERT Program of the NSF in Computational Science and Engineering

The UCSB PIs participated in a successful proposal for graduate training that commenced Spring 2003

GS – Time integration methods for stochastic field-based simulations (Erin Lennon)GS—Pseudo-spectral solutions of the wormlike chain Fokker-Planck equation (Tanya Chantawansri)

Leveraged Activities – Ctd.Materials Research Laboratory (NSF MRSEC)

Several of the PIs participate in MRL programs and have access to MRL computational facilities. The MRL was renewed for 2006-2012 at $20.5MThe MRL computing facility is undergoing a major upgrade this year by 128+ processorsA pool of matching funds for unrestricted industrial gifts is available (MRSEC match on first $100K of CFDC gift funds)

Field-Theoretic Computer Simulations

Atomistic simulations of nano-structured polymers are not feasible

Field-theoretic simulations of field-based models provide:

Seamless connection to continuum property modeling Spatial resolution can be continuously adjusted by spectral, FD, or FE field representations Polymeric Microemulsion,

Bates et.al. 1997

≈1014 “atoms” τ>10 s

From Particles to FieldsExample: diblock copolymers

s

rA

rB

A

B

Hubbard-Stratonovich transformation

A

B

Q = single-chain partition function

Mean-Field Approximation: SCFT

• SCFT is derived by a saddle point approximation to the FT:

• The approximation is asymptotic for

• We can simulate the field theory at two levels:

• “Mean-field” approximation (SCFT): F ≈ H[w*]

• Full stochastic sampling of the complex field theory: “Field-theoretic simulations” (FTS)

Glenn’s book is finally out! After two years of planning, writing, proofreading and pain, it is publishedThanks to all of you who made comments, contributed figures, or provided encouragement!

The Equilibrium Theory of Inhomogeneous

Polymers

(Oxford, 2006)

Scientific UpdateParallel SCFT Code – F90 and C++ versions! (Scott Sides & Eric Cochran)Hybrid particle-field simulations of nano-particle/block copolymer composites (Scott Sides, Eric Cochran, Dominik Duechs/GE)SCFT in complex geometries and defect annealing strategies (August Bosse, Scott Sides, Kirill Katsov, Carlos Garcia-Cervera, Hector Ceniceros, Tanya Chantawansri/NSF)Supramolecular polymers (Ed Feng, Won bo Lee, Richard Elliott/Dow)Field-theoretic simulations at large N (Kirill Katsov/NSF & ACS)Coupling SCFT with hydrodynamics (Turab Lookman, David Hall, Sanjoy Banerjee/LANL)Beyond mean-field theory (Erin Lennon, Kirill Katsov, Hector Ceniceros, Carlos Garcia-Cervera/NSF Igert)Semi-flexible polymers (Tanya Chantawansri, Hector Ceniceros, Carlos Garcia-Cervera/NSF Igert)Polyelectrolytes (Jonghoon Lee/ICB & Yuri Popov/Rhodia & MCC)ABC block copolymers (Folusho Oyerokun/Arkema)Cubic phases in food grade polymers (Won bo Lee/Nestle)

High-Resolution SCFT(Eric Cochran)

Our pseudo-spectral methods scale as O(M log M), so we can address problems with M~106-107 spatial basis functions

The gyroid structure at right has 8 unit cells computed with 1923 ~ 7x106 modes

We have corrected the Matsen-Schick calculations to show stability of gyroid (Ia3d) at strong segregation

Block Copolymer/Nanoparticle CompositesJ. Chiu, B. J. Kim, D. Pine, E. J. Kramer

Particles Diblock copolymer

HS

CH3

CH3

CH3

nC H C H2C H2* C H

N

*m

n

Au

PS-thiol, n ~ 13 Poly(styrene-b-2 vinyl pyridine)(PS- PVP), m ≈ n

PS-PVP bulk film

Epoxy Substrate

Film preparation:2 wt% PS-PVP (dichloromethane)Au-PS: 0.1-0.4 wt. frac.Solvent anneal at 25°C

~100 µm

particle area fraction

a. 0.03b. 0.07c. 0.15d. 0.15

100nm 100nm

100nm 100nm

TEM's of symmetric PS-b-P2VPdiblock with PS-coated Aunanoparticles (~5nm) from BJ Kimin Kramer's group at UCSB.

The PS-coated Au nanoparticles are wet by the PS monomers, and are thereforesegregated to the PS (light) domains

lamellar --> HEXphase transition due

to presence of nanoparticles !

Expt. TEM data

A Hybrid Particle-Field Simulation Approach(S. Sides, E. Reister, E. Cochran, D. Duechs)

Combine a field-based description of a polymeric fluid with a particle-based description of the nanoparticlesThe particles are described as cavities in the fluid. The cavities are created by imposing a potential and can:

Be of arbitrary size, shape, and aspect ratioHave a surface treatment to attract or repel any fluid componentHave grafted polymers of any architecture on their surfaces

The fluid field equations are solved even inside the cavities for computational efficiency

particle wet by A(light) monomersarea/particle ~ 0.212 [Rg]2

Note: actual simulation cell copied 3 times in each direction

8 Rg

Hybrid MC/SCFT preliminary results

Rg --> radius of gyration ~(10nm-100nm)

Field theory on the sphereTanya Chantawansri, August Bosse, and Alexander Hexemer have been collaborating on numerical methods for solving SCFT equations in spherical coordinatesThey are using a pseudo-spectral approach based on the SPHEREPACK routines for fast spherical harmonic synthesis and analysisRelevant problems include:

Block copolymer thin films on a curved substrateStructuring of polymer media about a heterogeneous nanoparticle or colloidProblems involving semiflexible polymers—liquid crystals and conjugated polymers

R = 3 R = 4 R = 4.8

An example: Diblock copolymers on a sphere

Heterogeneous Supramolecular Polymers (Ed Feng, Won bo Lee, Richard Elliott)

The vast majority of supramolecular systems to date link chemically similar polymers to create compositionally homogeneous networksMuch greater opportunities for unique property sets should arise from linking dissimilar polymers to create block and graft copolymer systemsIn such systems, macrophasesand microphases can compete, and reaction and phase equilibriaboth play into the self-assembly

tough rigid

transparent

Symmetric Phase DiagramWon bo Lee (zA=zB, NA=NB)

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

0.18

0.20

-0.1 -0.05 0 0.05 0.1 0.15 0.2

h/chiN

1/ch

iN

A/B two phase

Lamella phase

Disordered Phase

Strong Segregation Limit

~T

~(-∆ Eb) /EAB

CFDC Annual Meeting Agenda –1/23/2006 – Morning Session

9:00-9:30 Welcome and Update (Glenn Fredrickson, Director, CFDC)9:30-10:00 Stiffening effects in nanoparticle reinforced gels and elastomers (Andrei Gusev, ETH)10:00-10:30 Coffee Break10:30-11:00 Progress on a force-bias algorithm in hybrid particle/SCFT simulations (Scott Sides, Tec-X Corp.)11:00-11:30 Field-theoretic simulations at large N (Kirill Katsov, UCSB)11:30-12:00 High resolution methods with SCFT (Eric Cochran, Iowa State U.)12:00-1:00 Lunch

CFDC Annual Meeting Agenda –1/23/06 – Afternoon Session

1:30-2:00 Inhomogeneous polymers with reversible intermolecular bonding(Ed Feng, Miller Inst. UCB, Won bo Lee, UCSB)2:00-2:30 Microdomain defects in 2d block copolymer thin films on flat and curved surfaces (August Bosse, Tanya Chantawansri, and Alexander Hexemer, UCSB)2:30-3:00 Polyelectrolyte brushes in poor solvents: A field theory simulation study (Jonghoon Lee, UCSB)3:00-3:30 Coffee Break3:30-4:00 Beyond the mean field: Efficient implementation of the complex Langevin method (Edward Feng, UCSB)4:00-4:30 Hydrodynamic self-consistent field theory: the continuing saga(David Hall & Sanjoy Banerjee, UCSB, Turab Lookman, LANL)4:30-4:45 Wrap-up, Adjourn CFDC Meeting5:00-6:00 CFDC Steering Committee Meeting (Members Only, Rm 3014 MRL)

CFDC Dinner – 7pm Ming Dynasty—sign up at break

Participation Levels

Sustaining Member: $35K/yr as an unrestricted gift

Access to annual workshopAccess to shared software toolsAccess to students & postdocsRepresentation on Steering Committee and participation in group project selection

Participation Levels –Ctd.Full Member: Annual funding as unrestricted gift or research contract sufficient to support one postdoc or graduate student

Access to annual workshopAccess to shared software toolsAccess to students & postdocsRepresentation on Steering Committee and participation in group project selectionIndividually customized project to address sponsor’s R&D needs and interests

Gift Verses Research AgreementResearch Agreement

Formal research contract with IP provisionsUCSB overhead assessed at 47.5% of direct costsProject and milestones can be defined in writing

Unrestricted GiftNo formal research contractNo UCSB overhead Eligible for NSF-MRSEC matching fundsSponsor can participate in definition and execution of project

Gift Research Agreement

Student $50,000 $75,000

Postdoc $75,000 $100,000

CFDC Software Distribution PolicySoftware developed at UCSB under CFDC funding will be made available for distribution to industrial partners at no cost, provided:

Use is for non-commercial research or educational purposesRecipient acknowledges that software is provided “as is”

UCSB IGERT Program in Computational Science and Engineering

PhD programDepartments: Chemical Engineering, Computer Science, Mathematics, Mechanical and Environmental EngineeringResearch: Students will work in interdisciplinary teams. Theses will be jointly supervised.

Complex FluidsComputational Materials ScienceMicroscale Engineering

Two new courses:Atomic-Scale Computer Simulation MethodsPractical High-Performance Computing

Internship partners include: Lawrence Livermore National Laboratory, Los Alamos National Laboratory, Sandia National Laboratories, Chevron/Texaco, Avery-Dennison, Air Products and Chemicals, + CFDC members.Career development workshop, guest speakers and visitors, some travel support

Work in Progress and New Capabilities

Sampling techniques for beyond mean-field theory“Sign” problemImproved numerical methods

Systems with quenched and annealed disorderPolydispersityRandom grafting and couplingSupramolecular polymers/reversible bonding

Polyelectrolytes and PE copolymersColloids, nanoparticles and polymersPolymers with intramolecular structure

LCPs – wormlike chainsFreely jointed, freely rotating, RIS models

Nonequilibrium phenomenaQuasi-static controlled stress or strain simulationsProcessing behavior, coupled flow and mesostructuralevolution